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Platinum-Group Element Mineralization in Nipissing Gabbro
Intrusions and the River Valley Intrusion, Sudbury Region, Ontario
VOLUME I
(Spine title: PGE in Nipissing Gabbro and River Valley Intrusions - Vol I)
(Thesis format: Monograph)
by
Laurence Scott Jobin-Bevans
Graduate Program in Geology Department of Earth Sciences
A thesis submitted in partial fulfillment of the requirements for the degree of
Doctor of Philosophy
Faculty of Graduate Studies The University of Western Ontario
London, Ontario, Canada
© Laurence Scott Jobin-Bevans 2004
ABSTRACT
The ~2.5 Ga River Valley intrusion is one of several Early Proterozoic layered mafic
intrusions that, along with the ~2.2 Ga Nipissing Gabbro suite of intrusions, form the
dominant mafic intrusive bodies within the Huronian Magmatic Belt, in the Sudbury
Region, Ontario. These intrusive suites present excellent exploration targets for PGE-Cu-
Ni sulphide mineralization.
In the River Valley intrusion, the Marginal Series rocks are host to magmatic, low-
sulphide, Cu-PGE-rich mineralization that is associated with heterogeneous fragment-
bearing rocks (Breccia Unit). The Breccia Unit is up to 100 m wide and occurs within a
few metres of the intrusive contact. It is characterized by pyroxenitic fragments hosted
by a gabbroic matrix. The geochemistry of the fragments indicates that they are
xenoliths, entrained in the magmas that now constitute the matrix and PGE-rich sulphide
mineralization. PGE-rich sulphide, which is predominant in the matrix but also occurs in
the fragments, was introduced to the intrusion as suspended droplets in a second-stage
magma.
The Nipissing Gabbro represents the intrusive portion of an eroded Continental
Flood Basalt. Low-sulphide, Cu-PGE-rich mineralization is best represented by
stratabound sulphides that occur in the lowermost orthopyroxene gabbro unit.
Chalcophile element variations through mineralized and poorly differentiated intrusions
indicate in-situ sulphide fractionation from the base upwards, whereas other intrusions
exhibit simultaneous inward-directed sulphide precipitation from the base and top of the
sill.
Evidence for significant crustal contamination of the mantle-derived parental
magmas (high (Th/Nb)N), the high PGE tenor of the sulphides, and the lack of PGE-
depletion in the rock units that overly the Breccia Unit at River Valley, suggests that the
sulphides formed in a deep seated “staging chamber”. Here, primitive mantle-derived
magma assimilated crustal rocks and became crustally contaminated which induced S-
saturation and co-precipitation of PGE-rich sulphides and olivine-orthopyroxene
cumulates. When new primitive magma flowed into the staging chamber it displaced the
initial magma and the early-formed cumulates (fragments) and PGE-rich sulphides were
carried upwards in pregnant magmas and emplaced into the River Valley chamber.
iii
Adiabatic decompression in the ascending magma permitted some of the S in the
sulphide melts to dissolve into the magma; PGE would have also remained in the residual
sulphides leading to an increase in the PGE tenor. Evidence for PGE depletion in rocks
overlying PGE-rich mineralized zones in Nipissing Gabbro suggests that the sulphides
went into solution rather than being entrained as droplets in the ascending magmas.
Keywords: Platinum-group elements, Nipissing Gabbro, Nipissing Diabase, River Valley
Intrusion, East Bull Lake Suite, Contact-type, Marginal Series, Chalcophile element,
Southern Province, Continental Flood Basalt, Staging Chamber, Boninite.
iv
ACKNOWLEDGEMENTS
This research project represents a contribution to ongoing investigations into the
characterization of the Huronian Magmatic Province in Ontario, including research at
Laurentian University and the Ontario Geological Survey. This project benefited in part
from funding through an NSERC grant to Dr. Reid Keays and logistical support and
funding in-kind was provided by the Ontario Geological Survey (Dr. Andy Fyon). I am
especially indebted to Anglo American Platinum Corporation Ltd. (Gordon Chunnett and
Ron Hieber), Goldwright Explorations Inc. (Sudbury), and Pacific North West Capital
Corp. for their contributions to field support and sample analysis, and for the use of their
geological database. The author thanks prospectors J. Rauhala, M. Kosovsky, B. Wright,
M. Turcott, F. Racicot, D. Brunne, J. Morgan, R. Huggins, C. Johnson, T. Loney, M.
Loney, G. Salo, and H. Tracanelli, along with Mustang Minerals Corp. (Ken Lapierre)
and Ursa Major Minerals Inc. (Richard Sutcliffe) for their co-operation in accessing
many of the sulphide occurrences. Invaluable field assistance was rendered by
Christopher Jobin-Bevans, Bill Jobin-Bevans, Teslin d’Canine, Grant Mourre, Chris
Gauld, Trevor Richardson, David Lyon, Cecil Johnson, Richard Rintala, Joerg
Kleinboeck, and Steve Wetherup.
I gratefully acknowledge the support from the Department of Earth Sciences,
Laurentian University and in particular Dr. Richard James, who has been researching
East Bull Lake suite intrusions for nearly 20 years, and Dr. Andy MacDonald and Nicole
Tardif for the use of a petrographic microscope. A special thanks to Dr. Michael Lesher
for his constant encouragement, to Troy Richardson and Merilla Clement at the
Geoscience Laboratories for their cooperation, Dr. Michael Easton for his feedback and
discussion on the topic, and Alliance Pacific Resources Inc. for their patience.
Most importantly, I thank my wife Marnie and my son Christopher for their immense
support, patience and understanding over the past seven years. I also thank my parents
(Bill and Onalee), my brothers (Dean and Sandy), and my in-laws (June and Doug) who
have always been there, offering their support and encouragement. I am also grateful to
Dr. David Peck for suggesting the project area, stimulating my interest in PGE and
introducing me to Dr. Reid Keays; and to Dr. Reid Keays and Dr. Neil MacRae for their
support throughout this process and who’s guidance and input has been invaluable.
v
TABLE OF CONTENTS
CERTIFICATE OF EXAMINATION ii
ABSTRACT iii
ACKNOWLEDGEMENTS v
TABLE OF CONTENTS vi
LIST OF TABLES xii
LIST OF FIGURES xv
LIST OF PHOTOS xxiv
VOLUME I
CHAPTER 1: INTRODUCTION 1
1.1 General Statement of Objectives 1
1.2 Location and Access 6
1.3 Previous Geological Work 7
1.4 Terminology 9
1.4.1 Abbreviations 10
CHAPTER 2: COURSE OF INVESTIGATION 12
2.1 Field Work 12
2.2 Geochemical and Petrographic Analysis 13
2.3 Presentation and Interpretation of Geochemical Data 15
2.3.1 Presentation and Interpretation 15
2.3.2 Element Mobility 18
2.3.3 Archaean Tectonics and Mantle Chemistry 18
2.3.4 Partition Coefficients 19
2.3.5 Mass Balance (R Factor) Calculations 19
CHAPTER 3: REGIONAL GEOLOGY 21
3.1 General Geology 21
3.2 Huronian Supergroup 24
3.2.1 Elliot Lake Group 24
3.2.2 Hough Lake, Quirke Lake and Cobalt Groups 26
vi
3.2.3 Development of the Huronian Supergroup 26
3.2.4 Regional Correlation of the Huronian Supergroup 30
3.3 East Bull Lake Suite and Associated Rocks 32
3.3.1 Emplacement Models and Depth 36
3.3.2 Geochemistry and Magma Composition 39
3.3.3 Sulphide Mineralization 42
3.3.4 Platinum-Group Minerals 43
3.3.5 Sulphide and PGE Formation 44
3.4 Nipissing Gabbro Suite and Associated Rocks 46
3.5 Matachewan and Hearst Dike Swarms 49
3.6 Sudbury Dike Swarm and Grenville Dike Swarm 49
3.7 Sudbury Igneous Complex 50
3.8 Regional Metamorphism and Structure 50
3.8.1 Regional Albitization 51
3.8.2 Murray Fault System 52
CHAPTER 4: NIPISSING GABBRO INTRUSIONS 54
4.1 General Geology and Regional Morphology 54
4.1.1 Local Morphology 54
4.2 General Stratigraphy 58
4.2.1 Lower & Upper Quartz Diabase-Gabbro Units 64
4.2.2 Orthopyroxene Gabbro (Gabbronorite) Unit 66
4.2.3 Gabbro Unit 67
4.2.4 Gabbro-Leucogabbro Unit 71
4.2.5 Vari-Textured Gabbro Unit 71
4.2.6 Granophyric Gabbro Unit 73
4.3 Petrography and Mineralogy 77
4.3.1 Lower & Upper Quartz Diabase-Gabbro Units 78
4.3.2 Orthopyroxene Gabbro (Gabbronorite) Unit 78
4.3.3 Gabbro Unit 82
4.3.4 Gabbro-Leucogabbro Unit 82
4.3.5 Vari-Textured Gabbro Unit 82
vii
4.3.6 Granophyric Gabbro Unit 82
4.4 Mineral Chemistry 83
4.4.1 Olivine 83
4.4.2 Plagioclase 84
4.4.3 Pyroxene 84
4.4.4 Sulphides 85
4.4.5 Platinum-Group Minerals 85
4.5 General Geochemistry 88
4.5.1 Emplacement Model for Nipissing Gabbro 89
4.6 Mineralization 93
CHAPTER 5: CONSIDERED NIPISSING GABBRO INTRUSIONS 98
5.1 Introduction and Overview 98
5.2 General Geochemistry 99
5.2.1 Major Element Variations 106
5.2.2 Trace Element Variations 108
5.2.3 Chalcophile (PGE, Cu, Ni) Element Variations 123
5.2.4 Modelling of Sulphide Compositions 141
5.3 Basswood Lake Intrusion – Traverse 143
5.3.1 Geology and Mineralization 144
5.3.2 Major Element Variations 148
5.3.3 Trace and Rare-Earth Element Variations 150
5.3.4 Chalcophile (PGE, Cu, Ni) Element Variations 154
5.4 Appleby Lake Intrusion – Traverse 158
5.4.1 Geology and Mineralization 158
5.4.2 Major Element Variations 161
5.4.3 Trace and Rare-Earth Element Variations 161
5.4.4 Chalcophile (PGE, Cu, Ni) Element Variations 164
5.5 Charlton Lake Intrusion – Traverse 169
5.5.1 Geology and Mineralization 169
5.5.2 Major Element Variations 172
5.5.3 Trace and Rare-Earth Element Variations 176
viii
5.5.4 Chalcophile (PGE, Cu, Ni) Element Variations 176
5.6 AN3 Occurrence and Traverse 184
5.6.1 Geology and Mineralization 184
5.6.2 Major Element Variations 185
5.6.3 Trace and Rare-Earth Element Variations 189
5.6.4 Chalcophile (PGE, Cu, Ni) Element Variations 192
5.7 Bell Lake Intrusion – Traverse 195
5.7.1 Geology and Mineralization 195
5.7.2 Major Element Variations 200
5.7.3 Trace and Rare-Earth Element Variations 202
5.7.4 Chalcophile (PGE, Cu, Ni) Element Variations 204
5.8 Makada Lake Intrusion – Traverse 210
5.8.1 Geology and Mineralization 210
5.8.2 Major Element Variations 219
5.8.3 Trace and Rare-Earth Element Variations 224
5.8.4 Chalcophile (PGE, Cu, Ni) Element Variations 224
5.9 Makada Lake Intrusion – Drill Hole A1-97 232
5.9.1 Chalcophile (PGE, Cu, Ni) and Trace Element Variations 232
5.10 Kukagami Lake Intrusion – Traverse 239
5.10.1 Geology and Mineralization 239
5.10.2 Major Element Variations 247
5.10.3 Trace and Rare-Earth Element Variations 250
5.10.4 Chalcophile (PGE, Cu, Ni) Element Variations 256
5.11 Manitou Lake Intrusion – Traverse 263
5.11.1 Geology and Mineralization 263
5.11.2 Major Element Variations 266
5.11.3 Trace and Rare-Earth Element Variations 266
5.11.4 Chalcophile (PGE, Cu, Ni) Element Variations 268
5.12 Chiniguchi River Intrusion – Detail 268
5.12.1 Geology and Mineralization 268
5.12.2 Major Element Variations 277
ix
5.12.3 Trace and Rare-Earth Element Variations 280
5.12.4 Chalcophile (PGE, Cu, Ni) Element Variations 284
5.13 Rastall Occurrence – Drill Holes JR99-01 and 06 295
5.13.1 Major Element Variations 295
5.13.2 Chalcophile (PGE, Cu, Ni) Element Variations 304
5.14 Summary 315
VOLUME II
CHAPTER 6: RIVER VALLEY INTRUSION 318
6.1 Introduction 318
6.2 General Geology of the River Valley Intrusion 318
6.2.1 External Contacts 320
6.2.2 Country Rocks 321
6.2.3 Structure, Deformation and Metamorphism 323
6.3 Stratigraphy, Mineral Chemistry and Petrography 324
6.4 General Geochemistry 327
6.5 Marginal Series Stratigraphy, Mineralization and Geochemistry 329
6.5.1 General Geochemistry 340
6.6 Petrology and Geochemistry of Drill Hole RV00-22 342
6.6.1 General Geochemistry 350
6.6.2 Major Element Variations 350
6.6.3 Trace and Rare-Earth Element Variations 356
6.6.4 Chalcophile (PGE, Cu, Ni) Element Variations 365
6.7 Petrology and Geochemistry of the Breccia Unit 385
6.7.1 General Geochemistry 392
6.7.2 Major Element Variations 392
6.7.3 Trace and Rare-Earth Element Variations 393
6.7.4 Chalcophile (PGE, Cu, Ni) Element Variations 410
6.8 Modelling of Sulphide Compositions 421
6.9 Summary 424
CHAPTER 7: DISCUSSION AND PETROGENESIS 429
x
7.1 Summary and Implications 429
7.2 Parental Magmas and Contamination 430
7.3 Pregnant Magmas 436
7.4 Genetic Model 437
7.5 Implications to Mineral Exploration 445
REFERENCES 448
APPENDIX I: Specimen Descriptions, Whole-rock and CIPW Data 473
APPENDIX II: Petrographic Descriptions 538
APPENDIX III: Diamond Drill Hole Data Listing and Drill Core Logs 558
VITA 572
xi
LIST OF TABLES
Table 3-1. Tectono-metamorphic history of the Southern Province. 22
Table 3-2. Summary of geochronology for East Bull Lake intrusive suite 34
Table 3-3. Summary of platinum-group minerals in River Valley intrusion 45
Table 3-4. Summary of geochronology for Nipissing Gabbro intrusions 47
Table 5-1. Summary of sample locations in Nipissing Gabbro intrusions 101
Table 5-2. Summary of geochemical characteristics, Nipissing Gabbro rocks 103
Table 5-3. Summary of CIPW normative calculations, Nipissing gabbro rocks 105
Table 5-4. Summary of rare-earth elements features for Nipissing Gabbro rocks 110
Table 5-5. Summary of average chalcophile metals and ratios for all Nipissing
Gabbro samples 124
Table 5-6. Summary of average chalcophile metals and ratios from 59
unmineralized (<0.05 wt% S) Nipissing Gabbro samples 125
Table 5-7. Summary of average chalcophile metals and ratios from 24
mineralized (>0.05 wt% S) Nipissing Gabbro samples 125
Table 5-8. Summary of whole-rock geochemical characteristics for samples from
the Basswood Lake intrusion 146
Table 5-9. Summary of whole-rock geochemical characteristics for samples from
the Appleby Lake intrusion 160
Table 5-10. Summary of whole-rock geochemical characteristics for samples from
the Charlton Lake intrusion 171
Table 5-11. Summary of whole-rock geochemical characteristics for samples from
the AN3 sample section, Casson Lake 188
Table 5-12. Summary of the highest concentrations of PGE-Au-Cu-Ni from
historical sampling of the Charlton Lake sill 189
Table 5-13. Summary of whole-rock geochemical characteristics for samples from
the Bell Lake intrusion 197
Table 5-14. Summary of whole-rock geochemical characteristics for samples from
the Makada Lake intrusion 213
Table 5-15. Summary of chalcophile element concentrations and ratios for
xii
core samples, drill hole A1-97, Rauhala property 237
Table 5-16. Summary of whole-rock geochemical characteristics for samples from
the Kukagami Lake intrusion 243
Table 5-17. Summary of diamond drill core assay results from the
Washagami Lake occurrence 248
Table 5-18. Summary of whole-rock geochemical characteristics for samples from
the Manitou Lake intrusion 265
Table 5-19. Summary of whole-rock geochemical characteristics for samples from
the Chiniguchi River intrusion 270
Table 5-20. Summary of drill core assay results from the Rastall occurrence
in the Chiniguchi River intrusion 277
Table 5-21. Summary of surface channel sample assay results from the
Rastall occurrence in the Chiniguchi River intrusion 278
Table 5-22. Summary of drill core assay results from the Sargesson Lake
occurrence in the Sargesson Lake intrusion 279
Table 5-23. Summary of drill hole data for the composite drill hole, comprising
drill holes JR99-01 and JR99-06, Rastall occurrence 297
Table 6-1. Average and median values and ratios for whole-rock PGE and base
metal concentrations, Marginal Series rocks, River Valley Intrusion 331
Table 6-2ab. Summary of drill core log for drill hole RV00-22, Dana North
Deposit, River Valley intrusion 343
Table 6-3. Average whole-rock chalcophile element concentrations for core
samples from drill hole RV00-22, River Valley intrusion 344
Table 6-4. Geochemical data from drill hole RV00-22, Dana North Deposit
River Valley intrusion. 351
Table 6-5. CIPW normative calculations for samples from drill hole RV00-22 352
Table 6-6. Principal features of trace and REE abundances and ratios for each
of the units intersected in drill hole RV00-22 357
Table 6-7. Summary of average chalcophile metals and Au, and important metal
ratios for core from drill hole RV00-22 367
Table 6-8. Summary of matrix and fragment samples, River Valley intrusion. 391
xiii
Table 6-9. Summary of whole-rock geochemistry for matrix and fragment
samples, River Valley, intrusion. 394
Table 6-10. CIPW normative calculations for matrix and fragment samples from
the Central and South zones, River Valley intrusion 395
Table 6-11. Principal features of trace and REE abundances and ratios for matrix
and fragment samples from River Valley intrusion 402
Table 6-12. Absolute and average chalcophile abundances and important ratios
for matrix and fragment samples, River Valley intrusion 408
Table 6-13. Chalcophile abundances and ratios for matrix and fragment samples
from the River Valley intrusion 409
xiv
LIST OF FIGURES
Figure 1-1. Regional Geology and location of the study area 2
Figure 1-2. Geology and location of specific intrusions in the study 3
Figure 3-1. Distribution of Early Proterozoic supracrustal rocks in the Great
Lakes Region and correlations with rocks in the study area 23
Figure 3-2. Generalized stratigraphic section through the Huronian Supergroup 22
Figure 3-3. Schematic diagrams showing the successive stages in the palaeotectonic
model for the development of the Huronian Supergroup 28
Figure 3-4. Geological map of the eastern Canadian Shield showing locations of
major anorthosite massifs and the River Valley intrusion 33
Figure 3-5. Correlation between Archaean-Palaeoproterozoic rocks in the study area
and those of the northern Fennoscandian shield, Finland 37
Figure 3-6. Schematic representation of the exposed crustal section in the River
Valley area. east of Sudbury 38
Figure 3-7. Primitive mantle-normalized rare earth element diagrams for samples
from the East Bull Lake suite of intrusions 40
Figure 4-1. Schematic cross-section through a typical undulating Nipissing Gabbro
sill, showing the distribution of lithologies 57
Figure 4-2. Type-section showing the typical sequence of lithologies and features
through a well-differentiated Nipissing Gabbro intrusion 60
Figure 4-3. Model for the evolution of a Nipissing Gabbro sill through the process
of assimilation-fractional crystallization (AFC) 90
Figure 4-4. Model for the development of undulatory Nipissing Gabbro intrusions 91
Figure 4-5. Regional distribution of mineralization in Nipissing Gabbro intrusions
between Lake Temagami and Sault Ste. Marie 95
Figure 5-1. Regional geology in the area east of Sudbury 100
Figure 5-2. AFM diagram for samples from the Nipissing Gabbro rocks 107
Figure 5-3. Variation in Mg-number versus TiO2. 109
Figure 5-4. Primitive mantle-normalized multi-element diagrams for Group-1 data 111
Figure 5-5. Primitive mantle-normalized multi-element diagrams for Group-2 data 112
xv
Figure 5-6. Primitive mantle-normalized multi-element diagrams for chilled
margin gabbro samples 113
Figure 5-7. Mixing curves for primitive mantle-normalized values of (Th/Yb)N
and (Nb/Th)N using 150 unmineralized and mineralized samples 115
Figure 5-8. Chondrite-normalized REE diagrams for Group-1 data 117
Figure 5-9. Chondrite-normalized REE diagrams for Group-2 data 118
Figure 5-10. Chondrite-normalized REE diagrams for chilled gabbro samples 119
Figure 5-11. Plot of Zr/Sm versus Nb/Ta ratios for 50 Nipissing Gabbro rocks 121
Figure 5-12a. Bivariate plots of whole-rock Pd-Pt and Cu-Pd 126
Figure 5-12b. Bivariate plots of whole-rock Cu-Pt and Ni-Pt 127
Figure 5-13a. Bivariate plots of whole-rock S/Se versus Pd 129
Figure 5-13bc. Bivariate plots of whole-rock (La/Sm)N-Pd. and (Th/Nb)N-Pd 130
Figure 5-14. Bivariate scatter diagram of MgO versus Ir 132
Figure 5-15a. Discrimination diagram of Ni/Cu versus Pd/Ir 134
Figure 5-15b. Discrimination diagram of Cu/Ir versus Ni/Pd 135
Figure 5-16. Discrimination diagram of Se versus Pd 137
Figure 5-17a. Primitive mantle-normalized PGE-chalcophile element diagram for
average unmineralized Nipissing Gabbro samples 138
Figure 5-17b. Primitive mantle-normalized PGE-chalcophile element diagram for
chilled margin gabbro 139
Figure 5-18. Primitive mantle-normalized PGE-chalcophile element diagrams for
average mineralized Nipissing Gabbro samples 140
Figure 5-19. Discrimination plot of Pd versus Cu/Pd showing mixing lines between
sulphide and silicate melts at various R factors 142
Figure 5-20. General geology and sample locations, Basswood Lake intrusion 145
Figure 5-21. Schematic diagram of interpreted structure of the Basswood Lake and
Appleby Lake intrusions 147
Figure 5-22. Bivariate scatter plot of Mg-number and wt% TiO2 for samples
from the Basswood Lake intrusion 151
Figure 5-23. Profiles of Mg# and SiO2 through the Basswood Lake intrusion 152
Figure 5-24. Primitive mantle-normalized multi-element diagrams for rock samples
xvi
from the Basswood Lake intrusion 153
Figure 5-25a. Profile of S/Se through the Basswood Lake intrusion 155
Figure 5-25b. Profile of Cu/Ni through the Basswood Lake intrusion 156
Figure 5-26. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from Basswood Lake intrusion 157
Figure 5-27. General geology and sample locations, Appleby Lake intrusion 159
Figure 5-28. Bivariate scatter plot of Mg-number and wt% TiO2 for samples from
the Appleby Lake intrusion 162
Figure 5-29. Profiles of Mg-number and SiO2 through the Appleby Lake intrusion 163
Figure 5-30. Primitive mantle-normalized multi-element diagrams for rock samples
from the Appleby Lake intrusion 165
Figure 5-31a. Profile of S/Se through the Appleby Lake intrusion 166
Figure 5-31b. Profile of Cu/Ni through the Appleby Lake intrusion 167
Figure 5-32. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Appleby Lake intrusion 168
Figure 5-33. General geology and sample locations, Charlton Lake intrusion 170
Figure 5-34. Bivariate scatter plot of Mg-number and wt% TiO2 for samples from the
Charlton Lake intrusion 173
Figure 5-35a. Profile of Mg-number and SiO2 through the Charlton Lake intrusion 174
Figure 5-35b. Profile of TiO2. through the Charlton Lake intrusion 175
Figure 5-36. Profile of Zr and ∑REE through the Charlton Lake intrusion 177
Figure 5-37. Primitive mantle-normalized multi-element diagrams for rock samples
from the Charlton Lake intrusion 178
Figure 5-38a. Profiles of S, S/Se and Cu/Pd through the Charlton Lake intrusion 180
Figure 5-38b. Profiles of Cu/Ni, Pd/Pt, Pt+Pd, Pt/S and Pd/S through the Charlton
Lake intrusion 181
Figure 5-39. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Charlton Lake intrusion 183
Figure 5-40. General geology, locations of sulphide and gold showings, and outlined
location of the AN3 traverse near Casson Lake 186
Figure 5-41. AN3 sample section with general geology and sample locations 187
xvii
Figure 5-42. Primitive mantle-normalized multi-element diagrams for rock samples
from the AN3 sample section 191
Figure 5-43. Profiles of Pt/Se, Pd/Se, Pt, Pd, Cu, Ni, S, S/Se and Cu/Pd through the
AN3 sample section 193
Figure 5-44. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the AN3 section 194
Figure 5-45. General geology and sample locations, Bell Lake intrusion 196
Figure 5-46. Bivariate scatter plot of Mg-number and wt% TiO2 for samples from
the Bell Lake intrusion 201
Figure 5-47. Primitive mantle-normalized multi-element diagrams for rock samples
from the Bell Lake intrusion 203
Figure 5-48a. Profiles of Pt+Pd, Cu, Ni, S/Se, Cu/Pd, S through the Bell Lake
intrusion sample section 205
Figure 5-48b. Profiles of Pd/Se, Pt/Se, Cu/Ni, Pd/Pt through the Bell Lake
intrusion sample section 206
Figure 5-49a. Primitive mantle-normalized PGE-chalcophile element diagrams for
Group-1 andGroup-2 sulphides from the Bell Lake intrusion 208
Figure 5-49b. Primitive mantle-normalized PGE-chalcophile element diagrams for
Group-3 sulphides from the Bell Lake intrusion 209
Figure 5-50. General geology and location of sample area, Makada Lake intrusion 211
Figure 5-51. General geology and locations of samples, Rauhala property 212
Figure 5-52. Schematic diagram showing the interpreted structure of the Makada
Lake intrusion 216
Figure 5-53. Bivariate scatter plot of Mg-number and wt% TiO2 for samples from
the Makada Lake intrusion 221
Figure 5-54a. Profiles of Mg-number and SiO2 through the Makada Lake intrusion 222
Figure 5-54b. Profile of TiO2 through the Makada Lake intrusion 223
Figure 5-55. Primitive mantle-normalized multi-element diagrams for rock samples
from the Makada Lake intrusion 225
Figure 5-56a. Profiles of Pt+Pd, Cu, Ni, S/Se, Cu/Pd, S through the Makada Lake
intrusion sample section 226
xviii
Figure 5-56b. Profiles of Pd/Se, Pt/Se, Cu/Ni, Pd/Pt through the Makada Lake
intrusion sample section 227
Figure 5-57a. Primitive mantle-normalized PGE-chalcophile element diagrams for
Group-1 sulphides from Makada Lake intrusion 229
Figure 5-57b. Primitive mantle-normalized PGE-chalcophile element diagrams for
Group-2 sulphides from Makada Lake intrusion 230
Figure 5-57c. Primitive mantle-normalized PGE-chalcophile element diagrams for
high mineralized samples from Makada Lake intrusion 231
Figure 5-58a. Profiles of Au, Pd, Pt, Se, Ni, Cu and S through drill hole A1-97 from
the Rauhala property (Makada Lake intrusion) 233
Figure 5-58b. Profiles of S/Se through drill hole A1-97 from the Rauhala property 234
Figure 5-59a. Profiles of Co and Cr through drill hole A1-97 from the Rauhala
property (Makada Lake intrusion) 235
Figure 5-59b. Profiles of Pt/Se and Pd/Se through drill hole A1-97 from the Rauhala
property (Makada Lake intrusion) 236
Figure 5-60. General geology and study areas in the Kukagami Lake intrusion 240
Figure 5-61. General geology and location of samples, western portion of the
Kukagami Lake intrusion 241
Figure 5-62. General geology and location of samples, eastern portion of the
Kukagami Lake intrusion 242
Figure 5-63. Bivariate scatter plot of Mg-number and wt% TiO2 for samples from
the Kukagami Lake intrusion 249
Figure 5-64a. Profiles of Mg-number and SiO2 through the Kukagami Lake
intrusion 251
Figure 5-64b. Profiles of TiO2 through the Kukagami Lake intrusion 252
Figure 5-65. Primitive mantle-normalized multi-element diagrams for rock samples
from the Kukagami Lake intrusion 253
Figure 5-66. Primitive mantle-normalized multi-element diagrams for rock samples
from the Kukagami Lake intrusion 255
Figure 5-67a. Profiles of Pd, Pt, Ni, Cu, S/Se, Cu/Pd and S through the Kukagami
Lake intrusion 257
xix
Figure 5-67b. Profiles of Pt/Se, Pd/Se, Cu/Ni, Pd/Pt in Kukagami Lake intrusion 258
Figure 5-68a. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Kukagami Lake intrusion 259
Figure 5-68b. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Kukagami Lake intrusion 260
Figure 5-69a. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from Kukagami Lake intrusion 261
Figure 5-69b. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from Kukagami Lake intrusion 262
Figure 5-70. General geology and location of the sample section for the Manitou
Lake intrusion 264
Figure 5-71. Primitive mantle-normalized multi-element diagrams for rock samples
from the Manitou Lake intrusion 267
Figure 5-72. General geology and location of rock samples from the Chiniguchi
River and Sargesson Lake intrusions 269
Figure 5-73. Schematic map of the Rastall property (Janes Township) showing the
locations of drill holes, trenches and general geology 275
Figure 5-74. Schematic drill hole cross-section from the Rastall occurrence 276
Figure 5-75. Bivariate scatter plot of MgO versus TiO2 for rock samples from the
Chiniguchi River and Sargesson Lake intrusions 282
Figure 5-76. Primitive mantle-normalized multi-element diagrams for rock samples
from the Chiniguchi River and Sargesson Lake intrusions 283
Figure 5-77. Bivariate scatter plots of whole-rock Cu-Pt and Cu-Pd concentrations
from the Chiniguchi River and Sargesson Lake intrusions 285
Figure 5-78a. Discrimination diagram of S/Se versus Pd 286
Figure 5-78b. Discrimination diagram of Se versus Pd 287
Figure 5-79. Discrimination diagram of Ni/Cu versus Pd/Ir 289
Figure 5-80a. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Chiniguchi River & Sargesson Lake intrusions 291
Figure 5-80b. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Chiniguchi River & Sargesson Lake intrusions 292
xx
Figure 5-81a. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Chiniguchi River & Sargesson Lake intrusions 293
Figure 5-81b. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from the Chiniguchi River & Sargesson Lake intrusions 294
Figure 5-82. Bivariate scatter plots of Mg-number and TiO2.and MgO and TiO2
for core samples from the composite drill hole, Rastall occurrence 299
Figure 5-83a. Profile of SiO2 through the composite drill hole, Rastall occurrence 300
Figure 5-83b. Profile of TiO2 through the composite drill hole, Rastall occurrence 301
Figure 5-84a. Profile of Mg# through the composite drill hole, Rastall occurrence 302
Figure 5-84b. Profile of MgO through the composite drill hole, Rastall occurrence 303
Figure 5-85. Bivariate scatter plots Pt-Cu and Pd-Cu for core samples from the
Rastall occurrence 305
Figure 5-86a. Discrimination diagram of S/Se versus Pd 306
Figure 5-86b. Discrimination diagram of Se versus Pd 307
Figure 5-87a. Profiles of Pt/Se, Pd/Se, Pt, Pd, Cu, Ni, S and Cu/Pd through the
composite drill hole, Rastall occurrence 308
Figure 5-87b. Profiles of Cu/Ni, Pd/Pt, Se and S/Se through the composite drill hole,
Rastall occurrence 309
Figure 5-88a. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from core samples, Rastall occurrence 312
Figure 5-88b. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from core samples, Rastall occurrence 313
Figure 5-88c. Primitive mantle-normalized PGE-chalcophile element diagrams for
sulphides from core samples, Rastall occurrence 314
Figure 6-1. General geological map of the River Valley intrusion 319
Figure 6-2. Generalized geology of the northwest portion, River Valley intrusion 328
Figure 6-3. Schematic of typical stratigraphy through the Marginal Series rocks 330
Figure 6-4. Schematic geological section through the Dana South Deposit 335
Figure 6-5. Chondrite-normalized diagram for sulphides in East Bull Lake and
River Valley intrusions 341
Figure 6-6a. Variation in wt% TiO2 in drill hole RV00-22 353
xxi
Figure 6-6b. Variation in wt% MgO in drill hole RV00-22 354
Figure 6-7a. Variation in Zr in drill hole RV00-22 358
Figure 6-7b. Variation in (Th/Nb)N in drill hole RV00-22 359
Figure 6-8. Chondrite-normalized REE plots for average samples from drill hole
RV00-22, Dana North Deposit 362
Figure 6-9. Primitive mantle-normalized multi-element diagrams for samples from
drill hole RV00-22, Dana North Deposit 364
Figure 6-10. Bivariate scatter plots for Cu-Pd and Cu-Pt 368
Figure 6-11. Bivariate scatter plots Pd-Ir and Pd-Pd/Ir 369
Figure 6-12. Discriminant plot of Se versus Pd 371
Figure 6-13. Discriminant plots of whole-rock S/Se versus Pt+Pd 372
Figure 6-14a. Variation in whole-rock S/Se through drill hole RV00-22 373
Figure 6-14b. Variation in whole-rock Pd through drill hole RV00-22 374
Figure 6-15a. Variation in whole-rock Cu through drill hole RV00-22 375
Figure 6-15b. Variation in whole-rock Pd/Pt ratios through drill hole RV00-22 376
Figure 6-16. Variations in the whole-rock Cu/Pd ratio in drill hole RV00-22 379
Figure 6-17ab. Discrimination plots of Ni/Cu versus Pd/Ir and Cu/Ir versus Ni/Pd 381
Figure 6-17c. Bivariate scatter plot of MgO versus Pd/Ir 382
Figure 6-18. Primitive mantle-normalized chalcophile metal abundances for sulphides
in core samples from diamond drill hole RV00-22 384
Figure 6-19ab. Bivariate scatter plots of MgO versus SiO2 and Ir versus MgO 396
Figure 6-19cd. Bivariate scatter plots of MgO versus Al2O3 and Fe2O3 397
Figure 6-19ef. Bivariate scatter plots of MgO vs TiO2 and Al2O3/TiO2 vs V 398
Figure 6-20. Bivariate scatter plots of Zr vs Y and Zr vs (La/Sm)N for fragment and
matrix samples from the River Valley intrusion 399
Figure 6-21. Mixing curves for primitive mantle-normalized values of (Th/Yb)N and
(Nb/Th)N using drill hole RV00-22, fragment, and matrix data 401
Figure 6-22. Chondrite-normalized REE plots for matrix and fragment samples 403
Figure 6-23. Primitive mantle-normalized multi-element diagrams for matrix and
fragment samples from the River Valley intrusion 406
Figure 6-24. Plot of Zr/Sm versus Nb/Ta ratios from whole-rock analyses of 44
xxii
unmineralized and mineralized River Valley intrusion samples 407
Figure 6-25. Discriminant plots of whole-rock S/Se versus Pt+Pd and
concentrations of Pt+Pd recalculated to metals in 100% sulphide 411
Figure 6-26. Discriminant plot of Se versus Pd and Cu/Pt versus Ni/Pd for fragment
and matrix samples from the River Valley intrusion 413
Figure 6-27ab. Primitive mantle-normalized chalcophile metal abundances for
sulphides from the matrix and fragment samples 415
Figure 6-27cd. Primitive mantle-normalized chalcophile metal abundances for
sulphides from the matrix and fragment samples 416
Figure 6-27ef. Primitive mantle-normalized chalcophile metal abundances for
sulphides from the matrix and fragment samples 417
Figure 6-27gh. Primitive mantle-normalized chalcophile metal abundances for
sulphides from the matrix and fragment samples 418
Figure 6-27i. Primitive mantle-normalized chalcophile metal abundances for
sulphides from the matrix and fragment samples 419
Figure 6-28. Discrimination plot of Pd versus Cu/Pd showing the sulphide
compositions of River Valley samples and mixing lines between
sulphide and silicate melt at various R factors 422
Figure 7-1a. Primitive mantle-normalized multi-element diagram comparing
estimates of parental magma compositions for the River Valley
intrusion and Nipissing Gabbro intrusions with heavily
contaminated and uncontaminated Siberian Trap CFB, boninite,
N-MORB and E-MORB 432
Figure 7-1b. Primitive mantle-normalized multi-element diagram comparing
estimates of parental magma compositions for the River Valley
intrusion and Nipissing Gabbro intrusions with heavily
contaminated Siberian Trap CFB 433
Figure 7-2a. Magmatic Model Stage 1 - Staging Chamber 440
Figure 7-2b. Magmatic Model Stage 2 – Displacement 442
Figure 7-2c. Magmatic Model Stage 3 – Ascent 443
Figure 7-2d. Magmatic Model Stage 4 – Emplacement 444
xxiii
LIST OF PHOTOS
Photo 4-1. Kukagami Lake sill “Kukagami Cliff Section”. 56
Photo 4-2.(A) Looking north toward a conformable, sill-like contact and
(B) Irregular contact of Nipissing Gabbro sill 49
Photo 4-3. (A) and (B) Modal and textural layering in Nipissing Gabbro 62
Photo 4-4. Conspicuous textural variations which are possible examples
of textural layering in outcrop at the Rauhala property 63
Photo 4-5. (A) and (B) Gabbro-sediment breccia occurring along the contact
of a Nipissing Gabbro intrusion in Porter Township 65
Photo 4-6. Sulphide-bearing basal breccia in drill core, Rastall occurrence 66
Photo 4-7. (A) and (B) Typical orthopyroxene-gabbro unit 68
Photo 4-8. (A) Typical disseminated and blebby sulphide mineralization and (B)
atypical sulphide textures in orthopyroxene gabbro 69
Photo 4-9. (A) Typical unmineralized, medium-grained orthopyroxene gabbro
and (B) Mafic fragment in medium-grained orthopyroxene gabbro 70
Photo 4-10. (A) typical vari-textured gabbro and (B) coarser-grained gabbro
patches from vari-textured gabbro 72
Photo 4-11. (A) Gabbro pegmatite, termed “snowball” gabbro and(B) close up
of the “snowballs” 74
Photo 4-12. (A) Granophyric pod (or dike?) from the upper portion of the
Basswood Lake Intrusion and (B) Close up of photo (A) 75
Photo 4-13. (A) Miarolitic cavity lined with carbonate and quartz and
(B) patchy sulphide mineralization 76
Photo 4-14. Photomicrographs of Lower & Upper quartz Diabase-Gabbro Units 79
Photo 4-15. Photomicrographs of rocks from the Orthopyroxene Gabbro Unit 80
Photo 4-16. Photomicrographs of altered rocks in the Orthopyroxene
Gabbro (Gabbronorite) Unit 81
Photo 4-17. Photomicrographs of magmatic disseminated and blebby
sulphide mineralization 86
Photo 4-18. BSE images of discrete platinum-group minerals in sulphide-bearing
xxiv
rocks from the Chiniguchi River Intrusion 87
Photo 4-19. (A) and (B) Orthopyroxene gabbro with disseminated and coarse
blebby sulphide from the Bassoon Lake Intrusion 96
Photo 5-1. (A) Aplite dike and (B) Sediment fragment in gabbro from the
Basswood Lake Intrusion 149
Photo 5-2. (A) Medium-grained massive gabbro-orthopyroxene gabbro hosting
distinct “pipe-like” unit of sulphide (PGE) bearing vari-textured gabbro
and (B) Close up of sulphide-bearing vari-textured gabbro; Charlton
Lake Intrusion, Casson Lake AN3 occurrence 190
Photo 5-3. Heavily gossaned Nipissing Gabbro from the northern part of the
traverse across the Bell Lake Intrusion near sample JB98-151 199
Photo 5-4. (A) Fragments of Huronian Supergroup sedimentary rocks in fine- to
medium-grained gabbro and (B) Extensively altered gabbro with
fine-grained blue quartz and finely disseminated sulphide; from the
Makada Lake Intrusion 218
Photo 5-5. (A) Sharp contact between Huronian Supergroup sedimentary rocks
fine-grained gabbro and (B) Medium-grained orthopyroxene gabbro from
the Whalen showing (sample JB98-103A), Kukagami Lake Intrusion 246
Photo 5-6. (A) Fragments of Huronian sedimentary rocks in very-fine-grained to
chilled margin gabbro and (B) Exposed sulphide mineralization at the
Rastall occurrence, Chiniguchi River Intrusion 274
Photo 5-7. (A) Gossan from semi-massive to massive sulphide mineralization
proximal to the intrusive contact and (B) Malachite-stained sulphide
mineralization at the contact, Rastall occurrence 281
Photo 6-1. (A) Tectonized igneous contact along the western margin of the River
Valley intrusion; (B) Chaotic Zone, correlative with the Marginal
and/or Inclusion/Autolith-bearing zones 322
Photo 6-2. (A) Typical footwall (hangingwall) paragneiss to the River Valley
intrusion; (B) Boundary Unit of the River Valley 336
Photo 6-3. (A) Breccia Unit with fragments and mafic matrix; (B) Breccia Unit
with felsic matrix, River Valley intrusion 337
xxv
Photo 6-4. (A) Inclusion-bearing Unit; (B) Fine-grained (diabase) mafic dike
cutting through the Breccia and Inclusion-bearing units 338
Photo 6-5. Layered Units: (A) Modal and textural layering in olivine gabbronorite;
(B) Flat-lying layering in olivine gabbronorite 339
Photo 6-6. Core from drill hole RV00-22. (A) Footwall; (B) Boundary Unit 346
Photo 6-7. Core from drill hole RV00-22. (A) Breccia Unit; (B) Breccia Unit 347
Photo 6-8. Core from drill hole RV00-22. (A) Breccia Unit; (B) Breccia Unit 348
Photo 6-9. Core from drill hole RV00-22. (A) Inclusion-bearing Unit and
(B) Layered Unit 349
Photo 6-10. Central Zone (Dana North Deposit) fragment and matrix sampling from
the Breccia Unit. (A) Fragment sample CZF01, matrix sample CZM01;
(B) Fragment sample CZF02 and matrix sample CZM02 386
Photo 6-11. South Zone (Dana South Deposit) fragment and matrix sampling from
the Breccia Unit. (A) Fragment sample SZF01 and matrix sample
SZM01; (B) Fragment sample SZF05 and matrix sample SZM05 387
Photo 6-12. Fragments in the South Zone (Dana South Deposit). (A) Medium-
grained gabbroic matrix hosting a fine-grained fragment cut by
fine-grained diabase dike; (B) Fragment of layered gabbroic rocks
in massive medium-grained gabbro 388
Photo 6-13. (A) and (B) Photomicrographs typical of the matrix in the Breccia
Unit, Dana South Deposit showing relict igneous textures 389
Photo 6-14. (A) and (B) Photomicrographs typical of extensively altered fragments
in the Breccia Unit, Dana South Deposit 390
xxvi
1
CHAPTER 1: INTRODUCTION
This thesis deals with platinum-group elements (PGE), copper (Cu), nickel (Ni)
sulphide mineralization that occurs in both the Nipissing Gabbro and the East Bull Lake
suite of mafic intrusive rocks within the southeastern portion of the Canadian Shield,
close to the juncture of the Superior, Southern, and Grenville Geological Provinces (Fig.
1-1). These two suites of mafic rocks are the dominant intrusive bodies within the 600
km long Huronian Magmatic Belt as described by Peck et al. (1993a); the Huronian
Magmatic Belt is alternatively known as the Huronian Metallogenic Province.
In approximate chronological order, the Huronian Magmatic Belt includes: basal,
mafic to felsic volcanic rocks of the Elliot Lake Group; north-trending Matachewan dikes
and northwest-trending Hearst dikes (2.45 Ga; Heaman, 1989); East Bull Lake Suite
(James et al., 2002a) intrusions (2.49 Ga; Krogh et al., 1984) that include the East Bull
Lake, Agnew Lake, and River Valley intrusions; the Murray Pluton (2.39 Ga; Krogh et
al., 1984); the Creighton Pluton (2.33 Ga; Frarey et al., 1982); and, Nipissing Gabbro
suite bodies (2.2 Ga; Corfu and Andrews, 1986; Noble and Lightfoot, 1992). The
Nipissing Gabbro and East Bull Lake suites form sills and dikes, from decametres to
kilometres in thickness, at the base of, and within the volcanic-sedimentary rocks of, the
Huronian Supergroup; only Nipissing Gabbro bodies are clearly intrusive into
sedimentary rocks of the Huronian Supergroup. Northwest-trending magnetite-olivine
gabbro dikes (1.24 Ga; Van Schmus, 1975) of the Sudbury Dike Swarm (Shellnutt, 2000)
crosscut all of the older rock types. Anomalous to potentially economic concentrations of
PGE, along with Cu, Ni and gold (Au), occur most commonly in the East Bull Lake and
Nipissing Gabbro suites. Recent increases in demand for platinum (Pt) and palladium
(Pd) as well as improved Pd and Pt commodity prices, have made the Nipissing Gabbro
and East Bull Lake suites attractive Cu-Ni-PGE exploration targets since the mid to late
1980s.
1.1 General Statement of Objectives
This thesis has two main objectives. The first is to characterize PGE-Cu-Ni sulphide
mineralization in a selected number of Nipissing Gabbro intrusions (Figs. 1-1 and 1-2)
through regional and detailed geological mapping, diamond drill core, assays and
petrography.
2
Figure 1-1. Regional Geology and location of the Superior, Southern (Huronian
Supergroup) and Grenville Geological Provinces in north-central Ontario. The principal
study areas (outlined as A and B) include rocks in the (A) Sault Ste. Marie-Elliot Lake
Area, (B) Sudbury-Espanola Area, and (B) Cobalt Embayment (modified after Bennett et
al., 1991). The Basswood Lake and Appleby Lake intrusions are located within area “A”
and details are shown in Figure 5-20. Details of area “B” are in Figure 1-2.
3
Figure 1-2. Geology of the Superior, Southern and Grenville Geological Provinces in the
Sudbury area (Area B from Figure 1-1), and the locations of selected Nipissing Gabbro
intrusions: 1 = Shakespeare Deposit; 2 = O’Brien; 3 = Big Swan; 4 = Brazil Lake; 5 =
Nairn; 6 = Bell Lake; 7 = Charlton Lake; 8 = AN3 Casson Lake; 9 = Bassoon Lake; 10 =
Louie Lake; 11 = Makada Lake; 12 = Ermatinger (Fox Lake); 13 = Moncrieff; 14 =
Rathbun Lake; 15 = Scadding; 16 = Kukagami Lake (Kelly and Carafel Bay); 17 =
Davis-Kelly; 18 = Chiniguchi River (Janes and Sargesson Lake); and, 19 = Manitou
Lake. Also shown are the locations of the East Bull Lake suite intrusions: EBL = East
Bull Lake; M = Massey; A = Agnew (Shakespeare-Dunlop); D = Drury Twp.; W =
Wisner Twp.; F = Falconbridge Twp.; S = Street Twp.; and, RV = River Valley. The
locations of the Basswood Lake and Appleby Lake intrusions are provided in Figure 1-1
and Figure 5-20. Details of the rectangle over the River Valley intrusion are shown in
Figure 6-1.
4
To further that objective, whole rock analyses, including PGE, S and Se concentrations,
will be used to:
1. Determine the ore-forming potential of Nipissing Gabbro magmas, and
in particular the formation of economic accumulations of Cu-Ni-PGE
sulphides;
2. Determine the controls on sulphide mineralization including an
assessment of the S-saturation of the magma prior to the mineralizing
event and evidence for contamination;
3. Identify and assess the effective nature of various elements as
pathfinders in aiding further mineral exploration; and,
4. Determine a petrogenetic history of Nipissing Gabbro and establish the
tectonic environment in which the intrusions were emplaced.
The second objective is to characterize PGE-Cu-Ni sulphide mineralization along the
northern margin (intrusive contact) of the River Valley intrusion (Fig. 1-2) using regional
and detailed geological mapping, diamond drill core, assays and petrography. In
addition, whole rock analyses, including PGE, S and Se concentrations, will be used to:
1. Determine the ore-forming potential of East Bull Lake-type magmas,
and in particular the formation of Cu-Ni-PGE sulphides in the contact
environment;
2. Determine the controls on sulphide mineralization including an
assessment of the S-saturation status of the magmas and evidence for
contamination;
3. Identify and assess the effective nature of various elements as
pathfinders in aiding further mineral exploration; and,
4. Consider the petrogenesis of Cu-Ni-PGE sulphide mineralization in the
River Valley intrusion.
Fundamental to the objectives of this thesis is determining whether or not the
magmas that produced Nipissing Gabbro and the River Valley intrusion were S-saturated
or S-undersaturated at the time of magma formation. If the magmas were S-saturated
5
then they would have been depleted in the ore-forming chalcophile and/or siderophile
elements (i.e. Cu-Ni-PGE) and are not considered capable of producing substantial sized
(i.e. economic) Ni-Cu-PGE deposits (e.g. Keays, 1995). However, if the magmas were
S-undersaturated, then it is expected that the magmas would have kept their full
compliment of chalcophile and/or siderophile elements and would therefore present
excellent PGE exploration targets. When the magmas became S-saturated, whether
through contamination from S-rich sediments, through an increase in silica content in the
magma, or prolonged fractionation of the magma, they would have formed sulphides that
were strongly enriched in Ni, Cu, Au, PGE and other highly chalcophile and/or
siderophile metals. These sulphides would have formed massive magmatic sulphide
deposits and/or disseminated sulphide mineralization; subsequent remobilization of the
sulphides may have also led to the development of hydrothermal Au and/or Cu-PGE
deposits. The most effective way to test the sulphur-saturation model is through
systematic lithogeochemical sampling of both mineralized and non-mineralized rock
units, followed by a geochemical comparison between the two sample suites (cf. Hoatson
and Keays, 1989; Keays, 1995).
The consequences of this research project will be to develop a model that explains
the distribution of the Cu-Ni-PGE metals that is of general use in the exploration for Cu-
Ni-PGE sulphide ores in geological environments that are similar to those of Nipissing
Gabbro intrusions and the River Valley intrusion, and to quantify the physical and
chemical controls on PGE fractionation as they relate to the sulphur fugacity of parent
magmas and the degree of contamination. In addition, the relationship between East Bull
Lake and Nipissing Gabbro suite magmatism will be explored, examining their spatial
and geochemical characteristics, in the context of the geological environment in which
they occur. Specifically, some comparisons will be made to magmatic suites and their
associated mineralization, and supracrustal sequences that occur in the Fennoscandian
Shield in Finland (e.g., Vogel et al., 1998b; Nykänen et al., 1994).
6
1.2 Location and Access
Nipissing Gabbro intrusions were examined within the Sault Ste. Marie-Elliot Lake
area, the Sudbury-Espanola area and the Cobalt Embayment, spanning the region
between Sault Ste. Marie to the west the west shore of Lake Temagami to the east (Fig.
1-1). Access to most of the study areas can be made by provincial highways and the
numerous logging roads and trails that cover the region. Regional sampling was
concentrated in the Southern Province, extending from Wells Township in the west, to
Clement Township in the east and as far south as Curtin Township, near the north shore
of Lake Huron (Figs. 1-1 and 1-2). In addition, a few samples were collected from
Nipissing Gabbro intrusions associated with Huronian Outliers (Rousell et al., 1997),
located within Archaean rocks, near the Benny Greenstone Belt (Moncrieff and
Ermatinger townships). Semi-detailed lithogeochemical sampling, including diamond
drill core sampling, and geological mapping was done at several sulphide occurrences in
Curtin (AN3 Casson Lake occurrence), Janes (Chiniguchi River intrusion), Kelly
(Kukagami Lake intrusion), and Waters (Makada Lake intrusion) townships. Seven
detailed lithogeochemical traverses were completed across 7 Nipissing Gabbro
intrusions: Appleby Lake, Basswood Lake, Charlton Lake, Bell Lake, Makada Lake,
Kukagami Lake and Manitou Lake intrusions (Figs. 1-1 and 1-2). Details on Township
names and locations within the study area can be found on Ontario Geological Survey
Map 2419 (Sault Ste. Marie-Elliot Lake, 1:253,440 scale) and Map 2361 (Sudbury-
Cobalt, 1:253,440 scale).
The River Valley intrusion is located about 100 road kilometres (~60 km direct)
northeast of the City of Greater Sudbury, Ontario (Fig. 1-2). Work by Pacific North West
Capital Corp. and joint venture partner Anglo American Platinum Corporation Limited
(South Africa) has revealed the presence of several potentially commercial base-metal
sulphide associated PGE deposits along the northern contact of the intrusion; an
independent resource study outlined more than 1 million ounces of combined Pd, Pt and
Au (Indicated and Inferred Resources) from three mineralized zones (Pacific North West
Capital Corp. press release 22/07/04). Rock core from drill hole RV00-22, located at the
Dana Lake North deposit (Dana Township), was examined in detail using both
lithogeochemical and petrological methods. In addition, a suite of surface samples
7
comprising fragment and matrix rock material was collected from cleared areas within
the contact environment.
1.3 Previous Geological Work
Much of the early detailed work on the petrology, structure and mineralization in
Nipissing Gabbro and associated metasedimentary and metavolcanic rocks was
concentrated in the Cobalt-Gowganda region (e.g. Bowen, 1910; Collins, 1913;
Hriskevich, 1968; Jambor, 1971; Conrod, 1989). By the 1980s there was increased
interest in Nipissing Gabbro westward toward the Sudbury and Sault Ste. Marie areas,
with particular attention toward their potential as hosts to PGE, and/or Cu, and/or Ni (e.g.
Lightfoot et al., 1986; Rowell and Edgar, 1986; Lightfoot et al., 1987; Lightfoot and
Naldrett, 1989). The present project builds on the early work but will also supplement
more recent contributions (e.g. Lightfoot et al., 1993; Lightfoot and Naldrett, 1996) and
introduce new approaches that will be of use in exploration for Cu-Ni-PGE-rich sulphides
that are both in, and associated with bodies of Nipissing Gabbro.
In the past most mineral exploration associated with Nipissing Gabbro intrusions was
focused in the very rich Co-Ag camp of Cobalt, Ontario where there is a recognized
connection between Nipissing gabbro intrusions and mineralization (e.g. Card and
Pattison, 1973). Sulphide showings in the Sudbury area have been examined and re-
examined for their Cu-Ni potential with the most notable being the Shakespeare Deposit
located in Shakespeare Township, about 65 km west of the City of Greater Sudbury.
First described in 1929 (Moore, 1929), the original sulphide showing has now been
upgraded to deposit status, containing an Indicated Resource of 12.0 million tonnes
grading 0.35% Ni, 0.36% Cu, 0.02% Co, 0.19 g/t Au, 0.34 g/t Pt and 0.38 g/t Pd (Ursa
Major Minerals Incorporated press release 15/04/04). Interest for PGE sulphide
mineralization in Nipissing Gabbro intrusions began in the late 1980’s but it was not until
1998 that it truly began to escalate, intensifying with a rise in the market price of Pd
(+US$1,000/oz) and Pt (+US$600/oz) in early 2001. Since 1998, the author has been
involved in, or has been consulted on numerous exploration projects aimed at PGE-Cu-Ni
sulphide mineralization in Nipissing Gabbro intrusions throughout the Sudbury region,
including but not limited to those outlined in Figure 1-2.
8
The first geological mapping of the River Valley intrusion was completed by
Lumbers (1971 and 1973) as part of regional mapping in the Nipissing and Sudbury
regions. Lumbers interpreted the bulk of the River Valley intrusion to be located in the
Grenville Province and associated it with other Late Proterozoic anorthosite bodies of the
Grenville Province, and stated that it was intruded across the Grenville Front Boundary
Fault (Lumbers, 1978). More recent work has included geological mapping of the River
Valley intrusion at 1:20 000 scale (e.g., Easton and Hrominchuk, 1999, 2001a, 2001b),
regional mapping at 1:50 000 scale (Easton, 2001), and whole-rock, mineral chemistry
and petrographic studies (Easton and Hrominchuk, 2002; Easton, 2003). Ashwal and
Wooden (1989) published a Pb/Pb whole-rock age for the River Valley intrusion of 2562
± 165 Ma and suggested either an enriched mantle source or crustal contamination of a
mantle-derived magma. Easton (2003) reported a precise U/Pb zircon age of 2475 +2/-1
Ma from a sample collected and analyzed by Larry Heaman at the University of Alberta
(James et al., 2002b).
The earliest recorded exploration activity on the northern portion of the River Valley
intrusion (Dana Township) was by Kennco Explorations (Canada) Ltd. in 1968, at which
time they conducted an airborne magnetometer (mag) and electromagnetic (EM) survey
over Janes, Davis, Henry and Dana Townships. In 1969, J.P. Patrie exposed
disseminated and coarse bleb sulphide mineralization in trenches and pits that now
comprise the main showings on the property. In both cases, the main emphasis was on
the exploration for Cu-Ni sulphide deposits and no assays were reported for PGE. In
1973, the Province of Ontario placed more than 110 Townships in a withdrawn area
referred to as the “Temagami Land Caution” – this region was excluded from any type of
resource development until June of 1996. The northern portion of the River Valley
intrusion was covered by this withdrawn area and as a result most of the intrusion was
never explored for its Cu-Ni-PGE potential. Prospecting in August 1998 in the Dana
Lake area by L. Luhta, R. Bailey and R. Orchard resulted in the initial discovery of PGE
mineralization. Pacific North West Capital Corp. and partners Anglo American Platinum
Corporation Limited began exploration programmes on the intrusion in June 1999.
From 1998 to 2004, the author managed or was consulted on numerous Cu-Ni-PGE
exploration programs for public and private exploration companies, which were directed
9
at Nipissing Gabbro and East Bull Lake suite intrusions. During this time, the author was
involved in several important mineral discoveries within these intrusive suites and was
instrumental in organizing the commercial exploration companies in an effort to both
advance their goals and gain more geologic data for this thesis. In addition, the author
worked with the Ontario Geological Survey to advance their geologic database on the
Nipissing Gabbro and East Bull Lake suites.
1.4 Terminology
The term “Nipissing Diabase” was first used by Miller (1911) to represent the
extensive bodies of massive tholeiitic intrusions that occur at Cobalt, the type area.
Intrusions of Nipissing Diabase are not ordinarily diabasic and as such the term
“Nipissing Gabbro” is used here as a more generic term to describe the intrusions; these
two terms are interchangeable.
Primary igneous textures and features have been preserved in the Nipissing Gabbro
suite and River Valley intrusion rocks, mainly as mineral pseudomorphs. Therefore, the
nomenclature of the International Union of Geological Sciences (IUGS) conventions
have been adopted for assigning names and describing fabrics (LeMaitre, 1989).
Descriptions of layering use the definitions and terminology proposed by Irvine (1982).
The majority of rocks that comprise the Nipissing Gabbro suite and River Valley
intrusion are altered and in general the primary mineral assemblage is not well preserved;
the most pristine mineralogy generally survives within the most central parts of the
intrusions. Regional metamorphism caused the replacement of primary pyroxenes (i.e.
orthopyroxene and clinopyroxene) by amphibole, chlorite and epidote group minerals, an
interpretation based on the preservation of relict cumulate textures and relict pyroxene
crystal morphologies. The term “pyroxene” refers to the primary minerals which are
inferred on the basis of textures of amphibole pseudomorphs. Orthopyroxene and
clinopyroxene are not necessarily discriminated and therefore “gabbro” is used as a
general field term for gabbroic rocks and does not refer only to rocks that may have
consisted of an assemblage of clinopyroxene and plagioclase feldspar. In most cases
plagioclase is partially to completely saussuritized and only rarely unaltered. For the
purpose of simplification, the prefix “meta” has not been used in conjunction with
igneous terminology. Unless otherwise stated, the term PGE refers to the total
10
concentration of Pt, Pd and Au and the abbreviation “3E” refers to the total concentration
of Pt, Pd and Au.
All Universal Transverse Mercator (UTM) coordinates are in Zone 17, NAD 83
datum, unless otherwise stated; geographic Longitude/Latitude coordinates are provided
where UTM coordinates are not available.
1.4.1 Abbreviations
For clarification purposes, some of the more common abbreviations used in this
study include:
boninite :an olivine-bronzite andesite that contains little or no feldspar;
generated in modern subduction zone environments within the
upper lithospheric mantle; fluxing of hydrous fluids derived from
an underlying and subducting slab (oceanic plate) serve to lower
the melting temperature and begin to generate magma from
depleted lithospheric mantle.
chalcophile :a group from the geochemical classification of the elements as
defined by Goldschmidt (1937) whereby specific elements (e.g.
Cu, Zn, As, S, Se) are preferentially incorporated into the sulphide
liquid (chalcophilic).
fenitization :ubiquitous alkali metasomatism of quartzo-feldspathic rocks in
the immediate region of carbonatite complexes.
first-stage magma :a magma which is generated from low degrees of partial melting
(i.e. <25%) of the source region (e.g. upper mantle) and is
therefore S-saturated.
Ga :billion years (ago).
lithophile :a group from the geochemical classification of the elements as
defined by Goldschmidt (1937) whereby specific elements (e.g.
Ti, Zr, Hf, Th, La, Ta, Nb, Rb, Sr) are preferentially incorporated
into the silicate liquid (i.e. the crust).
Ma :million years (ago).
11
metasomatism :the process by which a new mineral of partly or wholly different
chemical composition may grow in the space of an old mineral or
old mineral aggregate without little disturbance of the textural or
structural features.
S-saturated :a magma that is saturated with respect to sulphur.
S-undersaturated :a magma that is undersaturated with respect to sulphur.
saussuritization :the process by which calcic plagioclase is altered into a white to
greenish or greyish mineral aggregate consisting of a mixture of
albite, zoisite or epidote, and variable amounts of calcite, sericite,
prehnite and calcium-aluminium silicates; a feature that is
generally indicative of low temperature alteration.
second-stage magma :a magma which is generated from a source region (e.g. depleted
upper mantle) that has undergone a previous episode of low (i.e.
<25%) partial melting and is therefore S-undersaturated.
siderophile :a group from the geochemical classification of the elements as
defined by Goldschmidt (1937) whereby specific elements (e.g.
Fe, Co, Ni, Os, Ir, Re, Ru, Rh, Pd, Pt, Au) are preferentially
incorporated into the iron liquid (i.e. the core-mantle).
tenor :for platinum-group elements and gold, it is used to define the
metal content of the bulk sulphide fraction.
12
CHAPTER 2: COURSE OF INVESTIGATION
2.1 Field Work
The bulk of the regional and detailed sampling was completed from June to
September 1997 and a major part of the 1998 Summer field season was spent conducting
detailed lithogeochemical traverses across several sills of Nipissing Gabbro and
examining sulphide occurrences in areas southwest and northeast of Sudbury (Figs. 1-1
and 1-2). A total of 199 rock samples were collected and submitted for analysis, of
which 188 samples are from seventeen distinct Nipissing Gabbro intrusions (based on
current geological mapping) and eleven are from the hosting Huronian Supergroup
sedimentary rocks; a listing of these samples, with descriptions, geochemical data and
CIPW normative calculations, is provided in Appendix 1.
Eight lithologic sections were completed across seven Nipissing Gabbro bodies:
Appleby Lake, Basswood Lake, Charlton Lake, Casson Lake (AN3 occurrence), Bell
Lake, Makada Lake, Kukagami Lake and Manitou Lake areas (Figs. 1-1 and 1-2).
Detailed geochemical sampling was completed at three sites with historic sulphide
mineralization: the Rauhala property (Makada Lake, Waters Township), Whalen showing
(Kukagami Lake, Kelly Township), and the Jackie Rastall property (Chiniguchi River,
Janes Township). In order to provide an estimate of the regional background chemical
composition for Nipissing Gabbro and their host rocks, samples were collected from
various Nipissing Gabbro bodies in Porter, Moncrieff, Ermatinger, Foster, Nairn, Louise,
Rathbun, Scadding, Janes and Kelly townships (Fig. 1-2). In addition to the lithologic
sample sections and detailed sampling, diamond drill core from the Jackie Rastall
showing in Janes Township (drill holes JR99-01 and JR99-06), and from the Rauhala
occurrence in Waters Township (drill hole A1-97) were reviewed in detail. A total of
sixty-nine drill core samples, twenty-three from Janes and fourty-six from Waters
townships, were collected and submitted for analysis (Appendix 3). Additional site visits
were conducted on other sulphide showings and exploration properties, generally at the
request of the mineral property owners, including the Shakespeare Deposit (Shakespeare
Township), Bassoon Lake showing (Dieppe Township), and O’Brien showing (Dunlop
Township), from 1999 through 2003 (Fig. 1-2).
13
Data collection on the River Valley intrusion began in the Summer of 1999 and
continued into Fall 2003 as part of ongoing exploration programmes by Pacific North
West Capital Corp. and their joint venture partner Anglo American Platinum Corporation
Limited (Fig. 1-2). In 2002, sixteen samples were collected from surface exposures at the
Dana North and Dana South mineral deposits for use in a detailed study comparing and
contrasting the characteristics of matrix and fragment material within the mineralized
breccia unit. Also in 2002, detailed core logging of drill hole RV00-22 was completed
and a total of twenty-eight core and core pulp samples were submitted for whole-rock
geochemical analysis as part of the detailed study through the mineralized breccia unit at
the Dana North deposit. Pacific North West Capital provided assay data (Pt, Pd, Au, Cu,
Ni), drill core log information and core pulp samples from drill hole RV00-22 from
which 112 of the pulp samples were analyzed for Se and S at the Geoscience
Laboratories, Sudbury.
2.2 Geochemical and Petrographic Analysis
The majority of the lithogeochemical samples (229 samples) were submitted for
analysis at the Geoscience Laboratories in Sudbury, Ontario. Representative rock or core
samples, weighing a minimum of 250 g were collected in the field or from drill core by
the author. The majority of rock and drill core samples were crushed using high chrome
steel mills from which approximately 150 ppm Cr and 0.1% Fe contamination may be
expected. Some of the rock samples were prepared by crushing in a steel-plated jaw
crusher and ground in a 99.8% pure Al2O3 planetary ball mill.
At the Geoscience Laboratories, major-elements (SiO2, TiO2, Al2O3, CaO, Fe2O3,
K2O, MgO, MnO, Na2O, P2O5) were determined by Wavelength Dispersive X-Ray
Fluorescence (WD-XRF) on a fused borate disk. Minor- and trace-elements (Be, Co, Cu,
Mo, Ni, Sc, Sr, V, W, Zn) were determined by Inductively Coupled Plasma – Atomic
Emission Spectroscopy (ICP-AES); the commercial laboratories (i.e. ACTLABS and
XRAL - see below) utilized similar determination techniques. Following an acid digest
(perchloric, hydrochloric, hydrofluoric and nitric), Se was determined by hydride Atomic
Absorption Spectrometry (AAS). Total S was determined using standard LECO-infrared
detection methods. These techniques for Se and S were employed at the Geoscience
Laboratories and at the commercial laboratories (see below).
14
The majority of samples (109 samples) were analyzed for rare-earth (Ce, Dy, Er, Eu,
Gd, Hf, Ho, La, Lu, Nd, Pr, Sm, Tb, Th, Tm, U, Yb, Y) and trace-elements (Cs, Nb, Rb,
Sr, Ta, Zr) using inductively coupled plasma-mass spectrometry (ICP-MS) at the
Geoscience Laboratories in Sudbury; some samples (20 samples) from the River Valley
intrusion were analyzed, using the same technique, at XRAL Laboratories. Complete
digestion of Zr is important if the element is to be relied upon in discrimination plots. All
of the Nipissing Gabbro suite rocks and most of the River Valley intrusion rocks were
digested using the open beaker method; only the fragment and matrix samples from the
River Valley intrusion were digested using the closed beaker method. A consequence of
this is that only the fragment and matrix rocks (16 samples) will have sufficient
(complete) digestion of Zr. Therefore, results obtained from open beaker digestion
represent minimum Zr contents; A.J. Crawford (pers. comm. 2004) suggested that Zr data
collected from standard ICP-MS techniques may be one third to one half less than that
collected by XRF methods. It is also important to note that reliable measurement of Ta
concentrations using standard ICP-MS techniques is considered problematic (A.J.
Crawford, pers. comm. 2004) and these data, along with Zr, should therefore be used
with caution. A review of analytical techniques in the determination of Ta, Zr, Nb, and
Hf is provided by Weyer et al. (2002).
The majority of the platinum-group elements (PGE = Ir, Ru, Rh, Pt, Pd) and gold
(Au) analyses were carried out at the low-level PGE facility of the Geoscience
Laboratories, Sudbury, following the principals and procedures of Jackson et al. (1990)
and Richardson and Burnham (2002). Basically, fifteen grams of powdered rock were
mixed with sodium carbonate, sulphur, silica powder and nickel powder. This mixture
was baked at 1050 C for 1.5 hours in a fire-clay crucible (Nickel Sulphide Fire Assay).
After dissolution of the Ni-sulphide button in concentrated hydrochloric acid, the PGE
were collected by tellurium co-precipitation, vacuum filtered, re-dissolved in acid regia
(digestion using hydrochloric and nitric acids) and brought to volume by deionized water.
The PGE concentrations are then determined by ICP-MS. The limits of detection
(average blank plus three standard deviations) are provided in Appendix 1. At the
commercial laboratories (see below) “exploration grade” concentrations for the platinum-
group elements Pt, Pd and Au are determined following standard lead collection-fire
15
assay techniques, utilizing thirty grams of powdered rock sample, with final
concentrations measured using ICP-MS.
Assay and geochemical data, mainly on drill core samples (RV00-22) from the River
Valley and Chiniguchi River intrusions (JR99-01 and JR99-06), was provided through
exploration work by Pacific North West Capital Corp. (Vancouver) and Goldwright
Explorations Inc. (Sudbury). Analyses for these sample suites were performed by
commercial laboratories XRAL Laboratories (Toronto), ACTLABS (Ancaster),
Accurassay Laboratories (Thunder Bay), Chemex Labs (Vancouver), and Bondar-Clegg
(ALS Chemex) Laboratory (Val d’Or). Analytical techniques and lower limits of
detection varied depending on the laboratory and techniques used but all of the
laboratories followed standard analytical procedures. Unless otherwise indicated the
limits of detection are those listed in Appendix 1. A complete listing of the data and
sample descriptions are provided in Appendix 1.
Thin sections, polished and covered (~30µm thickness), were prepared at the
Department of Earth Sciences, Laurentian University using standard procedures. A total
of 140 thin sections were made - 104 from Nipissing Gabbro rocks and thirty-six from
the River Valley intrusion rocks - in order to determine the amount of alteration and
metamorphism within each specimen, and to ascertain the degree of secondary veining
and/or structural fabrics. Petrographic descriptions and modal percentages of constituent
minerals, completed on the 140 thin sections, are summarized in Appendix 2.
2.3 Presentation and Interpretation of Geochemical Data
Whole-rock major element, trace element, rare-earth element and PGE+Au data are
provided in Appendices 1 and 3. The Mg-number, mainly used as a measure of the
degree of magma differentiation, is defined according to Cox (1980) as:
[1] (wt% MgO/mol. wt) / [(wt% MgO / mol. wt) + (0.85)(wt% Fe2O3* / mol. wt)]
Cox (1980) assumed that 15% of the total Fe in the whole rock is oxidized. The whole
rock analysis presented in this study lists the total iron oxide content as Fe2O3*. Total Fe,
reconstituted to FeO(t), is calculated using the formula:
[2] FeO(t) = FeO + (Fe2O3 x 0.89981)
2.3.1 Presentation and Interpretation
16
Various major, trace, rare-earth and chalcophile/siderophile element plots are
presented for each of the data sets, utilizing bivariate scatter plots, ternary diagrams (i.e.
AFM), chemostratigraphic plots, primitive mantle-normalized multi-element diagrams
(also referred to as spidergrams), chondrite-normalized rare-earth element diagrams, and
primitive mantle-normalized chalcophile/siderophile element diagrams (also referred to
as PGE spider plots). A review of the use of various geochemical plots and
discrimination diagrams is provided by Rollinson (1993).
The CIPW normative calculations of the analysed samples were completed using a
spreadsheet based software program written by Kurt Hollocher (Geology Department,
Union College, Schenectady, New York) and following the methods described by
Johannsen (1931). As only Fe2O3 was measured for all of the whole rock analyses,
CIPW normative calculations for iron were completed using a standard ratio of 0.14 to
represent the molar ratio of (Fe3+/total iron). This value was chosen on the basis of Fe2+
and Fe3+ concentrations reported by Easton (2003) from gabbroic rocks in the River
Valley intrusion. Prior to the Contents of S and CO2 were included in the calculations
but LOI was excluded. The chemical analyses were recalculated to 100% prior to
calculating the normative and all results of the CIPW normative calculations are reported
as weight percent normatives.
Primitive mantle-normalized multi-element diagrams or spidergrams, using primitive
mantle values from McDonough and Sun (1995), are used to display the variations in
Large-ion Lithophile Elements (LILE), rare-earth elements (REE) and High Field
Strength Elements (HFSE) from the various rock suites and to ascertain their most likely
tectonic history. Anomalous patterns exhibited by elements such as Nb, Ta, P and Ti are
of particular importance in these plots as negative Nb+Ta, P and Ti anomalies, coupled
with relative enrichment in the LILE (and LREE and HREE), suggest magma formation
within a subduction zone environment and/or mantle metasomatism and/or interaction
with continental crust. A review of crustal contamination signatures as they relate to
incompatible trace elements in spidergrams is provided by Thompson et al. (1984) but the
reader is cautioned that the extent to which geochemical variations are caused by source
heterogeneity versus crustal contamination is a point of controversy. References to
crustal contamination or crustal assimilation, which are made throughout this study, refer
17
not to the wholesale, physical consumption of the crustal material, but rather to small
amounts of partial melting of the crustal material. Seifert et al. (1992) suggested that 1%
partial melting of crustal material could remove large amounts of incompatible elements
without noticeably affecting the major-element composition.
Chondrite-normalized REE diagrams, using chondrite values from Lodders and
Fegley (1998), are used to display the REE and HFSE characteristics of the rock sample
suites (i.e. LREE/HREE and Eu anomalies) and to determine their most likely tectono-
magmatic history. An overview of the use of REE diagrams for Archaean ultramafic and
mafic rocks is provided by Sun and Nesbitt (1978) and by Wyman (1996).
Primitive mantle-normalized chalcophile/siderophile element diagrams, with their
metals re-calculated into 100% sulphide, are used to compare sulphides that underwent
different degrees of fractionation. The chalcophile and siderophile metals (Ni-Ir-Ru-Rh-
Pt-Pd-Au-Cu) are arranged in order (from left to right) of decreasing melting
temperature, resulting in patterns that document the petrogenesis of the sulphide (Barnes
et al., 1988). Sulphide segregation will deplete all PGE evenly, resulting in little
fractionation, but the crystallization of olivine, oxide (i.e. chromite), some high
temperature platinum-group minerals (PGM), and monosulphide solid solution (mss),
which is pyrrhotite-rich, will preferentially incorporate Os, Ir, Ru and Rh (Maier et al.,
1998); the fractionated sulphide phase will tend to be slightly enriched in Ni and strongly
enriched in Cu, Pt, Pd, and Au. The result is a series of profiles showing flat, negative or
positive slopes: flat patterns indicate mantle and primary partial mantle melts; olivine-
oxide cumulates tend toward negative slopes (i.e. ophiolites) with Os-Ir-Ru strongly
enriched relative to mantle; and, positive slopes (Pt-Pd-Au-Cu > Ni-Ir-Ru-Rh) reflect
more fractionated sulphides, commonly associated with evolved layered intrusions. The
usefulness of chalcophile metal ratio diagrams (Barnes et al., 1988) in determining
whether sulphide ores may have undergone mss fractionation and their application to
mineral exploration is reviewed by Maier et al. (1998).
On some of the diagrams, the chalcophile/siderophile metals and gold have been
normalized to 100% sulphides by using the S contents from the samples and assuming
that the average S content of the sulphides in the samples is 36.5 wt% S. This S value is
the S content in pure FeS (i.e. troilite – natural pyrrhotite will be more S-rich) and it is
18
used assuming that pyrrhotite is the dominant sulphide phase and that 100% sulphide
would therefore contain 36.5 wt% S. Several authors (e.g. Iljina, 1994; Keays and
Lightfoot, 2004) have used similar values in their recalculation of chalcophile/siderophile
metals in 100% sulphide. A review of the calculation and use of sulphide metal contents
in magmatic ore deposits is provided by Kerr (2001).
2.3.2 Element Mobility
Rock samples used in this study have undergone some degree of alteration and have
been subjected to a minimum of greenschist facies metamorphism and, as such the effects
of element mobility on the geochemistry of the rocks should be considered. The
problems of metamorphism and alteration in mafic igneous rocks have long been
recognized and the effects of hydrothermal alteration and greenschist facies
metamorphism are variable with respect to different elements (Pearce and Norry, 1979;
Lesher et al., 1991; Wyman, 1996). Although many of the so-called “immobile”
elements are potentially very mobile in hydrothermal systems, elements such as the
HFSE (i.e. Zr, Y, Nb, Ti, Ta, Hf) are considered by various authors to be mostly
immobile (Pearce and Norry, 1979; Campbell et al., 1984; Rollinson, 1993; Wyman,
1996). In contrast, incompatible LILE such as Cs, Rb, Na, K, Ba and Sr are considered
to be mobile under most circumstances. Elements thought to be slightly mobile include
Si, Al, Mg and Fe, however Si is mobile under some circumstances, as are Mg and Fe,
which are particularly mobile with the introduction of hydrothermal fluids and seawater
(Rollinson, 1993).
2.3.3 Archaean Tectonics and Mantle Chemistry
Compositional characteristics of the Archaean and Proterozoic mantle were different
to those of present day mantle, and as such the interpretation of geochemical data from
Proterozoic mafic igneous rocks must be considered in the context of these potential
differences. A discussion of these proposed differences is beyond the scope of this study
but a review is provided by Bleeker (2002). Various authors have shown that the
principles of uniformitarianism extend back into the Archaean and that tectonic processes
operational in the Archaean are thought to be similar to those in operation in the
Phanerozoic (Windley, 1993). In general, the similarity in these processes justifies the
use of most geochemical diagrams and the application of most theories to the study of
19
Proterozoic rocks. However, significant differences are apparent such as the prolific
occurrence of komatiites in the Archaean and their relative scarcity after ~2.5 Ga, and
their rarity in the Phanerozoic record. This suggests that thermal (Condie, 1989; Zindler
and Hart, 1986) and compositional (Francis, 2003) differences existed in the Archaean
mantle and that compositional differences exist between Archaean and Phanerozoic
volcanic rocks which would reflect these mantle differences.
2.3.4 Partition Coefficients
The affinity of any element for any phase can be expressed in terms of its Nernst
partition coefficient into this particular phase; this is commonly referred to as the “D”
value (e.g. Maier et al., 1998). The partition coefficient is of particular importance to
those elements that are strongly chalcophilic, including Ni, Cu, Se, and PGE. The D
value of an element between a sulphide and silicate melt (assuming equilibrium and a
closed system) is defined as (Naldrett,1981):
[3] Dsulphide/silicate = CC/CL
where CC is the concentration of the metal in the sulphide melt and CL is the
concentration of the metal in the silicate melt. Experimental determinations of D values
have shown that the PGE are extremely chalcophilic (e.g. Peach et al., 1990; Peach and
Mathez, 1996) and Keays (1995) provided a review of the various D values which have
been proposed for the PGE. Partition coefficient estimates for Cu, Ni, and the PGE based
on experimental data and empirical observations vary widely (Peach et al., 1990; Peach et
al., 1994; Keays and Lightfoot, 2004). Unless otherwise stated, partition coefficients
used in this study are DPd = 35,000; DIr = 17,000; DCu = 700; DNi = 250; and, DSe = 700.
The PGE metal contents of the sulphides are closely associated with the mass ratio of the
silicate melt to sulphide melt (R factor) during sulphide segregation (see Section 2.3.5).
2.3.5 Mass Balance (R Factor) Calculations
Campbell and Naldrett (1979) introduced the concept that differing PGE
concentrations may be partly explained by variations in the R factors during the process
of sulphide segregation, where R is the mass ratio of the silicate liquid to the sulphide
liquid. High R factors indicate that relatively few sulphide droplets are segregating and
interacting with the silicate liquid, whereas low R factors signify that many sulphide
droplets are segregating and interacting with the silicate liquid. Lower R factors will
20
result in the effective depletion of the PGE metals from the silicate melt but the PGE will
be diluted (low bulk-PGE contents) and relatively less PGE-enriched than the sulphide
melt that segregated under higher R factor conditions; effectively, the apparent D value
has become smaller.
In order to model the initial chalcophile element contents of the magma(s) that
produced the rocks in this study, it is necessary to first apply Rayleigh’s Law:
[4] CSM = CL x F(D-1)
where CSM is the concentration of the metal in the fractionated silicate melt, CL is the
concentration of the metal in the initial silicate melt, F is the fraction of silicate melt
remaining after fractionation, and D is the distribution coefficient of the metal.
In addition, the metal content of the theoretical initial magma prior to sulphide
segregation is required and this is generally estimated by the R factor equation:
[5] CC = (CL x D x (R+1)) / (R + D)
where CC is the metal concentration (in wt%) in the initial sulphide melt, CL is the metal
concentration in the initial silicate melt, D is the Nernst partition coefficient or D value
for the given element, and R is the R factor of Campbell and Naldrett (1979). This
equation may then be rearranged, solving for R:
[6] R = (CL x D)-(CC x D) / (CC- (CL x D))
Campbell and Barnes (1984) demonstrated that equation [5] may be simplified when D is
much greater than R:
[7] CC = CL x (R + 1)
This equation is generally applicable in the case of PGE due to their very high D values.
Graphical methods to determine R factors have also been developed (Barnes et al., 1993)
and these are reviewed by Maier et al. (1998). As signified by Maier et al. (1998) it is
important to note that because the D values for PGE with respect to sulphide are so much
higher than those of Cu and Ni, relatively small amounts of segregating sulphide (high R
factor) do not significantly deplete the silicate melt in Cu and Ni, but small amounts of
sulphide melt do strongly deplete the silicate magma in PGE. A consequence of this is
that PGE are less likely to form a large proportion of the total metals in large, massive
sulphide deposits and that disseminated sulphide deposits tend to produce the highest
PGE concentrations.
21
CHAPTER 3: REGIONAL GEOLOGY
3.1 General Geology
The Superior, Southern, and Grenville Geological Provinces are present within the
southeastern Canadian Shield in the area between Cobalt and Sault Ste. Marie (Figs. 1-1
and 1-2). The Neoarchaean Superior Province consists mainly of east-trending, granite-
greenstone belts and a variety of granitic and gneissic rocks. These rocks form the
basement upon which rocks of the Palaeoproterozoic Southern Province rocks were
deposited (i.e. Huronian Supergroup) and constitute much of the source terrane for the
Palaeoproterozoic metasedimentary and metavolcanic rocks of the Huronian Supergroup
(Bennett et al., 1991; Card and Jackson, 1995). In addition to Huronian Supergroup
volcano-sedimentary rocks, the Southern Province in Ontario comprises rocks of the
Early Proterozoic (~2.49 Ga) East Bull Lake intrusive suite (Easton, 1999; Vogel et al.,
1999), the ~2.2 Ga Nipissing Gabbro suite, the ~1.85 Ga Sudbury Igneous Complex
(Krogh et al., 1987), anorogenic intrusive rocks emplaced between 1.5 and 1.45 Ga
(Easton, 1998) and 1.24 Ga (Van Schmus, 1975) northwest-trending olivine-magnetite
gabbro dikes of the Sudbury Dike Swarm. The Grenville Province terminates against the
Superior and Southern provinces to the north with the Grenville Front Boundary Fault
marking this juncture and defining the northwest limit of intense deformational events
relating to the Meso- to Neoproterozoic Grenville Orogeny. A summary of the
geological history of the Sudbury region is provided in Table 3-1.
In the Lake Superior region of the Southern Province (Wisconsin, Michigan and
Minnesota), the arcuate Mesoproterozoic (1110-1090 Ma; Thurston, 1991) Mid-continent
Rift includes volcanic rocks (Keweenawan flood basalts) of the ~1.1 Ga Keweenawan
Supergroup (Sutcliffe, 1986), sedimentary rocks of the ~2.2 Ga lower and ~1.85 Ga
upper Marquette Range Supergroup, and the ~2.1 Ga to 1.85 Ga Animikie Group (Fig. 3-
1). Upper Cobalt Group rocks of the Huronian Supergroup, representing passive margin
and glacial deposits, are thought to be equivalent to the rocks of the lower Marquette
Range Supergroup (Hoffman, 1989; Young, 1983). Collision of the Wisconsin Magmatic
Terrane (Hoffman, 1989), interpreted as an island arc, with the Superior Province craton
and passive margin deposits of the Southern Province marked the onset of the ~1.85 Ga
Penokean Orogeny (Bennett et al., 1991).
22
Era/Subdivision Time (Ma) Tectonic Event Ref.Neoarchaean >2500 - -
Palaeoproterozoic 2490-2440 plume-induced rifting, south margin Superior ProvinceHuronian sedimentation, volcanism begins (basin-fill) 1
Palaeoproterozoic 2500-1600 - -2500-2200 Development of the Huronian Magmatic Province 22496-2475 East Bull Lake suite intrusions 32489-2443 Matachewan-Hearst dyke swarm 4
2450 Copper Cliff Formation 52400-2200 BLEZARDIAN DEFORMATION 6
2388 Murray Pluton 52333 Creighton Pluton 72200 plume-induced rifting, northeastern Superior Province 8
2210-2069 Nipissing Gabbro suite 31879-1820 EARLY PENOKEAN DEFORMATION 9
1850 Sudbury Event - Sudbury Igneous Complex 51750-1730 Early Killarney Magmatic Belt (anorogenic) 101740-1700 LATE PENOKEAN DEFORMATION 9
1700 Cutler Pluton 11MesoProterozoic 1600-1000 - -
1470-1450 Late Killarney Magmatic Belt (anorogenic) 101.24 Sudbury dyke swarm 12
1100-1070 GRENVILLE OROGENY 10575 Grenville dyke swarm 10
References: (1) Bennett et al. (1991); (2) Peck et al. (1993a); (3) James et al. (2002a); (4) Fahrig (1987);(5) Krogh et al. (1984); (6) Stockwell (1982); (7) Frarey et al. (1982); (8) Ernst et al. (1999)(9) Easton (2000b); (10) Easton (1992); (11) Wetherill et al. (1960); (12) Van Schmus (1975)
Table 3-1. Tectono-metamorphic history of the Southern Geological Province, Sudbury
region.
23
24
3.2 Huronian Supergroup
The Huronian Supergroup is a sequence of sedimentary and volcanic rocks up to 12
km thick and unconformably overlying 2.8-2.5 Ga Archaean granite-greenstone rocks of
the southern Superior Province (Figs. 1-2 and 3-2); a paleoweathering surface is locally
preserved at the unconformity (Bennett et al., 1991). Volcanic rocks of the Elliot Lake
Group (Thessalon, Elsie Mountain, Stobie, Copper Cliff and Salmay Lake) form the base
of the Huronian Supergroup and are spatially associated with intrusions of the East Bull
Lake suite, in the region west of Sudbury (Fig. 3-2). This spatial association is
interpreted to suggest that the East Bull Lake suite intrusions were cogenetic with the
oldest volcanic rocks of the Elliot Lake Group (Card et al., 1977; Card, 1978; Innes,
1977; Tomlinson, 1996). Card et al. (1977) noted Sudbury-type breccia bodies obscure
the nature of the contact between the Drury Township body and the overlying volcanic-
sedimentary sequence (Stobie and Matinenda formations). Elliot Lake Group
sedimentary rocks of the Matinenda and McKim formations, stratigraphically overly the
volcanic rocks.
Immediately overlying the Elliot Lake Group, rocks of the Huronian Supergroup are
subdivided into three major groups on the basis of the cyclical nature of the sediments
(Bennett et al., 1991), viz. (stratigraphically lowest to highest): Hough Lake Group
(Ramsay Lake, Pecors, Mississagi, and Aweres formations), Quirke Lake Group (Bruce,
Espanola, and Serpent formations), and the Cobalt Group (Gowganda, Lorrain, Gordon
Lake, and Bar River formations). The Quirk Lake and Cobalt groups are separated by an
unconformity, and the groups taper to the north where they onlap the Archaean Superior
Province craton (Bennett et al., 1991).
3.2.1 Elliot Lake Group
The Elliot Lake Group consists of both volcanic and sedimentary rocks. The lowest
formation, Livingstone Creek, consists of basal conglomerate and sandstone and is
observed only in the area around Elliot Lake, Thessalon and Sault Ste. Marie, where it is
100 to 400 m thick (Bennett et al., 1991). The Livingstone Creek Formation is overlain
by the Thessalon Formation, which represents an eroded flood basalt province
(Tomlinson et al., 1999) and records volcanism associated with incipient rifting.
25
26
Volcanic rocks of the Thessalon Formation are interpreted by Jolly (1987) to be
metasomatically modified (possibly by Archaean subduction) mafic continental
tholeiites, with a preserved thickness of between 300 and 1200 metres (Bennett et al.,
1991; Jolly, 1987). The Thessalon Formation is divided into a lower series of 4 volcanic
cycles, dominated by basalt to andesite and capped by a unit of rhyolite, and a single
upper series consisting of basalt to basaltic andesite (Tomlinson et al., 1999). On the
basis of whole rock rare-earth element geochemistry, Tomlinson et al. (1999) suggested
that initial volcanism was likely related to adiabatic up-welling due to passive rifting, and
that partial melting was episodic, involving multiple pulses of magma. Tomlinson (1996)
surmised that the principal magma source for the Thessalon volcanic rocks was
metasomatically-enriched upper mantle, which acquired its geochemical signature from
long-lived subduction-accretion events during the Kenoran Orogeny (~2710 to 2660 Ma;
Thurston, 1991). In the Sudbury area, volcanic rocks of the Elsie Mountain, Stobie,
Copper Cliff and Salmay Lake formations generally lie beneath the capping sedimentary
rock sequences but are also observed interfingered with the upper Matinenda and McKim
formations (Bennett et al., 1991). These eastern volcanic belts have a greater thickness
and may be stratigraphically higher than the Thessalon Formation (Bennett et al., 1991).
3.2.2 Hough Lake, Quirke Lake and Cobalt Groups
The Hough Lake, Quirke Lake and Cobalt groups consist of three sedimentary
cycles; a lower conglomerate, middle mudstone to siltstone or carbonate and an upper
quartz-feldspar arenite to quartz-rich sandstone unit (Bennett et al., 1991). Conglomerate
units of the Ramsey Lake, Bruce and Gowganda formations are interpreted as being
glaciogenic in origin, deposited in a marine environment proximal to an ice shelf (Young,
1983; Fralick and Miall, 1989). Siltstone-sandstone units are thought to represent
deposition during intraglacial or post-glacial periods in either fluvial or marine
environments (Young, 1983; Fralick and Miall, 1989).
3.2.3 Development of the Huronian Supergroup
The Huronian Supergroup and igneous rocks of the Huronian Magmatic Belt ( Peck
et al., 1993a) developed as a result of the passive rift-related break up of the Superior
craton (Bennett et al., 1991; Young, 1995; Vogel et al., 1998a). Huronian Supergroup
deposition is interpreted to be the result of a partial Wilson Cycle, involving rifting,
27
represented by the lower Elliot Lake Group, and the development of a southward-facing
passive margin, represented by the upper Huronian groups (Young, 1983; Hoffman,
1989; Bennett et al., 1991); a schematic interpretation of these tectonic events is shown in
Figure 3-3. Incipient rifting events in the development of the Huronian Supergroup, as
represented by the lower Elliot Lake Group, would have pre-dated the earliest period of
volcanism, the lowermost Thessalon Formation, with deposition of basal conglomerates
and sandstones of the Livingstone Creek Formation (Fig. 3-3a). The main-rifting stage
(Fig. 3-3b) would have seen further extension of the rift basin, deposition of lower Elliot
Lake Group volcanic rocks (Thessalon Formation) and contemporaneous intrusion of
East Bull Lake suite mafic rocks. The stage of late-rifting (Fig. 3-3c) would have seen
deposition of sedimentary rocks of the Matinenda and McKim formations which overly
and are intercalated with volcanic rocks of the Thessalon Formation. Subsequent
sedimentary cycles (conglomerate - mudstone, siltstone or carbonate – sandstone) were
deposited during the passive-margin stage (Fig. 3-3d), characterized by the Hough Lake,
Quirke Lake and Cobalt groups. These cycles are thought to represent deposition in
grabens and other depressed features, during episodic continental glaciation along a
passive continental margin (Hoffman, 1989) or further deposition in an epicratonic basin
(Roscoe and Card, 1993). Within each cycle, deposition of glacial till units was followed
by a passive marine sequence represented by shallow–marine and fluvial sands. Intrusion
of the Nipissing Gabbro suite may have began as early as the late-rift or early break-up
stage (Fig. 3-3c). Geochemical features of Nipissing Gabbro, although generally
interpreted to be related to continental flood basalt magmatism (e.g. Lightfoot and
Naldrett, 1996), are also consistent with magmas that have interacted with crustal
material potentially associated with a subduction zone (see Section 5). This suggests that
magmatism associated with the Nipissing Gabbro suite may have occurred during the
period of early continent-island arc collision, spanning events depicted in Figures 3-3d
and 3-3e.
28
Figure 3-3. Schematic diagrams showing the successive stages in the palaeotectonic model for the development of the Huronian Supergroup sedimentary and volcanic rocks, and associated mafic intrusions (East Bull Lake and Nipissing Gabbro suites) in the Southern Geological Province, Ontario. (A) Incipient Passive Rift Stage (extension): Livingstone Creek Formation deposition within early developed grabens. (B) Main Rift Stage: Eruption of Huronian volcanic rocks and emplacement of East Bull Lake suite intrusions during extension. (C) Late Rift-Early Break-up: eruption of volcanic rocks – volcanics rocks found in Sudbury area - and deposition of Matinenda and McKim formations. Early break-up of the craton with possible subsequent formation of the Wyoming Craton (Roscoe and Card, 1993) (Modified after Bennett et al., 1991).
29
Figure 3-3. Schematic diagrams showing the successive stages in the palaeotectonic model for the development of the Huronian Supergroup sedimentary and volcanic rocks, and associated mafic intrusions (East Bull Lake and Nipissing Gabbro suites) in the Southern Geological Province, Ontario. (D) Passive Margin Stage and Initial Closure: deposition of three successive stages of continental glaciation (Cobalt, Quirke Lake and Hough Lake groups) on attenuated continental margin. This stage, which includes the initial closure of the rift basin due to arc-continent collision, likely marks the start of the Nipissing Gabbro suite intrusive event which continues over a period of ~50 Ma and into the beginning of the next stage, marked by intense collision and subduction events. (E) Collision/Subduction Stage: collision of an island arc with the Superior Craton block and deposition of foredeep sedimentary rocks of the Chelmsford Formation. This stage encompasses the metamorphic and orogenic events of the Penokean Orogeny (Modified after Bennett et al., 1991).
30
It is widely accepted that Huronian Supergroup deposition was complete by ~2.2 Ga,
the accepted age of the Nipissing Gabbro suite (Corfu and Andrews 1986; Noble and
Lightfoot, 1992), with termination of the sedimentary cycles brought about by continent-
arc collision between the Superior-Southern geological provinces and the Wisconsin
Magmatic Arc Terrane (e.g. Young, 1983; Hoffman, 1989). The terminal collisional
event, referred to as the Penokean Orogeny (~1.84 Ga; Holm et al., 2001) is understood
to be responsible for most of the metamorphism and deformation present within the
Huronian Supergroup rocks in Ontario and its equivalent rocks in the Lake Superior
region (Wisconsin, Michigan and Minnesota). The scale and intensity of the Penokean
Orogeny in the Sudbury area remains a contentious issue (e.g. Davidson et al., 1992;
Card 1992; Riller et al., 1999) due mainly to the lack of associated plutonism in Ontario.
3.2.4 Regional Correlation of the Huronian Supergroup
Young (1983) suggested stratigraphic relationships between Early Proterozoic
sedimentary-intrusive successions of the Lake Huron (Sudbury-Blind River) and Lake
Superior (Wisconsin and Minnesota) regions, summarizing this relationship in a regional
depositional and tectonic model. Young’s tectono-sedimentary model proposed that in
the Early Proterozoic the region was the site of an aulacogen (intracratonic graben or
trough) that opened into an ocean somewhere to the east-southeast, in the area that is
presently occupied by the Grenville Province. Specifically, Young (1983) considered the
upper part of the Huronian Supergroup (Gowganda, Lorrain and Gordon Lake
Formations) to be correlative with the lower part of the Chocolay Group (Enchantment
Lake Formation, Mesnard Quartzite, and Kona Dolomite-Wewe Slate) of the ~2.2 Ga
Marquette Range Supergroup (Fig. 3-1). Following deposition of the upper part of the
Huronian Supergroup and lower Chocolay Group, the region was subjected to folding,
uplift and intrusion of the Nipissing Gabbro suite (2.206-2.221 Ga; Noble and Lightfoot,
1992) during the McGregor phase. Young relates the intrusion of Nipissing Gabbro with
similarly timed intrusive events south of Lake Superior (Michigan and Wisconsin) and in
Minnesota (Hanson and Malhotra, 1971).
Young (1995) commented on the strong stratigraphic similarities that exist between
sedimentary sequences of the Huronian Supergroup and the Snowy Pass Supergroup
(Wyoming Province). The Cheyenne Belt of southeastern Wyoming is a major east-
31
west-trending shear zone that separates Archaean gneiss and Early Proterozoic
metasedimentary rocks of the Wyoming Province to the north from Proterozoic
eugeoclinal metamorphic rocks to the south (Karlstrom et al., 1983; Karlstrom and
Houston, 1984). Roscoe and Card (1993) proposed that sedimentary rocks of the Early
Proterozoic Snowy Pass Supergroup (Medicine Bow Mountains) and Snowy Pass Group
(Sierra Madre) are equivalent to Huronian Supergroup rocks. In particular, Roscoe
(1990) suggested that there exists a strong positive correlation between all stratigraphic
units of the Phantom Lake strata, Deep Lake Group, and lower parts of the Libby Group
in Wyoming and every unit in the western part of the Huronian Supergroup in Ontario.
Heaman (1997) offers further correlation between the Wyoming and Superior cratons,
noting that dyke rocks in the Bighorn and Beartooth Mountains of Wyoming share many
similarities with Matachewan dykes of the Southern and Superior Provinces.
Tectonic models proposed by Williams et al. (1991), Heaman (1997) and Roscoe and
Card (1993) suggested that the Wyoming Province was welded onto the southern margin
of the Superior Province at about 2.7 Ga. Sedimentary sequences in the Huronian and
Snowy Pass supergroups contain diagnostic horizons in similar stratigraphic positions
that are consistent with deposition in a single, broad, epicratonic basin that developed
atop a large and contiguous Archaean continent comprising the Superior and Wyoming
cratons (Roscoe and Card, 1993). Widespread intrusion of Nipissing Gabbro suite rocks
at ~2.2 Ga and their ~2.1 Ga (Premo and Van Schmus, 1989) equivalents in the
Wyoming Province approximated the onset of continental fragmentation (Fig. 3-3c). The
Wyoming Province fragment split off along the ~1.85 Ga Manitoulin-Niagara structural
zone and was rotated about 135°, as indicated by foresets and other directional features in
preserved sedimentary remnants within the Medicine Bow Mountains and Sierra Madre
(Roscoe, 1990).
The Hurwitz Group occurs as a widespread succession of predominantly
metasedimentary rocks up to 7 km thick in the Hearne Province that have been
interpreted to represent a passive-margin foredeep sequence (Aspler et al., 1989).
Similarities in the stratigraphy of the Hurwitz Group, Huronian Supergroup (Superior
Province) and Snowy Pass Supergroup (Wyoming Province) led Roscoe (1973) and
Young (1973) to propose a regional stratigraphic correlation between the three
32
sedimentary sequences. Patterson and Heaman (1991) supported this interpretation on
the basis of U-Pb baddeleyite-zircon analysis that yielded a minimum age of 2094 +26/-
17 Ma from a gabbro sill within the lower parts of the Hurwitz Group; the age of the
gabbro sill is within error of the ages proposed for Nipissing Gabbro intrusions in the
Southern Province.
Aspler and Chiarenzelli (1997) concur with previous interpretations of the Hurwitz
Group and its possible correlation with rocks of the Huronian and Snowy Pass
supergroups. In addition, these authors expand on the regional model, suggesting that the
rocks of the Huronian and Snowy Pass supergroups, along with several other passive-
margin sequences, were deposited near the boundary of a possible Early Proterozoic
supercontinent – termed Kenorland by Williams et al. (1991) – that may have included
parts of the Superior, Wyoming, Rae-Hearne and Slave provinces. Alternatively,
Patterson and Heaman (1991) conceded that, despite similarities in age and stratigraphy,
the Hurwitz Group may have been deposited on an unrelated microcontinent.
3.3 East Bull Lake Suite and Associated Rocks
East Bull Lake suite intrusions comprise an east-northeast trending, discontinuous
belt in the region of the ~1.85 Ga Sudbury Igneous Complex (Fig. 1-2). The three largest
and most studied are the East Bull Lake (the type example; Born, 1979; Chubb, 1994;
Peck et al., 2001), Agnew Lake (Vogel, 1996) and River Valley intrusions. Most East
Bull Lake suite intrusions were emplaced between 2.491 and 2.475 Ga (Krogh et al.,
1984; Prevec, 1993) and a summary of geochronology on the rocks of the East Bull Lake
suite is provided in Table 3-2. Intrusions of the East Bull Lake suite may represent the
eroded remnants of layered interconnected sills formed from plagioclase-rich tholeiitic
magmas (Vogel et al., 1998a).
The River Valley intrusion is the first of the East Bull Lake suite intrusions to have
certified Measured and Indicated mineral resources (25.4 million tonnes at 0.98 g/t Pd,
0.34 g/t Pt and 0.06 g/t Au; Pacific North West Capital Corp. Press Release, 22/07/04).
Prior to the work of Ashwal and Wooden (1989), the River Valley intrusion was thought
to be part of the belt of Grenville Province anorthosite massifs that extend from the
eastern USA, through Ontario and Quebec and into Labrador (Fig. 3-4). However,
Ashwal and Wooden (1989) reported a Pb-Pb age of 2560 ± 155 Ma and a Sm-Nd age of
33
2377 ± 155 Ma, and surmised that, despite being located within the southwestern
Grenville Province, the River Valley intrusion was best grouped with similar intrusions
west of Sudbury, now considered part of the East Bull Lake suite.
34
Intrusion Age + - Method Ref(Ma) (Ma) (Ma)
Absolute AgesAgnew Lake 2491 5 5 U/Pb zircon 1
East Bull Lake 2480 10 5 U/Pb baddeleyite,zircon 1
2472 76 76 Nd/Sm whole-rock, mineral 21859 5 5 Ar/Ar hornblende 31725 18 18 K/Ar whole-rock 21155 14 14 K/Ar whole-rock 2
Drury Twp. 1855 10 10 U/Pb zircon 4
Falconbridge Twp. 2441 3 3 U/Pb zircon 4River Valley 2475 2 1 U/Pb baddeleyite, zircon 5
2562 165 165 Pb/Pb whole-rock 62377 68 68 Nd/Sm whole-rock, mineral 62165 130 130 Nd/Sm whole-rock, mineral 62185 105 105 Rb/Sr whole-rock 61960 100 100 Rb/Sr whole-rock 6
Street Twp. 2468 5 5 U/Pb zircon 7Relative AgesRiver Valley 2446 3 3 U/Pb baddeleyite, zircon 8, 9
2460 20 20 U/Pb zircon 7, 92475 25 10 U/Pb zircon 7, 9
Street Twp. 2475 25 10 U/Pb zircon 7, 10
References: (1) Krogh et al. (1984); (2) McCrank et al. (1989); (3) Kamineni (1986); (4) Prevec (1993); (5) Easton et al. (1999); (6) Ashwal and Wooden (1989); (7) Corfu and Easton (2001); (8) Heaman (1997); (9) Easton and Hrominchuk (1999)(10) Easton and Murphy (2002)
Table 3-2. Summary of geochronology on rocks from the East Bull Lake suite of
intrusions (after Easton, 2003). Locations of East Bull Lake suite intrusions are shown in
Figure 1-2.
35
East Bull Lake suite intrusions are thought to have been emplaced into Neoarchaean
rocks at moderate to shallow crustal levels (Peck et al., 1993a; Vogel et al., 1999). East
Bull Lake suite intrusions west of the Sudbury Igneous Complex occur at or near the
Southern-Superior boundary but contact relationships between the intrusions and
surrounding Huronian sedimentary rocks are faulted or sheared and so the original
relationship between them is indefinite (Fig. 3-2). East Bull Lake suite intrusions east of
the Sudbury Igneous Complex, and in particular the River Valley intrusion, were likely
intrusive wholly into Neoarchaean rocks which are now located within the Grenville
Front Tectonic Zone (Fig. 1-2).
East Bull Lake suite intrusions, along with mafic and felsic (bimodal) volcanic rocks
of the Elliot Lake Group (Huronian Supergroup), related felsic plutons such as the
Murray and Creighton granites, and the Matachewan-Hearst Dike Swarm, outline the
trace of a plume-induced, regional, Palaeoproterozoic rifting event that lasted from 2.49
to 2.44 Ga, apparently centred in the area of Sudbury (e.g. James et al., 2002b). James et
al. (2002a) and Easton et al. (2004) presented a summary of the suite of igneous rocks,
referred to as the “rifting suite”, that record the initial trace of this intracontinental rifting
event. From oldest to youngest, they include:
~2490 to 2470 Ma: East Bull Lake intrusive suite
~2490 to 2450 Ma: Elliot Lake Group metavolcanic and minor plutonic rocks
- lowermost stratigraphy in the Huronian Supergroup
2473 and 2446 Ma: Matachewan and Hearst mafic dike swarms, respectively
~2450 to 2460 Ma: Elliot Lake Group/Superior Province granitic intrusions
- Creighton and Murray plutons
This rifting event produced a northeast-trending, southward-deepening basin that
probably resulted in the formation of as not yet identified oceanic crust (e.g. Card et al.
1972; Young 1983; Fahrig 1987; Hoffman 1989; Bennett et al., 1991). The geometry of
the northwest-trending dikes of the regionally extensive Hearst-Matachewan Dike swarm
coupled with their distribution with respect to the Elliot Lake Group rocks are consistent
with a north-northwest oriented arm of a failed rift (e.g. Fahrig 1987; Ernst and Buchan
2001). However, it is presently uncertain as to whether the East Bull Lake suite rocks
occur directly along a cryptic structure, or structures, related to this rift basin, or if the
36
present distribution of the bodies reflects some other emplacement mechanism (James et
al., 2002a). Alapieti et al. (1990), Alapieti and Lahtinen (2002), and Vogel et al. (1998b)
have described correlations with similar suites of Palaeoproterozoic intrusions
(Fennoscandian Layered Intrusive Suite) in the northeastern part of the Fennoscandian
Shield (Finland) that were emplaced in similar tectonic environments (Fig. 3-5); Heaman
(1997) suggested that the two regions may have been part of a more extensive ~2.47 Ga
Large Igneous Province (continental flood basalt magmatism).
3.3.1 Emplacement Models and Depth
Previous research on East Bull Lake suite intrusions in the Southern Province
suggested shallow depths (<8 km) of emplacement, possibly at the contact between the
Archaean basement (Superior Province) and supracrustal rocks of the Huronian
Supergroup (e.g. Card 1978; Peck et al. 1995; Vogel et al. 1998a, 1999). However,
Easton (2000a) suggested that the River Valley intrusion was emplaced at deeper levels
(8-12 km), either at the boundary between Archaean plutonic rocks and greenstone belts
or at the boundary between gneisses and a plutonic rock dominated mid-crustal layer.
Easton (2002) further suggested that several depths of emplacement are recorded within
the East Bull Lake suite east of Sudbury (Street, Loughrin, Henry and River Valley
intrusions), with these bodies possessing subtly different features depending on which
country rock gneiss association they are in contact (Fig. 3-6).
James et al. (2002b) reviewed two proposed models to explain the emplacement
mechanism for the East Bull Lake suite. The first model (Vogel et al., 1999), based on a
geological reconstruction and “unfolding” of the effects of Penokean deformation on the
East Bull Lake and Agnew Lake intrusions, proposes that these two intrusions were part
of an extensive, subhorizontal lopolithic sheet, as much as 2 km thick, 30-50 km north-
south, and more than 100 km east-west. James et al. (2002a) expanded this model to
include all of the East Bull Lake suite intrusions, suggesting that these bodies are
remnants of a larger interconnected intrusive body, analogous to the Great Dyke
(Zimbabwe), that would have been traceable for at least 300 km. An important outcome
of this model is that sulphide mineralization could be dispersed in large volumes of rock
(i.e. disseminated, low sulphide mineralization), resulting in relatively low grade PGE-
Cu-Ni sulphide that present excellent bulk tonnage exploration targets.
37
38
39
In addition, this model allows for the lower stratigraphic sequences and associated
mineralization to occupy rift, fault-related structures or embayments that would have
controlled magma intrusion and replenishment, potentially concentrating base metals as
massive sulphide (Cu-Ni) deposits. These lower sequences and associated mineralization
would not be as extensive or as well connected as the upper portions or main mass of the
intrusion, suggesting that deeper sections of these intrusions are promising in terms of
massive sulphide exploration targets.
In the second model, James et al. (2002a) proposed that intrusions of the East Bull
Lake suite were emplaced as groups of smaller, separate bodies, rather than as one or
possibly two large (now dismembered) intrusive complexes. This model implies that
individual intrusions could have been emplaced at different crustal levels, providing an
explanation for the differences in stratigraphy between the various intrusions as observed
by Easton (2000; 2002). An important consequence of this model is that it allows for
much greater variation in mineralization style and grade between intrusions (Easton et al.,
2004).
3.3.2 Geochemistry and Magma Composition
Although previously described as anorthositic intrusions (e.g. Lumbers, 1971, 1973;
Ashwal and Wooden, 1989), exposures and mapping of the East Bull Lake suite have
shown that they are dominated by leucogabbronorite, gabbronorite and smaller amounts
of gabbro, with anorthosite forming a small proportion of the rocks. Melagabbronorite,
troctolite and melatroctolite also occur in the discrete parts of the stratigraphy. Peck et al.
(2001), Vogel et al. (1999) and James et al. (2002a) demonstrated that plagioclase,
olivine, and orthopyroxene fractionation are responsible for the main chemical variation
of the rocks in the East Bull Lake and Agnew Lake intrusions, with very little
contribution from clinopyroxene. Primitive mantle-normalized rare-earth element (REE)
diagrams from the East Bull Lake suite of intrusions show light rare-earth element
(LREE) enrichment (La/Gd ~3-5), whereas the heavy rare-earth element (HREE) patterns
are nearly flat (Fig. 3-7). Weak to strong, positive Eu anomalies dominate except for the
most fractionated rocks in the Agnew Lake intrusion and local “contaminated” rocks in
the Marginal Zone of the River Valley intrusion.
40
41
Rocks lowest in the stratigraphy of each intrusion have the lowest REE contents
consistent with the petrographic and major element interpretations of the stratigraphy of
the intrusions (James and Born, 1985; Vogel et al, 1999; James et al., 2002b).
East Bull Lake intrusion pyroxenites that occur as inclusions have distinctive
patterns compared to those that occur as poorly formed layers; the pattern of the latter
suggests there may be quite primitive mafic liquids in the magma system very early in its
formation, where mineralization is dominant (James et al., 2002b). The LREE
enrichment patterns could be indicative of crustal contamination of a primitive, mantle-
derived magma that intruded the lower crust or alternatively, the LREE-enrichment might
be due to direct partial melting of an initially enriched, metasomatised mantle source
(Vogel et al., 1998a); the latter scenario is consistent with a plume-generated continental
rift event (James et al., 2002b).
Much of the work aimed at determining the magma composition of the East Bull
Lake suite magma(s) has been based on work in the East Bull Lake and Agnew Lake
intrusions (Peck et al., 1995, 2001; Vogel et al., 1998a, 1999; James et al., 2002a) and
very little work has been done to constrain the magmatic evolution of the River Valley
intrusion; estimates of parental magma compositions are reviewed in the context of the
River Valley intrusion by James et al. (2002b) and Easton et al. (2004). These studies
have demonstrated that the magma(s) that formed the East Bull Lake and Agnew Lake
intrusions were high-Al (16-20 wt% Al2O3), except for mela-cumulates, low-Ti (≤0.5
wt% TiO2) tholeiites, with 100-500 ppm S in unmineralized samples, low Cr2O3 (<250
ppm), Mg-number of 54-60, and Cu/Ni = 0.3-0.8 (James et al., 2002b).
In both the East Bull Lake and Agnew Lake intrusions, there is an abundance of
mafic dykes of the Matachewan Dyke Swarm, which are normally plagioclase-phyric
(Osmani, 1991). Vogel et al. (1999) showed that the oldest of these at the Agnew Lake
intrusion, the Streich Dike, has a composition whose major, trace and REE geochemistry
is suitable as a parent for most rock types in the Agnew Lake intrusion. The Streich Dike
intrudes only the lower part of the Marginal Zone and appears to be a major feeder to the
Agnew Lake intrusion (James et al., 2002b). Peck et al. (1993a, 1995, 2001) also
suggested that the Matachewan Swarm dikes are the most likely candidate for parent
magmas to the East Bull Lake suite intrusions. In contrast to East Bull Lake and Agnew
42
Lake intrusions, mafic dikes are not as abundant within or marginal to the River Valley
intrusion (James et al., 2002b). A sample, from a large area of massive norite in Crerar
Township, interpreted as a potential intrusive feeder dike, has an Mg-number of 73 and a
composition of 13.5 wt% Al2O3, 11.5 wt% MgO and 51.5 wt% SiO2, suggestive of a
boninitic composition (James et al., 2002b).
3.3.3 Sulphide Mineralization
James et al. (2002a) presented a summary of general characteristics common to all of
the East Bull Lake suite intrusions studied to date. One feature, significant to mineral
exploration and economic potential of these intrusions, is the presence of PGE-Cu-Ni
sulphide mineralized fragment-bearing lithologies at or proximal to the footwall or
sidewall contacts or margins of these intrusions, referred to as “contact-type” PGE (Peck
et al., 1993a). These fragment-bearing units range in character from igneous breccias that
are strongly heterolithic and have highly variable fragment size ranges, to inclusion-
bearing units that are moderately heterolithic and have much less variable fragment sizes.
The thickness and length (strike-continuity) of these fragment-bearing zones is variable
but the potential for these targets to contain large tonnages of PGE-Cu-Ni mineralization
makes them attractive exploration targets. Mineralization in the three largest East Bull
Lake suite intrusions is best developed where there is a primary igneous contact with rock
units that represent the lowest or outermost (Marginal Zone or Marginal Series)
stratigraphic zone in the intrusion (James et al., 2002b). Vogel et al. (1999) demonstrated
that mineralized zones of “inclusion-bearing gabbronorite” also occur higher in the
stratigraphy at the Agnew Lake intrusion, and that strataform, reef-like mineralization
can occur in the uppermost part of the intrusion. Vogel et al. (1999) attributed the reef-
like mineralization to late, fractionation-induced, sulphide liquation. Contact-type
mineralized zones normally have <1% Cu+Ni, Cu/Ni = 2-20, and PGE = 0.5-4 g/t over 2-
10 m in drill core, with much narrower intervals as high as 8-16 g/t Pt+Pd (James et al.,
2002b).
Sulphide mineralization in East Bull Lake suite intrusions is commonly hosted in
xenolith-bearing units that typically consists of 1-5% chalcopyrite +/- pyrrhotite,
pentlandite, and minor pyrite intergrown with secondary silicate minerals (epidote, calcic
amphibole, chlorite, quartz, ±biotite). Sulphides textures are primarily disseminated and
43
blebby with minor interstitial and subordinate net-textures. The sulphides occur within
relatively massive, medium- to coarse-grained, and typically vari-textured,
leucogabbronorites and gabbronorites, and in the matrix and mafic cognate xenoliths of
inclusion-rich leucogabbronorites and gabbronorites. Typically, sulphide mineralization
is erratically distributed in the massive rocks, and is so fine-grained and in such small
volume (1-5%) as to exhibit little or no gossan. Detailed reviews of PGE-Cu-Ni
mineralization in the East Bull Lake suite intrusions are provided by Peck et al. (1993a,
1995, 2001), Vogel et al. (1999), Cabri (2001) and James et al. (2002a, 2002b).
3.3.4 Platinum-Group Minerals
Cabri (2001) described the platinum-group minerals (PGM), gold and sulpharsenide
minerals in heavy mineral concentrates (pyrrhotite, chalcopyrite, pentlandite, pyrite and
ilmenite) from the East Bull Lake intrusion, using SEM and semi-quantitative EDS
analysis. Cabri (2001) reported that the PGM consist of six palladium minerals: froodite
(PdBi2), kotulskite (PdTe), merenskyite (PdTe2), michenerite (PdBiTe), and other
unidentified Pd-As and Pd-As-Sb phases; two platinum minerals (sperrylite (PtAs2) and
platarsite (PtAsS); and, a rhodium-arsenide sulphide mineral (hollingsworthite (RhAsS).
The sulpharsenide minerals cobaltite and arsenopyrite contain trace to several weight
percent Pd and Rh. The PGM range in size from <1 µm to 22x32 µm, and occur in all
major sulphide minerals although pyrrhotite is the most common sulphide host. Cabri
(2001) also noted that samples containing the highest concentrations of pyrrhotite and
chalcopyrite had higher PGM contents and PGE concentrations. In studying polished
thin sections, Peck et al. (1993a) noted similar PGM for mineralized samples from
contact-type mineralization in the East Bull Lake intrusion; Peck et al. (1993a) also noted
that much of the PGM were at sulphide-silicate grain boundaries, within secondary
silicates, and were commonly within fractures. Similar sulphide-PGM assemblages from
the Portimo Complex (contact-type mineralization) were described by Iljina (1994).
At the Dana North area in the River Valley intrusion, PGM occur as discrete mineral
phases adjacent to base-metal sulphides, enclosed by base-metal sulphides, enclosed by
silicates, and adjacent to silicates (James et al., 2002b). James (2004) reported on PGM
in 12 polished thin section samples from the River Valley intrusion, using SEM and
semi-quantitative EDS analysis. The study described several discrete PGM phases from
44
the Dana Lake, Lismer’s Ridge, Azen and Razor areas and these are summarized in Table
3-3. PGM range from ~3-30 µm but most are within the range 10-20 µm, and are
dominated by Pd-Bi tellurides, Pd-Sb arsenides, and Pt-arsenides with subordinate Pt-
tellurides, Pd-alloys, Pt-Fe-alloys, Pt-Pd-sulpharsenides, and Pt and Pd-sulphides (James,
2004).
3.3.5 Sulphide and PGE Formation
The requirements for the formation of the sulphide-related PGE mineralization
include a fertile magma, an immiscible sulphide liquid, a sufficiently high R-factor
(silicate to sulphide mass ratio; Lesher and Burnham, 1999) related in part to a turbulent,
convecting magma, and sulphide contamination from an external source (Keays, 1995).
For magmas that may be feeders to these intrusions, Pd and Pt concentrations average
18.9 ppb Pd and 24.20 ppb Pt for the Streich Dike (Vogel et al., 1999) and 72 ppb Pd and
38 ppb Pt for Hearst-Matachewan Swarm dikes (James et al., 2002a). These fertile PGE
compositions are typical of second-stage magmas as described by Hamlyn et al. (1985),
Hamlyn and Keays (1986) and Keays (1995). The potential parent magmas (i.e.
Matachewan Dike Swarm), as well as most rocks in the East Bull Lake suite intrusions
are S-undersaturated (~50-500 ppm S) and therefore, to reach S saturation (~800-1000
ppm S), require contamination and/or significant cooling (James et al., 2002b). In the
mineralized Marginal and Inclusion/Autolith-Bearing zones of the River Valley intrusion,
minor local contamination is indicated by rare footwall xenoliths, and chilled diabase in
the Marginal Zone is evidence of relatively rapid heat loss to the footwall (James et al.,
2002b).
Peck et al. (2001), in modelling the magmas of the East Bull Lake intrusion,
determined that there is insufficient PGE in a single large basal magma pulse or pulses to
form the zones of PGE observed in that intrusion. Instead, Peck et al. (2001) suggested
that the contact region of the intrusion was subjected to multiple injections of S-saturated
magma, that transported 1-5% immiscible sulphide droplets which were capable of
scavenging the PGE in a turbulent environment, for significant periods, prior to
emplacement into the contact region of the intrusion.
45
Area PGM Size (µm) Probable PGM IdentityDana Lake Pt-alloy 1-3 -
Pd-Bi-Te 30 x 10; 5-10 micheneritePtAs 5-10 sperrylite
PdAsSb 5-10 palladium antiminideLismer’s Ridge PtAs 5-20 sperrylite
PdSe 5 palladesitePdAs 1-10 palladoarsenide
RhPtAsS 1-10 hollingsworthitePdTe 1-10 merenskyite
PdAsSb vein-like cluster palladium antiminideAzen Creek Pt-Te±Bi,Fe 2-6 moncheite
Pd-S 3 x 3 vysotskiteRazor Pd-Bi-Te 20 x 20; 15 x 8 michenerite
Table 3-3. Summary of platinum-group minerals noted from the River Valley intrusion
(from James, 2004).
46
3.4 Nipissing Gabbro Suite and Associated Rocks
More than 25% of the areas of the southern Superior and Southern geological
provinces in Ontario are covered by the dominantly gabbroic, tholeiitic, intrusive rocks
referred to collectively as either Nipissing Gabbro or Nipissing Diabase (Miller, 1911).
Considered to be a product of rift-related magmatism (Lightfoot and Naldrett, 1996),
these intrusions are dominantly dikes and sills of irregular shape, and where more or less
linear, they define a broad northeast-southwest trend (Fig. 1-2); faults (primarily
northeast-striking) and may have also played a role in controlling the emplacement of
some of the intrusions. Fieldwork indicates that locally, at the time of intrusion,
sedimentary strata were semi-lithified and that there was significant interaction between
Nipissing magmas and a relatively soft, water-rich sedimentary environment (e.g. Young,
1983; Shaw et al., 1999).
The majority of Nipissing Gabbro intrusions was emplaced into Archaean basement
rocks and sedimentary rocks of the Huronian Supergroup during a magmatic event that
spanned an interval of approximately 15 Ma between 2206 and 2221 Ma (Corfu and
Andrews, 1986; Noble and Lightfoot, 1992; Buchan et al., 1998). A summary of
geochronology on rocks of the Nipissing Gabbro suite is provided in Table 3-4. The
Nipissing Gabbro intrusions were emplaced into the Huronian Supergroup after early
deformation of the Huronian strata during the 2.45-2.3 Ga Blezardian Orogeny
(Stockwell, 1982), but prior to subsequent deformation and metamorphism during the
1.87-1.83 Ga Penokean Orogeny (Card et al., 1972; Morris, 1977). Young (1995)
suggested that some of the Nipissing Gabbro intrusions were emplaced into large-scale
early folds; folds that may have formed as a result of gravity-controlled mass movements
related to extensional tectonics.
Dike swarms similar in age and paleomagnetic pole position to the Nipissing Gabbro
suite include the Senneterre (2.216 Ga), Maguire (~2.23 Ga) and Klotz (2.21 Ga) dike
swarms, all located in the northeastern Superior Province (Buchan et al., 1998). It has
been suggested, mainly on the basis of paleomagnetic data, that there is a second age of
"Nipissing" intrusions, mostly northeast-trending dikes and possibly coincident in age
with the Biscotasing (2.167 Ga) dike swarm (e.g. Buchan and Card, 1985; Buchan et al.,
47
1993). The relationship of these younger "Nipissing" intrusions to the older, more
voluminous sills and intrusions of the Nipissing Gabbro suite have yet to be determined.
Location/Area Age +/- Span Method Ref. (Ma) (Ma) (Ma)
Bruce Mines-Blind River 2170 200 2370-1970 Rb/Sr;wr 1 Bruce Mines-Blind River 2155 80 2235-2075 Rb/Sr;wr 2 Bruce Mines-Blind River 2134 40 2174-2094 Rb/Sr;biotite 3 Bruce Mines-Blind River 1700 55 1755-1645 Rb/Sr;wr;feldspar 2
Gowganda 2162 27 2189-2135 Rb/Sr;wr 4 Gowganda 2116 27 2143-2089 Rb/Sr;wr 3
Wanapitei Lake 2109 40 2149-2069 K/Ar;wr 5 [Rathbun Lake intrusion]
Gowganda 2219.4 3.6/3.5 2223-2216 U/Pb, baddeleyite *6 [Miller Lake intrusion]
Wanapitei Lake 2210 4 2214-2210 U/Pb, baddeleyite *7 [Bonanza Lake intrusion]
New Liskeard/Cobalt 2217.2 4 2221.2-2213 U/Pb, baddeleyite *8 [Kerns intrusion]
New Liskeard/Cobalt 2209.6 3.5/4 2213.1-2206 U/Pb, baddeleyite *8 [Triangle Mountain intrusion]
*most reliable age constraints; wr = whole rock References: (1) Van Schmus et al. (1963); (2) Van Schmus (1965); (3) Buchan et al. (1989); (4) Fairbairn et al. (1969); (5) Rowell (1984); (6) Corfu and Andrews (1986); (7) Conrod (1989); (8) Noble and Lightfoot (1992)
Table 3-4. Summary of the geochronology on rocks from Nipissing Gabbro intrusions
located between Sault Ste. Marie and Cobalt, Ontario.
48
There are conflicting ideas regarding the tectonic setting and source of the Nipissing
Gabbro intrusions. Some workers have suggested that the Nipissing Gabbro intrusions
may represent the feeders of an eroded continental flood basalt system (e.g. Lightfoot et
al., 1987; Bennett, 1997). Alternatively, Fahrig (1987) proposed that a spreading-point
origin for Nipissing Gabbro intrusions was located west-southwest of the Sudbury area,
in the direction of an ocean opening, now represented by rocks of the Animikie Basin. In
contrast, Buchan et al. (1998) suggested a plume-induced, spreading-point origin well
northeast of Sudbury, with the Nipissing Gabbro intrusions being fed laterally by
Senneterre dikes which developed during the break-up of the eastern and northeastern
sides of the Superior Province; the break-up was purportedly initiated by the 2.22 Ga
Ungava and/or 2.17 Ga Biscotasing mantle plumes, located near present day Ungava
Bay. According to Buchan et al. (1998), the Nipissing Gabbro intrusions formed when
laterally-flowing magma, moving through Senneterre dikes, intersected favourable stress
regimes in the subhorizontal sedimentary strata of the Huronian Supergroup, some 1500
km from the proposed plume centre. Data from Anisotropy of Magnetic Susceptibility
studies by Ernst et al. (1999), show a dominantly horizontal flow regime, favouring the
linear source (i.e. dikes) model of Buchan et al. (1998) rather than the centralized plume-
related model (e.g. Lightfoot et al., 1987), which would have produced anisotropy results
indicating vertical flow regimes (i.e. cone sheets, extensive feeder dykes and lopolithic
bodies).
Conventional models for the Nipissing Gabbro suite involve an association with
plume-related magmatism, and are suggestive of an environment favourable for the
formation of economic concentrations of magmatic sulphide minerals rich in Cu-Ni-PGE
(e.g. Lightfoot et al., 1987; Vogel et al., 1998a). Moreover, there are several geochemical
and structural similarities between Nipissing Gabbro intrusions and the intrusions that
host the prolific Ni-Cu-PGE deposits in Noril’sk, Russia (e.g. Lightfoot and Naldrett,
1996) and the large, basin-related Ni-Cu-PGE deposits found in the Insizwa Complex,
southern Africa (e.g. Lightfoot et al., 1984). However, these same geochemical
signatures, which suggest continental flood basalt and mantle plume associations, are also
indicative of subduction related magmatism (i.e. boninites).
49
3.5 Matachewan and Hearst Dike Swarms
The Matachewan and Hearst dike swarms (also referred to as the Hearst-
Matachewan Swarm) cover an area of 500 to 700 km and together are the second largest
dike swarm in the Canadian Shield (Halls, 1988). In the southern Superior Province and
Southern Province of central Ontario, the dike swarm trend north to northwesterly and
have a U-Pb age of 2454±2 Ma (Heaman, 1988). Dikes are generally 10 m across, but up
to 250 m, have vertical to sub-vertical dips, are mainly quartz diabase and are commonly
characterised by blocky phenocrysts of saussuritized plagioclase crystals up to 20 cm in
length (Osmani, 1991). The southern convergence of the Matachewan and Hearst dike
swarms is consistent with a failed-arm environment, with a spreading point toward the
south (Osmani, 1991; Fahrig, 1987), approximating the region of northeast-southwest
Palaeoproterozoic rifting in the Sudbury area.
3.6 Sudbury Dike Swarm and Grenville Dike Swarm
Intrusions of the 1.24 Ga Sudbury Dike Swarm (Van Schmus, 1975; Krogh et al.,
1987) mark the last major magmatic activity in the Southern Province, crosscutting rocks
and structures of the Superior and Southern geological provinces. The dikes extend
southward into the Grenville Front Tectonic Zone of the Grenville Province where they
are displaced by faults related to the Grenville Orogeny. The Sudbury Dike Swarm
extends over a region of approximately 275 km and represents a relatively smaller mafic
event relative to larger dike swarms such as the Mackenzie Dike Swarm which is more
than 2,100 km long (Shellnutt, 2000). Rocks of the Sudbury Dike Swarm are typically
medium- to coarse-grained, olivine-magnetite gabbro dikes that strike ~310° and dip
~90°. The whole rock geochemistry of the Sudbury Dikes is consistent with ocean-island
alkaline basalt, transitional between alkaline and tholeiitic, with positive Eu anomalies
and a within-plate (intra-plate rift) tectonic setting (Shellnutt, 2000).
The Grenville Diabase Dike Swarm was emplaced at ~590 Ma (Kamo et al., 1995)
and is observed cutting country rock and a Sudbury swarm diabase dyke in the area of the
River Valley intrusion, Dana Township (Easton, 2003). Geochemical data on the
Grenville Diabase Dike Swarm in Dana Township are provided by Easton (2003).
50
3.7 Sudbury Igneous Complex
The Sudbury Structure has been variously interpreted as originating from meteorite
impact, impact-induced plutonism and volcanism, and volcanism (Pye et al., 1984).
Nonetheless, the Sudbury Structure is regarded by most as the deformed and eroded
remnant of a 200 to 250 kilometre diameter, multi-ring impact basin (Grieve, 1994),
deformed by Penokean tectono-metamorphism between 1.9 and 1.7 Ga (Easton, 2002).
The core lithologies of the structure, referred to as the Main Mass, are considered by
Lightfoot et al. (2000) to be differentiates of an impact melt sheet (silicates and
sulphides), essentially derived entirely from crustal lithologies (Keays and Lightfoot,
2004) and emplaced at 1.85 Ga (Krogh et al., 1984) into rocks of the Proterozoic
Southern and Archaean Superior geological provinces.
Overlying the Main Mass is the sedimentary Whitewater Group, which in-fills the
central depression immediately above the Sudbury Igneous Complex, and brecciated
footwall rocks around the Sudbury Igneous Complex. The Whitewater Group comprises
breccias of the basal Onaping Formation, pelagic metasedimentary rocks of the Onwatin
Formation, and meta-greywackes of the Chelmsford Formation (Dressler et al., 1991).
Young et al. (2001) interpreted the overlying sedimentary rocks of the Whitewater Group
to represent a preserved portion of a widespread flysch apron that would have spread
across the southern margin of the Superior Province as foreland basin fill, as a
consequence of the closure phase of the Wilson cycle during the Penokean Orogeny.
The southern part of the Sudbury Igneous Complex was weakly metamorphosed by
an event which also retrograded previously metamorphosed rocks of the Huronian
Supergroup, especially along major faults, at ~1.7 Ga (e.g. Schandl et al., 1994; Easton et
al., 1996; Fedo et al., 1997). Magmatism also occurred at 1.75 to 1.73 Ga and at 1.5 to
1.45 Ga in the Killarney Magmatic Belt southwest of Sudbury (van Breemen and
Davidson 1988; Krogh, 1994).
3.8 Regional Metamorphism and Structure
Mesoproterozoic rocks of the Grenville Province (Figs. 1-1 and 1-2) in the Sudbury
area consist mainly of metamorphosed Neoarchaean and Palaeoproterozoic rocks
(Easton, 1992, 2000b). In the Sudbury region, the Grenville Front Boundary Fault, which
marks the northern limit of the collisional Grenville and Penokean orogens at ~1.0 Ga
51
and ~1.75Ga, respectively, extends north-northeast from the northern USA, through the
area south of the Sudbury Igneous Complex, cutting across the northern portion of the
River Valley intrusion (Dana Lake area) and northeastward through the Province of
Quebec (Fig. 1-1). Immediately south of the Grenville Front Boundary Fault lies the
approximately 30 km wide Grenville Front Tectonic Zone (Fig. 1-2). Many lithologies
within the Grenville Front Tectonic Zone can be correlated on the basis of geochemistry
and geochronology with lithologies of the Southern and Superior provinces, including
rocks of both the East Bull Lake and Nipissing Gabbro suites (Easton, 1992, 2000b;
Corfu and Easton, 2001; Easton and Hrominchuk, 1999).
In the Southern Province, rocks of the East Bull Lake and Nipissing Gabbro suites
were affected locally by shock metamorphism at 1.85 Ga due to the Sudbury Event, and
regionally by folding and sub-greenschist to lower amphibolite facies metamorphism at
~1.84 Ga related to the Penokean Orogeny (Easton, 1992; James et al., 2002b). Within
the Grenville Province these same intrusions may have been locally recrystallized by
metamorphism at ~1.7 Ga and ~1.45 Ga, and at ~1.07 to 1.04 Ga by the Grenville
Orogeny (Corfu and Easton, 2001; Easton, 2000b).
With the exception of the central portion of the Southern Province, Nipissing Gabbro
intrusions were subjected to relatively low grades of metamorphism (sub- to lower
greenschist facies) and are little deformed (e.g. Card and Pattison, 1973; Card, 1978).
Within the central part of the Southern Province, between approximately Blind River and
Sudbury, East Bull Lake and Nipissing Gabbro intrusions and Huronian Supergroup
strata were subjected to low-pressure, regional metamorphism up to amphibolite facies
during the Penokean Orogeny (e.g. Card, 1978; Bennett et al., 1991). Although there is
field evidence that the East Bull Lake suite intrusions have been folded (e.g. Vogel et al.,
1998a), East Bull Lake suite and Nipissing Gabbro intrusions normally lack any
perceptible penetrative tectonic fabric, as noted in field observations during the course of
this study.
3.8.1 Regional Albitization
Several regional studies have characterized potassic and sodic metasomatism in the
Southern Province in Ontario and its potential relationship to felsic plutonism and arc
collision (e.g. Siemiatkowska and Martin, 1975; Gates, 1991; Schandl et al., 1994; Fedo
52
et al., 1997). One such study (Gates, 1991), aimed at documenting Au and base metal
mineralization associated with widespread albitization (sodic metasomatism and/or
fenitization), demonstrated a relationship between Au and Ni-Cu±Co sulphide
mineralization, and localized albitization in the area stretching from Temagami (east of
Sudbury) to the Bruce Mines area (west of Sudbury). Schandl et al. (1994) determined a
U-Pb age of 1700 ±2 Ma for albitized rocks associated with a Au mineralizing event in
the Wanapitei Lake area, east of Sudbury; this age suggests that the albitization event was
coeval with a period of granitic plutonism in the Southern Province between 1750 and
1700 Ma (van Breemen and Davidson, 1988; Davidson et al., 1992). Schandl et al.
(1994) concluded that the presence of fine-grained hydrothermal monazite,
fluorocarbonates (bastnäsite and synchysite) and an Y-REE mineral (gadolinite),
combined with elevated rare earth element (REE) concentrations, and the disparity
between the age of albitization (~1700 Ma) and ages (2700, 1800-1900 and 1100 Ma;
Sage, 1991) of known carbonatite-alkalic complexes in the region, suggested that
sodium-rich fluids may have been generated by alkalic or carbonatitic rocks at depth.
Schandl et al. (1994) also demonstrated a positive correlation between Au and Co that
was independent of Na2O, suggesting that the concentration of Au did not occur during
the albitization but was coeval with the partial replacement of albite by chlorite and (or)
sulphides. On the basis of this positive Au-Co correlation, Schandl et al. (1994)
suggested that the Au was more than likely concentrated to economic grade by Co-±Ni-
bearing low pH fluids, which precipitated the Au together with some of the secondary
sulphide and chlorite minerals, utilizing the fractured, albitized rocks (caused by high pH
or peralkaline fluids) that acted as conduits for the mineralizing fluids.
3.8.2 Murray Fault System
The Murray Fault System (or Murray Fault Zone), extending for more than 150 km
through the Southern Province, south of Sudbury and westward along the north shore of
Lake Huron toward Sault Ste. Marie (Figs. 1-1 and 1-2), is a major dextral strike-slip
structure of ductile shear (Williams et al., 1991). Card et al. (1972) suggested, in addition
to being a major regional structure, the Murray Fault System also acts as a distinct
paleoenvironmental facies marker with rocks north of the Murray Fault System
53
interpreted as fluvial and those south of it as deep-water turbidites; this interpretation
implies that the Murray Fault System was active during Huronian Supergroup deposition.
The Murray Fault System marks an abrupt change from dominantly sedimentary and
relatively unstrained, sub-greenschist facies (5 km burial depth) rocks to the north, and
highly strained, lower to middle amphibolite facies (15 to 20 km burial depth) volcanic-
sedimentary rock sequences to the south (Bennett et al., 1991); dip-slip movements of
approximately 10 to 15 km are indicated by this metamorphic distinction. Sedimentary
sequences of the Huronian Supergroup are for the most part thickest in regions south of
the Murray Fault System. Zolnai et al. (1984) suggested that the sedimentary rocks south
of the Murray Fault System accumulated to greater thicknesses than those north of the
Murray Fault System. Subsequently, rocks south of the Murray Fault System were
tectonically buried to middle crustal depths and were then thrust up and over adjacent
Huronian Supergroup rocks to the north along the Murray Fault System; ensuing erosion
would have produced the present day configuration.
East of Sudbury, near the town of Coniston, the Grenville Front Boundary Fault and
the Murray Fault System are thought to merge into the Wanapitei Fault (Davidson, 1997).
This fault can be traced through Street Township, then eastward where it is referred to as
the Ess Creek and Grenville Front Boundary faults (Fig. 1-2), and following the trend of
the Kabikotitwia and Sturgeon Rivers (Easton and Murphy, 2002). Easton et al. (2004)
considered all Huronian strata located west and northwest of the Wanapitei and Ess
Creek faults as north of the Murray Fault System and all Huronian strata preserved within
the Grenville Province to have been originally deposited south of the Murray Fault
System.
54
CHAPTER 4: NIPISSING GABBRO INTRUSIONS
4.1 General Geology and Regional Morphology
The ~2.2 Ga Nipissing Gabbro intrusions are associated with and intrude the
sedimentary rocks of the Huronian Supergroup and their Archaean granite-greenstone
basement rocks within the Southern Province of Ontario (Fig. 1-2). For the most part,
intrusions in the Sault Ste. Marie-Elliot Lake area (Fig. 1-1), north of the Murray Fault
Zone and within several kilometres west of the Sudbury Igneous Complex, are
considered to be weakly to moderately deformed (Fig. 1-1). This contrasts with
intrusions in the Sudbury-Espanola area (Fig. 1-1), south of the Murray Fault Zone,
which are interpreted to be moderately to highly deformed. Contrasting these are
exposures of Nipissing Gabbro intrusions that occur in the belt of Huronian sedimentary
rocks south and southwest of the Sudbury Igneous Complex and north of the Murray
Fault Zone (Figs. 1-1 and 1-2) which are little to moderately deformed. Nipissing
Gabbro intrusions located northeast of the Sudbury Igneous Complex and within the
Cobalt Embayment (Fig. 1-1) are considered to be weakly deformed to locally
undeformed.
In general, it appears as though deformed Nipissing Gabbro intrusions are hosted by
lower sequences of Huronian Supergroup rocks, whereas the relatively undeformed
intrusions are hosted by upper sedimentary sequences. This disparate degree of
deformation and the association with different levels of Huronian Supergroup rocks
suggests that higher level Nipissing Gabbro intrusions are generally less deformed than
those emplaced and subsequently exhumed from lower stratigraphic levels. This may
also in part be related to primary features (i.e. structures and sedimentary bedding planes)
that developed at various stratigraphic depths within the rift basin sedimentary sequences,
controlling the initial emplacement of the Nipissing Gabbro magmas.
4.1.1 Local Morphology
Although many of the Nipissing Gabbro intrusions have been somewhat
metamorphosed and deformed, some of the intrusions are thought to have retained their
primary morphologies as reflected by the current outcrop patterns. Outcrop patterns of
Nipissing Gabbro within the study area include tabular intrusions, open ring structures,
55
and massive irregular shaped bodies (Figs. 1-2 and 5-1). These outcrop patterns are
interpreted to represent four main morphologies (Jambor, 1971; Buchan et al., 1989): (1)
undulating sills and dikes; (2) concordant homogenous sills; (3) cone sheets or ring dikes;
and, (4) lopolithic-like or thick stock-like bodies. Horst and graben structures (block-
faulting) also appear to play a major role in determining the level of stratigraphy of each
intrusion through the study area, and particularly in the regions southwest, south and east
of Sudbury (Fig. 1-2).
The majority of Nipissing Gabbro intrusions are interpreted to occur as near-
horizontal sheets or undulating sills (Fig. 4-1), consisting of basins and arches, and near-
vertical dikes, that are predominantly less than 1000 metres thick (Hriskevich, 1968;
Jambor, 1971; Conrod, 1988, 1989). Disseminated to massive Cu-Ni-PGE sulphide
mineralization in these types of intrusions is concentrated within the basin or limb
portions and pods of dominantly massive pyrrhotite occurring within the arches. Much of
the mineralization is associated with a thick (generally >100 m) orthopyroxene gabbro
unit (Lightfoot and Naldrett, 1996; Jobin-Bevans et al., 1998, 1999). Examples of this
form include the Appleby, Basswood, Louie Lake, and Makada Lake intrusions (Fig. 1-
2).
Tabular homogeneous sills form a second type of intrusion that was recognized in
the study area. These types of intrusions extend in a tabular (linear) manner for several
hundred metres to several 10’s of kilometres and include the Charlton Lake (Casson
Lake), Bell Lake (Nairn), and Manitou Lake intrusions (Fig. 1-2). The gabbroic rocks
within these intrusions exhibit very little across-strike differentiation and remarkable
homogeneity along strike.
Arcuate and open-ring outcroppings of Nipissing Gabbro, described by Buchan et al.
(1989) as cone sheets, comprise a third form of intrusion. These forms are distinguished
by structural features in surrounding sedimentary rocks that suggest the gabbro in these
types of intrusions were emplaced as shallow (<50°), inward-dipping, cone-shaped
intrusions that are tens of metres to several hundred metres thick (Jambor, 1971; Lovell
and Caine, 1970; Jobin-Bevans et al., 1998). These types of intrusions contain
disseminated and blebby sulphides hosted in orthopyroxene gabbro, occurring within a
56
few hundred metres of the basal contact of the intrusions. Examples of this form include
the Kukagami Lake (Photo 4-1) and Rathbun Lake intrusions (Figs. 1-2 and 5-1).
Photo 4-1. Kukagami Lake sill “Kukagami Cliff Section” – the southward dip is apparent
(~40 degrees) as defined by the regular jointing; looking east at south-dipping sill. The
maximum height of the hill is about 15 metres. The approximate trace of the basal
contact is shown.
57 57
58
The fourth type of intrusion, the lopolithic-like form (i.e. saucer-shaped), is rare and
is interpreted to represent deeper “feeder” systems to the stratigraphically higher sill, dike
and cone sheet type of intrusions. These deeper exposures, which are fault bound on a
regional scale, are thought to have been exposed through uplift along the bounding fault
lines (Dressler, 1979; Innes and Colvine, 1979; Jobin-Bevans et al., 1998). In the
lopolithic-like form, disseminated, semi-massive and massive sulphide mineralization is
hosted by orthopyroxene gabbro within tens of metres of the footwall sedimentary rocks,
and within topographic irregularities along the footwall contact. An example of this form
is the Chiniguchi River intrusion in Janes Township (Figs. 1-2 and 5-1).
Contacts between intrusions and the dominantly sedimentary country rocks are not
well exposed and are generally characterized by swampy or low lying areas adjacent to
elevated outcrops of Nipissing Gabbro intrusive rocks or sedimentary rocks. Types of
observable contacts are variable but most commonly comprise sharp, straight contacts
cross-cutting Huronian Supergroup sedimentary rocks and conformable, sill-like contacts
following the bedding of the host Huronian Supergroup rocks (Photo 4-2a); other contact
types include faults and irregular, tongue-like protrusions of Nipissing Gabbro cutting
into Huronian Supergroup rocks (Photo 4-2b); similar contact types were observed by
Conrod (1988).
4.2 General Stratigraphy
The general stratigraphy of Nipissing Gabbro, which has been described in previous
reports (e.g. Hriskevich, 1968; Conrod, 1988; Lightfoot and Naldrett, 1996), is
remarkably consistent within individual intrusions, particularly where the intrusion is
well-differentiated (Fig. 4-2). Small-scale folds are rare in Nipissing Gabbro intrusions
and any recognizable folding appears to be related to large-scale, regional events.
Consequently, the observed stratigraphy within individual intrusions is interpreted to
reflect the original arrangement of layers within magma chambers. The varying
proportion of differentiates and/or hybrid rocks (granophyre, aplite, granite, granodiorite)
versus orthopyroxene gabbro and gabbro in any given intrusion may reflect the reactivity
of the country rock with the magma and the degree of local assimilation and/or
contamination.
59
Photo 4-2. (A) Looking north toward a conformable, sill-like contact that follows the bedding of
the host Huronian Supergroup sedimentary rocks, south end of the Rauhala property, Waters
Township. The contact region is indicated by the white dashed line. The height of the overlying
gabbro unit is about 2 metres. (B) Irregular contact of Nipissing Gabbro cutting into Huronian
Supergroup sedimentary rocks from outcrops near the Grenville Front Boundary Fault, west of
Hwy #805 in the eastern part of Janes Township. The Canadian one dollar coin is about 2.5 cm in
diameter.
60
61
Alternatively, the differing proportion may reflect the relative position of the section
and/or its current level of erosion, and therefore surface exposure, through the intrusion,
if convection played a major role in the development of the intrusion (Conrod, 1988;
Lightfoot and Naldrett, 1989).
Previous work by Jambor (1971), Conrod (1988) and Lightfoot and Naldrett (1996)
produced a type-stratigraphy for Nipissing Gabbro intrusions. This current study, which
integrates geological surface mapping, ground geophysical surveys and diamond drill
hole data, allows for refinement of the stratigraphy into 5 major units (Fig. 4-2). Most of
the major units have good lateral and vertical continuity but individual layers within these
major units can show significant petrologic variations in modal mineralogy and/or
thickness.
Igneous layering is inconspicuous in all of the major units, but where observed, is
typically developed on a centimetre- to decimetre-scale (Photo 4-3). Metre- or
decametre-scale layering may in fact constitute the main style but is less discernable than
the former types due to poor surface exposure; larger-scale layering is more apparent in
drill core intersections. Layering is primarily defined by modal variations in plagioclase
and pyroxene abundance, occasionally by conspicuous concentration of sulphide minerals
(Photo 4-3), and less commonly by an increase in oxide minerals such as magnetite
and/or ilmenite. Textural layering, defined by distinct grain-size variations, has been
recorded in the Nipissing Gabbro suite in a number of localities (e.g. Conrod, 1988; Card
et al., 1975); in the current study area, textural layering has been documented in several
areas (Photo 4-4) but for the most part it is rarely observed. Layering usually strikes
parallel to the upper and lower contacts of the sills and dips range from near vertical to
near horizontal, dependent on the overall orientation and geometry of the intrusive body,
and is often mimicked by strong joint patterns (Photo 4-1).
Most of the Nipissing Gabbro intrusions in the study area show very little
differentiation, consisting almost exclusively of medium-grained gabbro and/or
orthopyroxene gabbro with subordinate quartz gabbro, gabbro-leucogabbro and vari-
textured gabbro. Changes in the stratigraphy are interpreted to mainly represent
decametre-scale layering.
62
Photo 4-3. (A) and (B) Modal and textural layering in Nipissing Gabbro at the Big Swan
property, Porter Township. Note the layer of sulphide-rich, medium- to coarse-grained
gabbro (vari-textured gabbro) in contact with a layer of relatively sulphide-poor, fine- to
medium-grained gabbro. The blue areas are paint for marking the sampling grid. The
hammer handle is about 33 cm long.
63
Photo 4-4. Conspicuous textural layering in outcrop at the Rauhala property, Waters
Township. The hammer handle is about 70 cm long.
Less commonly, some of the intrusions are well differentiated, ranging upward in
composition from basal quartz diabase and/or gabbro which may or may not be chilled,
orthopyroxene gabbro, gabbro, gabbro-leucogabbro, vari-textured gabbro, granophyric
gabbro (includes aplite, granodioritic to granitic rocks and pegmatitic gabbro), and an
upper quartz diabase and/or gabbro which may or may not be chilled (Fig. 4-2). Narrow
(<0.5 m wide), fine-grained gabbro (diabase) dikes are observed cutting through the
orthopyroxene gabbro, gabbro and gabbro-leucogabbro units. In most cases, detailed
characterization of the contacts between each of the major units in the igneous
stratigraphy is made difficult by lack of exposure. However, contacts are generally
transitional, implying a gradational change in composition between the major units (Fig.
4-2).
64
4.2.1 Lower & Upper Quartz Diabase-Gabbro Units
Where present, the lower (basal) and upper (capping) quartz diabase to quartz gabbro
units are massive, fine-grained to aphanitic (chilled), and contain <1% fine-grained pyrite
and/or pyrrhotite with rare chalcopyrite. The chilled margin that develops at the contact
with the country rock is normally <20 cm wide and may host anastomosing quartz-
carbonate veins, developed as a result of fracture-fill and/or patches rich in medium-
grained quartz, which is likely a result of localized crustal contamination. The chill is
petrologically equivalent to the fine-grained gabbro dikes, which are observed (rarely) in
the upper parts of the stratigraphy.
Gabbro-sediment breccia is relatively rare and is mainly observed in drill core
samples and only rarely in outcrop. The breccia, which is akin to the Footwall Breccia
Unit described in the River Valley intrusion (see Section 6), occurs proximal to the basal
contact of the intrusions, extending into the footwall rocks (Photo 4-5); these breccias
have been observed at the upper contacts of the intrusions where they extend into the
hangingwall. Sulphide-bearing basal breccia consists of about 60% angular to sub-
angular sediment fragments and about 10% sub-angular to sub-rounded gabbro fragments
within a white to grey, siliceous (minor carbonate), fine-grained (cherty?) cement (Photo
4-6). These basal breccias are locally mineralized with 1-5% disseminated chalcopyrite,
pyrrhotite and pyrite and rarely, semi-massive to massive veins of chalcopyrite,
pyrrhotite and pyrite. These semi-massive to massive sulphide veins are secondary
sulphides, cutting through the lower quartz diabase unit, the overlying transition zone and
extending into or out of the basal portion of the orthopyroxene gabbro unit (e.g. Rathbun
Lake occurrence, Rathbun Township and Rauhala property, Janes Township; Figs. 1.2
and 5-1).
The lower quartz diabase grades upward from chilled to fine-grained nearest the base
to a transition zone of fine-grained and locally medium-grained gabbro that merges into
the overlying orthopyroxene gabbro unit. Lightfoot and Naldrett (1996) described an
upward increase in quartz content toward the overlying orthopyroxene gabbro unit but
this was not observed in this study. The upper quartz diabase, although not as well
defined as the lower quartz diabase and usually absent, is in sharp contact with the
underlying granophyric gabbro.
65
Photo 4-5. (A) and (B) Gabbro-sediment breccia occurring along the contact of a Nipissing
Gabbro intrusion in Porter Township, near the Big Swan property. The matrix in the breccia
consists of fine-grained pyroxenitic gabbro and shares many textural similarities with Sudbury
Breccia which occurs in the region. The gabbro inclusion at the foreground in photo (B) is
labelled as Nipissing Gabbro but may be a fragment of East Bull Lake suite intrusion gabbro. The
hammer handle is about 33 cm long.
66
Photo 4-6. Sulphide-bearing basal breccia in drill core from the Rastall occurrence, Janes
Township. The pen magnet is about 12.5 cm long.
4.2.2 Orthopyroxene Gabbro (Gabbronorite) Unit
The orthopyroxene gabbro unit (Photo 4-7) has been previously referred to as the
hypersthene zone (Conrod, 1988), gabbronorite (Conrod, 1989), and as both hypersthene
gabbro and gabbronorite (Lightfoot and Naldrett, 1996). This unit consists primarily of
massive, medium-grained, orthopyroxene-bearing gabbro (>10% orthopyroxene
phenocrysts), commonly containing trace to ~1% disseminated sulphide but in many
cases containing 1-5% disseminated and blebby chalcopyrite and pyrrhotite (Photos 4-7a
and 4-8). Rare semi-massive to massive pods, ranging from centimetre- to metre-scale,
of chalcopyrite and/or pyrrhotite are observed and interstitial blue quartz may be
associated with sulphide minerals. In some parts of the study area (e.g. the Makada Lake
intrusion), the orthopyroxene gabbro unit contains metre-scale domains of altered, vari-
textured gabbro that appear to occur at the interface with the overlying gabbro unit; this
variability can make identification of the orthopyroxene unit problematic at the sub-metre
67
outcrop scale. Orthopyroxene gabbro weathers dark grey to brown, commonly with
distinct brown to honey-brown phenocrysts of orthopyroxene (Photo 4-9a) and/or
pseudomorphs of tremolite-actinolite and talc after orthopyroxene (Photo 4-7b).
Subordinate rock types include discontinuous layers or pods of melagabbro (>55 to 90%
mafic minerals) and/or pyroxenite.
Centimetre- to metre-scale, modal igneous layering can be present in this unit, but it
is poorly defined and is best discriminated by the presence of centimetre- to decimetre-
scale repeating joints that parallel what is likely the igneous layering and its associated
cooling fronts (Photo 4-1). Rare mafic fragments occur in some of the intrusions,
generally proximal to the basal contact (Photo 4-9b). Within the upper part of this unit
and transitional into the gabbro unit, is an oxide-bearing (1-10% total oxide) gabbro to
orthopyroxene-gabbro. This oxide-bearing gabbro layer has not been recognized in many
of the intrusions, but in the few areas where it does occur (e.g. the Kukagami Lake
intrusion), it has been traced in outcrop for more than 3 km along strike. This unit may
represent a marker horizon that developed in some of the intrusions where fractionation
led to Fe-enrichment in the liquid and concentrated precipitation of oxide minerals
(magnetite > titanomagnetite > ilmenite). The orthopyroxene gabbro is gradational into
the overlying gabbro, marked by a distinct decrease over several centimetres in the
orthopyroxene content, and in particular a decline in the percentage of orthopyroxene
phenocrysts.
4.2.3 Gabbro Unit
The gabbro unit consists of massive, medium-grained, gabbro (25 to <55% mafic
minerals), containing localized <1% disseminated chalcopyrite and pyrrhotite and
subordinate blebby pyrrhotite and chalcopyrite; interstitial blue quartz may be associated
with the sulphide. Centimetre-scale modal layering is rarely observed. Subordinate rock
types include melagabbro and leucogabbro (10 to <25% mafic minerals). Within the
upper part of the gabbro unit and transitional into the gabbro-leucogabbro unit, is an
oxide-bearing (1 to 10% total oxide) gabbro to leucogabbro.
68
Photo 4-7. Orthopyroxene-gabbro unit typically found within the lower portions of Nipissing Gabbro intrusions. (A) Medium-grained orthopyroxene gabbro with sulphide staining from Trench 1 at the Rastall occurrence, Janes Township. The Canadian one dollar coin is 2.5 cm in diameter. (B) Medium-grained porphyritic orthopyroxene gabbro with pseudomorphs of tremolite-actinolite and talc after orthopyroxene (hypersthene), from outcrop along Hwy #805, near the Grenville Front Boundary Fault in eastern Janes Township. The Canadian one dollar coin is about 2.5 cm in diameter.
69
Photo 4-8. (A) Typical disseminated and blebby sulphide mineralization in medium-
grained orthopyroxene gabbro from the Rastall occurrence (Trench 1), Janes Township.
The Canadian one dollar coin is about 2.5 cm in diameter. (B) Fine- to medium grained
orthopyroxene gabbro with atypical total disseminated sulphide (>10% sulphide) from
the Rastall occurrence (Trench 4), Janes Township. The Canadian one dollar coin is
about 2.5 cm in diameter.
70
Photo 4-9. Orthopyroxene Gabbro Unit. (A) Typical unmineralized, medium-grained
orthopyroxene gabbro with dark brown weathering and distinct brown to honey-brown crystals of
orthopyroxene (hypersthene), generally recessed due to weathering. A centimetre ruler is
provided for scale. (B) Mafic fragment in medium-grained orthopyroxene gabbro to gabbro,
located proximal to the contact with Huronian Supergroup sediment, Porter Township. The
Canadian two dollar coin is about 2.8 cm in diameter.
71
This oxide-bearing layer, which commonly occurs about half to two thirds of the way up
through the exposed stratigraphy, has only been recognized in a few of the intrusions.
However, as with the oxide-bearing gabbro layer at the top of the orthopyroxene gabbro
unit, this unit may represent a marker horizon that developed through Fe-enrichment in
the liquid and subsequent precipitation of oxide minerals (magnetite > titanomagnetite >
ilmenite). The gabbro unit is gradational into the overlying gabbro-leucogabbro, marked
by a gradual increase, over tens of centimetres, in the percentage of plagioclase feldspar
(relative to mafic minerals) and from time to time, the presence of an oxide-bearing
gabbro; the latter may be attributed to a change (increase) in the fugacity (activity) of
oxygen (fO2).
4.2.4 Gabbro-Leucogabbro Unit
This unit is characterized by massive to crudely layered, medium-grained gabbro and
medium-grained leucogabbro. Layering is defined by modal changes in the ratio of
plagioclase and amphibole (after pyroxene) and is commonly decimetre- to metre-scale.
The gabbro-leucogabbro unit contains trace sulphide dominated by disseminated to
blebby pyrrhotite and subordinate chalcopyrite and pyrite. Subordinate rock types
include anorthosite (<10% mafic minerals) and very rarely orthopyroxene gabbro. The
gabbro-leucogabbro unit is gradational into the overlying vari-textured gabbro, marked
by a gradual increase in irregular patches of coarser-grained gabbro.
4.2.5 Vari-Textured Gabbro Unit
As the name implies, the vari-textured (variably textured) unit comprises a textural
mixture of massive gabbroic (gabbro to leucogabbro) rocks, ranging from fine-grained to
coarse-grained (Photo 4-10), with localized, metre-scale regions of gabbro pegmatite;
rare, localized, metre-scale patches or pods of melagabbro were also observed. The
highly variable nature of this unit and general lack of surface exposure, makes field
identification of this unit difficult. This unit generally contains localized trace
disseminated pyrrhotite and chalcopyrite. Gabbro pegmatite contains up to 5% coarse-
grained (>1 cm diameter) blebby and ragged chalcopyrite and pyrrhotite. The vari-
textured gabbro and overlying granophyric gabbro unit are separated by a transition zone
which is characterized by an upward increase, over several tens of centimetres, in
72
granophyric textures including micropegmatite and miarolitic cavities, pegmatitic
segregations and aplite dikes.
Photo 4-10. Vari-textured Gabbro Unit. (A) Vari-textured gabbro from outcrop in the
Basswood Lake Intrusion, Wells Township. (B) Close-up of coarser-grained gabbro
patches from the same outcrop as (A). A centimetre ruler is provided for scale.
73
4.2.6 Granophyric Gabbro Unit
This uppermost major unit consists of a variety of rock types including massive,
medium- to coarse-grained granophyric gabbro, gabbro to leucogabbro pegmatite, quartz
gabbro, aplite dikes and localized gabbro-sediment breccia. Myrmekitic textures and
miarolitic cavities up to several centimetres in diameter are common, consisting of
quartz, alkali feldspar and carbonate. Lightfoot and Naldrett (1996) described similar
features in the granophyric gabbro unit. The frequent occurrence of gabbro pegmatite
(Photo 4-11), aplite and aplite dikes, granophyric pods and/or dykes (Photo 4-12) and
miarolitic cavities (Photo 4-13a) in the upper sections of Nipissing Gabbro suggests a
well fractionated magma enriched in volatiles at the time of crystallization. In addition,
the siliceous nature of these rocks, along with localized but extensive alteration (i.e.
potassic), and alkali-rich rock types suggests contamination through stoping and
assimilation of the hangingwall country rocks. Massive, pyrrhotite-dominated sulphide
pods, up to 4 metres diameter have been observed in outcrop (e.g. Louie Lake, Louise
Township and Rauhala property, Waters Township) and are commonly located within
tens of metres of the contact with country rocks or in regions inferred to be proximal to
the now eroded hangingwall units. The granophyric gabbro unit contains patches,
generally less than a few metres in strike and width, that contain about 1-3%
disseminated and blebby pyrrhotite, chalcopyrite and pyrite, which may be associated
with interstitial and centimetre-scale patches of blue quartz (Photo 4-13b). Pyrite is
relatively common as fine-grained disseminations and smears along fracture planes.
The upper contact of the granophyric gabbro unit is highly variable; characterizing
this contact region is hampered by a lack of exposure and/or a significant amount of
erosion which has removed this level of the stratigraphy. Aplite dikes, which consist of
plagioclase, alkali feldspar and quartz, can be traced from within the granophyric gabbro
unit, into the hangingwall sedimentary rocks, cross-cutting the chilled margin or upper
quartz diabase-gabbro. Partially assimilated rafts of hangingwall sedimentary rock,
ranging from centimetre- to metre-scale, are common nearer the upper contact. Similar
features were noted by Lightfoot and Naldrett (1996) and Conrod (1988, 1989).
74
Photo 4-11. (A) Gabbro pegmatite, termed “snowball” gabbro from what is interpreted as
the uppermost stratigraphy of the Makada Lake Nipissing Gabbro body in Waters
Township. The pencil is about 15 cm. Photo (B) is a close up of the “snowballs” which
consist of feldspar and quartz “eyes” in a mafic matrix. The Canadian two dollar coin is
about 2.8 cm in diameter.
75
Photo 4-12. Granophyric Gabbro Unit. (A) Granophyric pod (or dike?) from the upper
portion of the Basswood Lake Intrusion, Wells Township. Note the darker, mafic
(amphibole) rich selvages running the length of the granophyric pod and within a narrow
band nearer the hammer. The hammer handle is about 70 cm long. (B) Close up of photo
(A) showing mafic inclusion within medium- to coarse-grained granophyric gabbro.
76
Photo 4-13. Granophyric Gabbro Unit. (A) Miarolitic cavity lined with carbonate and
quartz and hosted by pyrite-bearing granophyric gabbro in the Basswood Lake Intrusion,
Wells Township. (B) Patchy sulphide mineralization (mainly pyrite with subordinate
chalcopyrite) associated with blue to grey quartz in the Basswood Lake Intrusion. A
centimetre ruler is provided for scale.
77
4.3 Petrography and Mineralogy
Each stratigraphic unit is characterized by a more or less distinct assemblage of
minerals, alteration styles and associated sulphide and/or oxide minerals. Previous work
describing the petrological and mineralogical variations through Nipissing Gabbro
intrusions includes Hriskevich (1968); Card and Pattison (1973); Conrod (1988, 1989);
and, Lightfoot and Naldrett (1996). A synopsis of the mineralogic and petrographic
features of the rocks is provided in Appendix 2.
Plagioclase feldspar, clinopyroxene and orthopyroxene are the main primocryst
phases forming the rocks of Nipissing Gabbro intrusions; amphibole and magnetite are
late interstitial and/or minor cumulus phases. Plagioclase and clinopyroxene (principally
augite) are modally the most abundant and consequently gabbro is the most common rock
type. Phenocrysts of orthopyroxene (hypersthene) are the distinguishing feature in the
orthopyroxene gabbro unit where they comprise up to 10% of the mode. The presence of
these phenocrysts contributes to the higher MgO compositions of these rocks.
Conrod (1988, 1989) noted the presence of olivine in the “hypersthene zone”, which
is equivalent to the orthopyroxene gabbro unit, and in the chilled basal quartz diabase at
the Cross Lake Intrusion, located near Temagami Lake, east of the current study area;
Hriskevich (1968) made similar observations on rocks from the Cobalt area. However,
no olivine-bearing rocks were observed in either hand specimen or thin section during the
course of this study. The presence of olivine in the chilled diabase, as described by
Conrod (1988, 1989), suggests that olivine was a pre-emplacement, crystallizing phase,
entrained in the early magma.
In general, plagioclase feldspar is altered to saussurite (epidote + clinozoisite),
±chlorite and ±sericite; orthopyroxene to uralite (tremolite-actinolite), tremolite-
actinolite, ±chlorite and rarely talc; clinopyroxene to uralite, tremolite-actinolite,
±chlorite and ±blue-green hornblende; and, olivine to talc-serpentine (±antigorite) and
magnetite assemblages (Conrod, 1988, 1989). Greenschist to amphibolite facies
metamorphism played some role in the development of the observed alteration
assemblages, but the lack of ubiquitous alteration in all lithologies – where present, the
majority of unaltered minerals occur within the central parts of the intrusions - suggests
that localized hydrothermal and deuteric alteration, through the introduction of water,
78
silica and carbon dioxide, were the dominate processes. In the descriptions that follow,
the mineral mode by volume percent is specified in parentheses.
4.3.1 Lower & Upper Quartz Diabase-Gabbro Units
These units consist almost entirely of long, radiating plagioclase (40%) and pyroxene
(40%) crystals that together with quartz (10%) and granular interstitial pyroxene (10%)
form a diabasic texture (Photo 4-14). Augite and pigeonite are the main pyroxene
minerals and quartz may occur as discrete grains or as aggregates in association with
potassium feldspar in micropegmatite, granophyre and myrmekitic intergrowths.
Magnetite (titanomagnetite) and subordinate ilmenite form the principal opaque minerals
and accessory minerals include apatite, epidote and rarely titanite. Plagioclase
phenocrysts average about 1.0 mm in diameter and constitute as much as 10% of the
mode. Pyroxene phenocrysts are <0.5 mm in diameter, are rarely observed, and occur in
<5% of the mode; Lightfoot and Naldrett (1996) noted 0.5 mm olivine phenocrysts
altered to antigorite clouded with magnetite. Very fine-grained (<0.1 mm) amphibole
(uralite) and chlorite occur as alteration products after pyroxene and sericite, epidote and
clinozoisite occur as alteration products after plagioclase.
4.3.2 Orthopyroxene Gabbro (Gabbronorite) Unit
This unit is dominated by laths of euhedral plagioclase (55%) and equant subhedral
clinopyroxene grains (35%) which are often enclosed by larger subhedral orthopyroxene
(5-10%) grains. Accessory phases include quartz, biotite, ilmenite and apatite.
Infrequently, this unit contains well-preserved cumulus igneous mineral assemblages
consisting of euhedral clinopyroxene and orthopyroxene with interstitial plagioclase
(Photo 4-15). Olivine was noted by Conrod (1988) but is absent or not recognisable due
to extensive alteration, in any of the samples from this study. Orthopyroxene forms the
most common phenocrysts, averaging about 1.0 mm in diameter and occurring as
equidimensional, subhedral to euhedral grains. Individual columnar, euhedral
phenocrysts from the Kukagami Lake intrusion are up to 5 mm in length. Commonly,
fine-grained amphibole, uralite and chlorite occur as alteration products after pyroxene
(Photo 4-16), minor antigorite and talc/serpentine after orthopyroxene, and sericite,
epidote and clinozoisite occur as alteration products after plagioclase.
79
Photo 4-14. Lower and Upper Quartz Diabase-Gabbro Units. (A) Chilled marginal quartz
gabbro (Makada Lake Intrusion, Waters Township) with typical gabbroic texture,
consisting of radiating plagioclase (plag), pyroxene (pyx), and quartz, and phenocrysts of
pyroxene (p-pyx). Plane light. (B) Same view as (A) but in crossed polars. Field of view
is 8 mm wide for both photographs.
80
Photo 4-15. Orthopyroxene Gabbro (Gabbronorite) Unit - atypical. (A) Euhedral
clinopyroxene (cpx) and orthopyroxene (opx) with interstitial plagioclase (plag).
Accessory phases include quartz, biotite, ilmenite and apatite. Plane light. (B) Same view
as (A) but in crossed polars. Field of view is 8 mm wide for both photographs.
81
Photo 4-16. Orthopyroxene Gabbro (Gabbronorite) Unit - typical. (A) Groundmass and phenocrysts of pyroxene (p-pyx) are commonly replaced by fine-grained amphibole, uralite and chlorite, and sericite, epidote and clinozoisite occur as alteration products after plagioclase (plag). The phenocrysts (p-pyx) were most probably originally hypersthene. Plane light. (B) Same view as (A) but in crossed polars. Field of view is 8 mm wide for both photographs.
82
4.3.3 Gabbro Unit
This unit consists of a relatively uniform distribution of euhedral plagioclase laths
(55%) and equant subhedral clinopyroxene (45%); accessory phases include quartz,
biotite, ilmenite, apatite and rare titanite. Mineralogy in this unit is relatively fresh in
comparison to other units. Amphibole and chlorite occur as alteration products after
pyroxene and sericite, epidote and clinozoisite occur as alteration products after
plagioclase.
4.3.4 Gabbro-Leucogabbro Unit
This unit is characterized by variable percentages in euhedral plagioclase laths (45-
75%) and equant subhedral clinopyroxene (25-55%); accessory phases include quartz,
biotite, ilmenite, apatite and rare titanite. Mineralogy in this unit is relatively fresh in
comparison to other units. Amphibole and chlorite occur as alteration products after
pyroxene and sericite, epidote and clinozoisite occur as alteration products after
plagioclase.
4.3.5 Vari-Textured Gabbro Unit
The vari-textured unit consists mainly of elongate, subhedral to euhedral plagioclase
(45%) and subhedral to anhedral pyroxene (45%) crystals which together with quartz
(5%) and granular interstitial pyroxene (5%) form a gabbroic texture; augite is the main
pyroxene mineral. Clinopyroxene forms oikocrystic textures with the plagioclase laths.
Micropegmatite and myrmekitic intergrowths are also noted. Accessory phases include
alkali feldspar, apatite, ilmenite, magnetite (titanomagnetite) and biotite. This unit is
consistently altered with fine-grained amphibole, uralite and chlorite occurring as
alteration products after pyroxene and sericite, epidote and clinozoisite occurring as
alteration products after plagioclase.
4.3.6 Granophyric Gabbro Unit
This unit comprises subhedral plagioclase (50%), subhedral to anhedral pyroxene
(40%) crystals, quartz (5%) and alkali feldspar (5%); augite is the main pyroxene
mineral. Accessory phases include apatite, ilmenite, magnetite (titanomagnetite), biotite
and titanite. Quartz also occurs as aggregates in association with potassium feldspar in
micropegmatite and myrmekitic intergrowths. This unit possesses the greatest degree of
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alteration with amphibole, uralite and chlorite occurring as alteration products after
pyroxene and plagioclase altering to albite, sericite, epidote and clinozoisite; carbonate
occurs as granular aggregates within the groundmass and is likely related to the miarolitic
cavities.
4.4 Mineral Chemistry
With the exception of semi-quantitative electron microprobe studies on platinum-
group minerals (see Section 4.4.5), no quantitative mineral analyses were conducted
during the course of this study. Numerous other authors, including Hriskevich (1968),
Jambor (1971), Card and Pattison (1973), Finn et al. (1982), Conrod (1988, 1989), have
reported mineral chemistries from Nipissing Gabbro intrusions. These data, along with
modal rock compositions, illustrate that most of the rocks in Nipissing Gabbro intrusions
are mafic in composition. Similar compositions for intrusions from the current study are
expected on the basis of similar modal rock compositions.
4.4.1 Olivine
Olivine appears to be extremely rare in Nipissing Gabbro intrusions and where
present is often too altered to obtain a mineral composition. Conrod (1988) reported
chemistry from equant cumulus olivine grains from the Cross Lake intrusion in the
Cobalt area; olivine cores and rims, from the basal quartz diabase, had compositions of
~Fo62 and ~Fo60, respectively. Olivine cores from the orthopyroxene gabbro unit
(hypersthene zone) range upward from ~Fo64 to ~Fo69 and correlate well with nickel
contents in olivine which range from 1430 ppm to 1780 ppm, respectively (Conrod,
1988). Hriskevich (1968), reported olivine compositions (determined optically) from the
Colonial Mine section (Cobalt area) that range from ~Fo70 in the rocks just below the
orthopyroxene gabbro, increasing to a maximum of ~Fo85 in the middle of the
orthopyroxene gabbro, then decreasing to ~Fo70 in the upper part of the orthopyroxene
gabbro unit. Lightfoot et al. (1987) reported slightly enriched Ni compositions for
olivine grains from the Cross Lake intrusion, relative to Ni compositions of olivine with
similar forsterite contents from other mafic intrusions. The relatively high Ni
concentrations of the Cross Lake olivine argues against the significant removal of Ni by a
sulphide phase prior to the crystallization of the olivine in these rocks (Lightfoot et al.,
1987).
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4.4.2 Plagioclase
Plagioclase crystals commonly display Carlsbad and albite twinning with
subordinate pericline and Baveno twinning and normal and oscillatory zoning. Most
authors report an increase in the anorthite content of plagioclase away from the basal
quartz diabase unit, upward into the orthopyroxene gabbro unit, followed by a subtle
decrease through the orthopyroxene gabbro, and a further decrease through the vari-
textured gabbro and granophyric gabbro units (e.g. Lightfoot et al., 1986; Conrod, 1989).
Anorthite contents from plagioclase cores from the Colonial Mine shaft section (Cobalt
area) range from ~An65 in the basal quartz diabase, ~An80 in the orthopyroxene gabbro,
~An70-78 in the vari-textured gabbro and ~An67 in the hangingwall quartz diabase
(Hriskevich, 1968). Anorthite contents from the Portage Bay intrusion (Lake Temagami
area) range from ~An65 in the basal quartz diabase to ~An75 in the orthopyroxene gabbro
(Conrod, 1989).
4.4.3 Pyroxene
Nipissing Gabbro intrusions contain some proportion of orthopyroxene and augite,
with subordinate pigeonite and inverted pigeonite (e.g. Hriskevich, 1968; Dressler, 1979);
Finn et al. (1982) reported normal compositional zoning from Mg-rich cores to Fe-rich
rims in orthopyroxene from the Wanapitei intrusion (Rathbun Lake intrusion). In
general, orthopyroxenes show an increase in Mg-content (enstatite) moving upward and
away from the lower quartz diabase unit and into the lower part of the orthopyroxene
gabbro, followed by a subtle decline in Mg-number (Mg/Mg+Fe) moving up-section
through the orthopyroxene gabbro and finally a decline into and through the vari-textured
gabbro unit (e.g. Hriskevich, 1968; Finn et al., 1982; Naldrett and Lightfoot, 1996). At
the Miller Lake intrusion (Lake Temagami area), orthopyroxene is predominantly
bronzite (cores) and hypersthene (rims) with Mg-numbers from cores ranging 88-61, but
predominantly between 88 and 74; the Mg-number of cores average ~80 (Conrod, 1989).
Clinopyroxene, principally augite, is almost always colourless, is commonly twinned
and in many cases shows herringbone-like exsolution lamellae of orthopyroxene (e.g.
Dressler, 1979). Hriskevich (1968) reported optical composition data for augite crystals
from intrusions in the Cobalt area of Ca42Mg51Fe7 from basal quartz diabase,
Ca38.5Mg49Fe12.5 from pegmatite gabbro, Ca41Mg48Fe11 from vari-textured gabbro, and
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Ca38Mg51Fe11 from olivine-bearing hypersthene gabbro. Jambor (1971) reported
microprobe analyses for zoned clinopyroxene grains from intrusions in the Cobalt-
Gowganda area of 16.4 wt% CaO, 18.9 wt% MgO and 9.9 wt% FeO. Jambor (1971) also
reported compositions for clinopyroxene phenocrysts of 12.9-21.3 wt% CaO, 15.8-19.1
wt% MgO and 7.0-11.9 wt% FeO from basal contact chilled gabbro and 18.7-20.2 wt%
CaO, 15.5-16.8 wt% MgO and 6.6-6.7 wt% FeO from upper contact chilled gabbro.
4.4.4 Sulphides
Disseminated and blebby magmatic sulphides are the two most common primary
textures (Photo 4-17), with subordinate interstitial and net-textured sulphides.
Accumulations of significant sulphide are not as common but span the range from semi-
massive (25 to 70% total sulphide) to massive (>70% total sulphide), as observed at the
Rastall occurrence in Janes Township (Chiniguchi River intrusion). Commonly, primary
magmatic textures are absent, with sulphides replacing primary silicate minerals
(metasomatic) along margins and cleavage planes and occurring as irregularly shaped
granular dispersions enclosed by silicate grains, and as secondary veining (fracture
filling). Sulphide minerals, although highly dependent on the specific mineralizing
environment (i.e. hydrothermal versus magmatic), in order of decreasing abundance
include pyrrhotite, chalcopyrite, pentlandite and pyrite; millerite was reported by Rowell
and Edgar (1986) from the Rathbun Lake occurrence.
4.4.5 Platinum-Group Minerals
Very little work has been published on the composition of platinum-group minerals
(PGM) in Nipissing Gabbro suite intrusions. In this study, semi-quantitative electron
microprobe analyses, carried out at The University of Western Ontario, London,
identified discrete PGM in sulphide-bearing rocks from the Chiniguchi River intrusion
(Janes Township) with compositions that comprise Pd-Bi-Te, Pd-Bi-Sb-(As?)-Te and Pt-
As (likely sperrylite). The PGM, which are associated with both the silicates and
sulphides (chalcopyrite, pyrrhotite and pentlandite), measure from 10 to 25 µm and are
depicted in back-scattered electron (BSE) images in Photo 4-18.
Rowell and Edgar (1986), using semi-quantitative electron microprobe analyses,
determined compositions of 45 PGM grains from the Rathbun Lake occurrence,
Wanapitei Lake intrusion (Fig. 1-2).
86
Photo 4-17. Photomicrographs showing magmatic disseminated (ds) and blebby (bs) sulphide mineralization, the two most common forms of sulphide in mineralized orthopyroxene gabbro. (A) and (B) Blebs (primary) of chalcopyrite (cp) and pyrrhotite (po) with disseminated (remobilized) chalcopyrite throughout the groundmass of amphibole (amp) and chlorite (chl) after pyroxene (pyx). Larger amphibole crystals are pseudomorphs after pyroxene phenocrysts. Both photos were taken using a combination of plane and reflected light. Field of view is 8 mm wide for both photographs.
87
Photo 4-18. BSE images of discrete platinum-group minerals in sulphide-bearing rocks from the Chiniguchi River Intrusion, Janes Township; semi-quantitative analysis showed compositions that included Pd-Bi-Te, Pd-Bi-Sb-(As?)-Te, and Pt-As. The dark area comprises gangue silicate minerals. (A) Grains of Pd-Bi-Te occurring on rims of pentlandite (pn) in sample JB97-109. (B) A single grain of Pd-Bi-Sb-Te associated with pyrrhotite (po) and chalcopyrite (cp) in sample JB97-87C.
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Identified PGM included merenskyite (Pd-Bi-Sb-Te), kotulskite (Pd-Bi-Sb-Pt-Te),
temagamite (Pd-Sb-Bi-Te), michenerite (Pd-Bi-Pt-Sb-Te) and sperrylite (Pt-As).
Optically, Rowell and Edgar (1986) identified 70% of the 45 PGM grains as merenskyite,
20% as kotulskite and 5% as michenerite and 5% as temagamite. The majority of grain
size diameters ranged from 1 to 20 µm for merenskyite, <1 to 40 µm for kotulskite, 65-80
µm for michenerite and <20 µm diameter for temagamite; a single sperrylite grain, the
only grain of sperrylite that was identified, had a diameter of 250 µm. Rowell and Edgar
(1986) reported that 64% of the Pd minerals occurred in the gangue, often as clusters of
up to 40 grains, with the remaining 35% of Pd minerals associated with sulphides - 18%
at chalcopyrite-silicate interfaces, 7% as inclusions in chalcopyrite and 11% as inclusions
in pyrite. On the basis of the PGM mineralization, dominated by Pd bismuthotellurides,
and whole-rock PGE geochemistry, Rowell and Edgar (1986) proposed a hydrothermal
origin for the mineralization at the Rathbun Lake occurrence.
4.5 General Geochemistry
Geochemical characteristics of Nipissing Gabbro intrusions have been described by
several authors including Jambor (1971), Card and Pattison (1973), Conrod (1989),
Rowell and Edgar (1986) and Lightfoot and Naldrett (1996). Rocks from the intrusions
are dominantly tholeiitic and sub-alkaline, with evolved rock types and differentiated
intrusions trending toward calc-alkaline affinities (Lightfoot and Naldrett, 1996).
Lightfoot and Naldrett (1989), Lightfoot et al. (1993), and Lightfoot and Naldrett (1996),
in their review of 100 samples (chilled quartz gabbro and least differentiated gabbro)
collected from 15 different Nipissing Gabbro intrusions, proposed that the parental
magma to the Nipissing Gabbro suite was relatively uniform in composition and
characterised by elevated SiO2 (50.0-51.5 wt%), moderate MgO (8-9 wt%), strong light
rare-earth element (LREE) and large ion lithophile element (LILE) enrichment (La/Sm =
2.5-3.5; Th/Nb = 0.7-0.9), epsilon NdCHUR of -2.7 to -5.9 and low 143Nd/144Nd (indicating
enriched mantle or crustal source), and conspicuous negative Nb, Ta, P and Ti anomalies
(relative to LILE and LREE), suggesting crustal interaction and/or contamination. On the
basis of these geochemical characteristics and the outcrop patterns of Nipissing Gabbro,
Lightfoot et al. (1986, 1987) and Lightfoot and Naldrett (1996) surmised that Nipissing
Gabbro represent the intrusive portion of an eroded continental flood basalt, where
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magmas cut through Archaean basement rocks and Huronian Supergroup sedimentary
rocks as dikes, and spread laterally through the Huronian lithologies as sills.
4.5.1 Emplacement Model for Nipissing Gabbro
Lightfoot et al. (1987) and others (e.g. Conrod (1988, 1989); Lightfoot et al., 1993)
have suggested that the calc-alkalic characteristics are the result of pre-emplacement
enrichment of LILE (Cs, Rb, Ba, and Sr) due to interaction with a recycled, Archaean
crustal component , or continental crustal contamination as the magmas evolved in deep
crustal reservoirs (i.e. staging chambers). Lightfoot et al. (1993) surmised that the
parental magmas differentiated at depth, precipitating olivine which is conspicuously
absent from almost all intrusions, and were then subsequently emplaced as uniform low-
Mg magmas, acquiring their LREE enrichment signature from continental crust, perhaps
during migration from the mantle to the surface (e.g. Lightfoot et al., 1993). This
scenario is consistent with the tectonic setting presented in Figure 3-3. In considering the
homogenous nature of the parental magma and the large volume of assimilated crustal
material (>20%) that would be required to produce the observed REE and trace element
signatures, Lightfoot et al. (1993) suggested that the source characteristics of the magmas
may have been acquired as a result of subduction events relating to the earlier Archaean
Kenoran Orogeny. Tomlinson (1996) and Tomlinson et al. (1999) arrived at similar
conclusions for magmas to Early Huronian volcanic rocks of the Elliot Group, suggesting
that the principal magma source inherited its geochemical signature from
metasomatically-enriched upper mantle, which was geochemically modified as a result of
subduction-accretionary events associated with the Kenoran Orogeny.
Work by several authors, including Lightfoot et al. (1987), Conrod (1989) and
Lightfoot and Naldrett (1989), suggests that petrological variations within the intrusions
are largely controlled by the coupling of post-emplacement fractionation and assimilation
processes or assimilation-fractional crystallization (AFC). Lightfoot and Naldrett (1989),
in applying the AFC model to the Kerns sill (Lake Temagami area), determined that
assimilation and fractionation worked in concert to produce a signature whereby the least
fractionated samples are the least contaminated and the most fractionated samples,
(characterized by low Mg-number, Ni and Cr and by high incompatible element
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concentrations), show the largest amount of contamination (characterized by higher
Th/Zr, La/Zr and U/Zr and lower 143Nd/144Nd).
Figure 4-3. Model for the evolution of a Nipissing Gabbro sill through the process of assimilation-fractional crystallization (AFC). Stage 1: Intrusion of laminar to moderately turbulent parental magma into Huronian Supergroup sedimentary rocks and crystallization of chilled margin gabbro along the upper and lower contacts of the sill; Stage 2: Erosion of roof rocks by hot magma, mainly within the arches of the undulatory sills, and crystallization/accumulation of lowermost orthopyroxene gabbro unit, accompanied by precipitation of disseminated sulphide. A double-diffusive interface (DDI) develops between the underlying mafic magma and overlying hybrid aplitic magma; Stage 3: Crystallization of gabbro-leucogabbro and vari-textured gabbro units overlying the orthopyroxene unit, decline in the rate of assimilation of roof rocks and progressive breakdown of the double-diffusive interface as the aplitic magma solidifies (aplite pods and dykes); Stage 4: Complete crystallization of the upper portions of the vari-textured gabbro and breakdown of the double-diffusive interface resulting in the mixing of the remaining aplitic and mafic magmas and crystallization of granophyric rocks. This model is based on observations and geochemical data from the Kerns sill, Lake Temagami area (after Lightfoot and Naldrett, 1989).
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Figure 4-4a. Model for the development of undulatory Nipissing Gabbro intrusions (after Lightfoot and Naldrett, 1996 and Conrod, 1989). Stage 1: Development of auxiliary magma chamber within deeper Archaean crust; crystallization and gravitative settling of olivine ± pyroxene into olivine dominated cumulates; S-saturation of initially S-undersaturated magma through crustal contamination; crystallization and accumulation of Ni-Cu dominated sulphides. Stage 2: Initial displaced magma pulse, comprising moderate to high MgO magmas with abundant orthopyroxene phenocrysts, results in development of undulatory Nipissing Gabbro sill within Huronian Supergroup sequences; possibility for subsequent S-undersaturated magma pulses and resorption of earlier crystallized olivine ± pyroxene and sulphides.
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Figure 4-4b. Model for the development of undulatory Nipissing Gabbro intrusions (after Lightfoot and Naldrett, 1996 and Conrod, 1989). Stage 3: Crystallization of magmas in inflating Nipissing Gabbro sill, accompanied by differentiation, assimilation, and accumulation of orthopyroxene ±sulphide in lower orthopyroxene gabbro units; and, Stage 4: Relaxation and differentiation within Nipissing Gabbro sill; fractionated and contaminated rocks become concentrated within arches and the most primitive rocks (±sulphides) are concentrated in limbs and basins, resulting in the current type-stratigraphy (Fig. 4-2).
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Their model, also used by Conrod (1989), suggested that early crystallization is
accompanied by little or no contamination (chilled diabase; basal quartz diabase;
hypersthene diabase), followed by moderate contamination (vari-textured diabase), and
finally by substantial contamination (granophyric diabase) in the upper portions of the
sills, accompanied by the assimilation of hangingwall sedimentary rocks and the
formation of aplitic rocks. Schematic representations of the AFC processes as they relate
to Nipissing Gabbro intrusions are shown in Figures 4-3 and 4-4.
4.6 Mineralization
It has long been recognised that the region between Sault Ste. Marie and Cobalt
contains hundreds of Cu-Ni sulphide (and other metals) occurrences that are associated
with intrusive rocks of the Nipissing Gabbro and the East Bull Lake suite, and to a lesser
extent Huronian Supergroup sedimentary rocks (Card and Pattison, 1973). On the basis
of current field observations and earlier work by Card and Pattison (1973), it is noted that
mineralization in Nipissing Gabbro intrusions varies in type and style across the Southern
Province (Fig. 4-5). Quartz-carbonate vein associated Co-Ag-(PGE-Ni) sulphides and
sulpharsenides dominating in the northeast (Cobalt area); predominantly contact related
Cu-Ni-Co-(PGE) are most conspicuous in the region immediately southwest of Cobalt
(Lake Temagami area); intrusion-hosted Ni-Cu-PGE-(Au) sulphides occur in the regions
immediately northeast, south and west-southwest of the City of Greater Sudbury; contact-
related and intrusion-hosted Ni-Cu-Co-PGE sulphides are common in the areas southwest
of Sudbury (most common but not restricted to the area south of the Murray Fault Zone)
and in the Elliot Lake area; and, secondary (late) quartz-carbonate vein associated Cu
sulphides are most common in Nipissing Gabbro intrusions between Blind River and
Sault Ste. Marie. Lightfoot et al. (1987) noted that this variation in type and style of
mineralization appeared unrelated to differences in lithology, degree of metamorphism,
or level of intrusion of the Nipissing Gabbro. Sulphide occurrences from Nipissing
Gabbro in the current study area have been described as magmatic by Lightfoot et al.
(1986, 1987) and Lightfoot et al. (1993), and as hydrothermal by Finn et al. (1982) and
Rowell and Edgar (1986).
PGE-associated sulphide mineralization is dominated by chalcopyrite and pyrrhotite
with subordinate pentlandite and pyrite (James et al., 2002b). The mineralization occurs
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as three main types, viz.: (1) disseminated sulphide mineralization with the most
consistent and persistent PGE contents (i.e. 500-6000 ppb PGE) and moderate base metal
concentrations (i.e. ~0.75-1.0% Cu+Ni); (2) contact-associated, disseminated to semi-
massive sulphide mineralization with very high PGE (i.e. 8,000-123,000 ppb PGE) and
base metal contents (i.e. 1.5-3.0% Cu+Ni); and, (3) massive sulphide mineralization with
typically low PGE (i.e. <250 ppb PGE) and high base metal content (>3% Cu+Ni). Pd:Pt
ratios in mineralized samples are about 5:1, and in non- or poorly mineralized samples
are about 2.5:1; very high PGE concentrations (i.e. >7000 ppb) tend to have high Pd:Pt
ratios (i.e. >10:1); Cu:Ni ratios are commonly 2:1 but may be as high as 40:1 in
remobilized sulphide. Background concentrations of PGE, Au, Cu and Ni are estimated
to have maximum values ~40 ppb Pd, 32 ppb Pt, 9 ppb Au, 94 ppm Cu, and 376 ppm Ni;
these arithmetic averages are based on the analysis of 23 non-mineralized (low-S and
<100 ppm Cu) samples (James et al., 2002b).
Much of the known and potentially economic PGE sulphide mineralization occurs
within the lower to middle parts of the orthopyroxene gabbro unit (e.g. Lightfoot and
Naldrett, 1996; James et al., 2002b), and is generally located within the lower one-third
of the stratigraphy (Figs. 4-1 and 4-2). This style, indicated by type-1 (above), is best
described as stratabound and more precisely as stratiform, and for the most part consists
of 1-5% fine- to medium-grained disseminated and blebby (up to 7 cm diameter)
chalcopyrite, pyrrhotite and pentlandite, with subordinate net-textured sulphide. Blebby
sulphide commonly show segregation textures (Photo 4-19) of pyrrhotite and
chalcopyrite either as blebs with pyrrhotite cores rimmed by chalcopyrite or as blebs with
half pyrrhotite and half chalcopyrite; Lightfoot and Naldrett (1996) reported similar
sulphide segregation textures, referring to the blebby sulphide as globules. This style
(type-1) of mineralization appears to hold the most promise for large-tonnage, moderate-
grade open cast mining. Semi-massive (25-80% total sulphide) and massive (>80% total
sulphide) sulphide is rare, but where observed occurs at or near the basal contact of the
intrusion, toward the base of the orthopyroxene gabbro unit, or within the basal gabbro-
sediment breccia (James et al., 2002b).
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96
Photo 4-19. Orthopyroxene gabbro with disseminated and blebby sulphide from the Bassoon Lake Intrusion, Dieppe Township. (A) Coarse sulphide bleb showing segregation of chalcopyrite (cp) and pyrrhotite (po). A centimetre ruler is provided for scale. (B) Disseminated and blebby sulphide showing segregation textures (chalcopyrite and pyrrhotite) in the coarser blebs. An irregular patch of blue-grey cherty quartz (qtz) is also identified. The Canadian one dollar coin is about 2.5 cm in diameter.
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Lightfoot et al. (1987), in assuming the chilled margin samples represent parental
magma compositions, suggested that the uniform composition of the parental magma
indicated limited contamination of the magma en route through the crust or through the
assimilation of local country rocks. This implies that magmatic sulphide segregation was
not triggered by crustal contamination from local country rocks but rather from large-
scale, homogeneous contamination. It is therefore likely that the dominant control on
PGE-bearing sulphide mineralization is that of in-situ normal fractional crystallization
within individual bodies, with PGE-rich sulphide precipitation accompanied by
orthopyroxene ± olivine crystallization in the lower orthopyroxene gabbro unit.
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CHAPTER 5: CONSIDERED NIPISSING GABBRO INTRUSIONS
5.1 Introduction and Overview
Over the past six years, exploration for sulphide-associated PGE in Nipissing Gabbro
intrusions has dramatically increased the geochemical database and current understanding
of sulphide mineralization occurring in these intrusions. Of particular note are the
intrusions located within about 100 km of the City of Greater Sudbury (Fig. 1-2),
specifically those located northeast of Sudbury. These include the Kukagami Lake
(Kelly Township), Chiniguchi River (Janes Township), Sargesson Lake (Janes
Township), and Rathbun Lake (Rathbun Township) intrusions, and those located west
and southwest of Sudbury, including the Charlton Lake-Casson Lake (Curtin Township),
Nairn (Nairn Township), Bell Lake (Lorne), Bassoon Lake (Dieppe Township), Louie
Lake (Louise Township), and Makada Lake (Waters Township) intrusions. Other
intrusions which have been the subject of recent exploration activities include the
O’Brien-Big Swan (Dunlop-Porter townships; Card and Palonen, 1976) and the
Shakespeare (Shakespeare Township; Card and Palonen, 1976) intrusions (Fig. 1-2).
Recent diamond drilling programs have been completed by Pacific North West
Capital Corp. and their exploration partner Anglo American Platinum Corporation
Limited on several sulphide occurrences hosted by Nipissing Gabbro intrusions,
including the Jackie Rastall occurrence (3.1 g/t PGE, 1.1% Cu and 0.3% Ni over 15.0
metres), located in the Chiniguchi River intrusion, the Washagami occurrence (3.9 g/t
PGE, 0.44% Cu and 0.30% Ni over 4.4 metres), located in the eastern part of the
Kukagami Lake intrusion, and the Sargesson Lake occurrence (1.34 g/t PGE, 0.19% Cu
and 0.13% Ni over 1.2 metres), located in the Sargesson Lake intrusion, about 3.5 km
east of the Chiniguchi River intrusion (Fig. 5-1). To date, only one deposit of potentially
economic PGE-Cu-Ni sulphide mineralization has been delineated in the Nipissing
Gabbro suite. This is the Shakespeare Deposit (Fig. 1-2), which has an Indicated
Resource, from two deposits, of ~12.0 million tonnes grading 0.35% Ni, 0.36% Cu,
0.02% Co, 0.19 g/t Au, 0.34 g/t Pt, and 0.38 g/t Pd (Ursa Major Minerals Incorporated,
Press Release 15/04/04).
In this chapter, detailed data from individual Nipissing Gabbro intrusions is
presented using various geochemical diagrams and chemostratigraphic plots. In these
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diagrams and plots, the rock sample name, which is mainly based on field classification,
is used as the principal label, with the CIPW normative rock name provided in
parentheses. For example, a label of “quartz gabbro (G)” refers to a field name of “quartz
gabbro” and a CIPW normative classification of gabbro is referenced using “G”.
5.2 General Geochemistry
The locations for Nipissing Gabbro intrusions from which 188 rock samples and 69
drill core samples were collected are shown in Figure 1-2; a summary of the sample
locations is provided in Table 5-1. The 188 samples were collected from what are
considered to be, based on the most current geological mapping (i.e. Ontario Geological
Survey, 1977, 1979), seventeen different Nipissing Gabbro intrusions and their average
geochemical characteristics are summarized in Table 5-2. The data set of 188 samples
includes samples collected from the seven lithogeochemical traverses and the detailed
geochemical sampling sites. Details of the geochemical characteristics of individual
intrusions and the drill core samples are considered separate from the suite of 188
Nipissing Gabbro samples. A detailed listing of Nipissing Gabbro sample data and
descriptions are provided in Appendix 1, petrographic descriptions of the 104 thin
sections are provided in Appendix 2, and diamond drill hole data and logs are provided in
Appendix 3.
CIPW normative calculations were completed on 152 samples (all with <1 wt% S)
and a select number of these are provided in Table 5-3 with a complete listing provided in
Appendix 1; rock types were determined on the basis of the weight percent normative
minerals. Excluding the two samples of aplite, the majority of samples (111) are silica-
oversaturated, quartz-hypersthene-normative and mainly classify as gabbro with
subordinate leucogabbro. Excluding the seven samples of chilled margin, 28 of the
samples are silica-saturated, hypersthene-olivine-normative and mainly classify as
gabbronorite with subordinate leucogabbronorite, melagabbronorite, olivine
leucogabbronorite, leucogabbro and olivine gabbronorite. The seven samples of chilled
margin are silica-oversaturated, quartz-hypersthene-normative and classify as gabbro.
Two samples (JB97-78A and JB97-93) are silica-saturated, hypersthene-olivine-
corundum-normative and classify as olivine gabbronorite and olivine leucogabbronorite.
100 100
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Area *Property Centre Township Intrusion Code UTM-mE UTM-mN 1W 314386 5139916 Bridgland/Kirkwood/Wells Basswood Lake 2W 319567 5144030 Wells Appleby Lake 3E 554964 5186759 Clement Manitou Lake
4SW 454324 5110831 Curtin Casson Lake (AN3) 5SW 445114 5110204 Curtin Charlton Lake 6NW 450091 5162093 Ermatinger Fox Lake - Outlier 7SW 448725 5122694 Foster Brazil Lake 8E 547360 5171329 Janes Chiniguchi River 9E 551544 5170842 Janes Sargesson lake
10E 536345 5177849 Kelly Kukagami Lake 11E 542511 5173632 Kelly Washagami Lake
12SW 457443 5132222 Lorne Bell Lake 13C 470213 5129272 Louise Louie Lake
14NW 455207 5175760 Moncrieff Geneva Lake - Outlier 15W 439524 5138247 Porter Big Swan 16E 528537 5170552 Scadding Scadding 17C 489666 5136654 Waters Makada Lake
18SW 454323 5129509 Nairn Nairn 19E 526193 5178855 Rathbun Rathbun Lake
Table 5-1. Summary of sample locations in Nipissing Gabbro intrusions in the area Sault
Ste. Marie and Lake Temagami. The approximate centre coordinates of each property are
in NAD83, Zone 17. Area codes are assigned to each of the intrusions/sampling areas for
plotting and reference purposes.
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Area <0.05 wt% S <1 wt% S All Code 59 samples 152 samples 188 samples 1W 6 15 16 2W - 12 12 3E 1 9 9
4SW 4 4 5 5SW 4 10 10 6NW - 1 1 7SW 1 4 5 8E 6 21 34 9E - 1 1 10E 9 23 25 11E 3 7 7
12SW 6 6 6 13C 1 8 15
14NW - 1 1 15W - 1 1 16E 1 3 3 17C 16 26 30
18SW 1 - 6 19E - - 1
Table 5-1 (cont). Summary of sample locations in Nipissing Gabbro intrusions in the area
Sault Ste. Marie and Lake Temagami. The approximate centre coordinates of each
property are in NAD83, Zone 17.
103
Area Intrusion S Se S/Se Ni Ir Ru Rh Pt AreaCode wt% ppb - ppm ppb ppb ppb ppb Code1W Basswood Lake AVG: 0.32 821 3859 71 0.24 1.92 1.56 11.28 1W
MED: 0.06 279 2029 60 0.24 0.24 0.43 10.01N: 16 16 16 16 2 7 7 8
2W Appleby Lake AVG: 0.16 458 3564 83 0.59 0.27 5.71 2WMED: 0.09 370 2300 88 0.59 0.21 5.00
N: 12 12 12 12 1 3 53E Manitou Lake AVG: 0.06 255 2226 99 5.00 2.77 2.40 2.11 3E
MED: 0.06 290 2069 110 5.00 2.77 2.40 2.32N: 9 9 9 9 2 1 2 5
4SW Casson Lake AVG: 0.51 1516 3382 428 0.29 0.59 1.61 69.15 4SWMED: 0.04 314 1401 172 0.12 0.27 0.86 21.50
N: 5 5 5 5 5 4 5 55SW Charlton Lake AVG: 0.09 485 1946 169 0.17 0.33 0.53 9.91 5SW
MED: 0.07 303 2413 135 0.17 0.30 0.32 2.47N: 10 10 10 10 2 8 7 10
6NW Fox Lake N=1 0.05 270 1852 78 6NW7SW Brazil Lake AVG: 6.80 11990 5675 1343 0.20 7SW
MED: 0.07 300 2333 89 0.20N: 5 5 5 5 2
8E Chiniguchi River AVG: 1.04 5900 1767 1615 0.73 3.64 105.86 199.94 8EMED: 0.26 1699 1504 434 0.23 3.77 0.75 35.11
N: 34 34 34 34 14 5 17 299E Sargesson lake N=1 0.77 5683 1355 1116 0.26 0.38 1.01 101.00 9E
10E Kukagami Lake AVG: 0.19 760 2526 341 0.26 0.18 2.21 47.54 10EMED: 0.05 229 2314 134 0.13 0.15 0.40 10.59
N: 25 24 24 25 11 7 19 2111E Washagami Lake AVG: 0.05 333 1544 164 0.20 0.89 18.24 11E
MED: 0.05 321 1558 160 0.18 0.88 17.83N: 7 7 7 7 5 5 7
12SW Bell Lake AVG: 0.01 45 1716 301 0.93 1.94 1.83 10.88 12SWMED: 0.01 38 1316 313 1.10 2.16 1.72 11.92
N: 6 6 6 6 6 6 6 613C Louie Lake AVG: 7.14 3485 20490 1044 0.86 1.99 2.45 27.22 13C
MED: 0.13 319 3918 188 0.51 1.60 1.76 10.83N: 15 15 15 15 9 9 10 15
14NW Geneva Lake N=1 0.14 428 3271 44 0.48 0.00 14NW15W Big Swan N=1 0.16 348 4598 45 9.07 15W16E Scadding AVG: 0.05 433 1254 110 0.23 0.50 12.50 16E
MED: 0.05 400 1325 114 0.20 0.50 12.50N: 3 3 3 3 3 1 2
17C Makada Lake AVG: 1.90 335 56720 664 0.56 1.38 1.20 7.35 17CMED: 0.02 85 2485 211 0.46 1.25 0.88 6.30
N: 30 30 30 30 17 19 23 2518SW Nairn AVG: 7.10 9409 7541 5360 7.65 16.38 14.14 62.64 18SW
MED: 8.09 1671 48399 5333 3.02 6.55 3.78 32.25N: 6 6 6 6 5 5 6 6
19E Rathbun Lake N=1 10.50 88425 1187 9367 0.33 7.80 3961.00 19E Table 5-2. Summary of geochemical characteristics, Nipissing Gabbro intrusions.
104
Intrusion Pd Au Cu Pd/Pt Cu/Ni MgO Mg#ppb ppb ppm - - wt%
Basswood Lake 7.60 4.93 436 0.67 6.18 4.73 451.83 4.25 148 0.18 2.46 4.66 4311 16 16 8 16 16 16
Appleby Lake 5.18 16.51 154 0.91 1.87 5.25 462.75 3.61 170 0.55 1.94 5.74 50
6 11 12 3 12 12 12Manitou Lake 3.31 3.27 128 1.57 1.29 6.45 56
2.89 3.15 150 1.24 1.36 6.75 596 7 9 5 9 9
Casson Lake 109.21 39.23 661 1.58 1.55 10.99 7446.50 5.50 108 2.16 0.63 10.92 75
5 5 5 5 5 5Charlton Lake 23.87 6.69 257 2.41 1.52 9.06 69
2.42 2.46 158 0.98 1.17 9.39 6910 10 10 10 10 10 10
Fox Lake 1.93 0.00 170 2.18 5.79 51Brazil Lake 63.65 4.54 132 0.10 7.16 62
63.65 2.20 130 1.46 7.30 632 4 5 5 4
Chiniguchi River 1180.61 145.22 3724 5.90 2.31 8.55 6456.00 21.03 1130 1.59 2.60 8.43 65
32 33 34 29 34 33 33Sargesson lake 116.60 157.30 3217 1.15 2.88 8.99 66Kukagami Lake 169.29 14.07 563 3.56 1.65 8.88 67
11.06 2.88 112 1.04 0.84 8.82 6722 21 25 21 25 25 25
Washagami Lake 58.39 7.05 163 3.20 0.99 8.75 6957.41 4.81 160 3.22 1.00 8.57 68
7 7 7 7 7 7Bell Lake 5.45 1.03 30 0.50 0.10 15.91 79
6.29 0.91 32 0.53 0.10 16.52 796 6 6 6 6 6
Louie Lake 46.93 14.31 448 1.72 0.43 9.45 5513.65 6.37 312 1.26 1.66 10.51 73
15 15 15 15 15 13 13Geneva Lake 0.00 6.67 190 4.32 3.45 31
Big Swan 9.12 26.80 75 1.01 1.67 5.71 53Scadding 7.33 1.93 118 0.59 1.08 7.61 60
5.00 2.10 107 0.40 0.94 8.10 643 3 3 2 3 3
Makada Lake 8.42 22.34 204 1.15 0.31 9.61 646.36 1.82 72 1.01 0.34 9.72 7027 27 30 25 30 30 30
Nairn 50.22 30.61 6353 0.80 1.19 11.35 5837.31 23.75 962 1.16 0.18 11.35 58
6 6 6 6 6 2Rathbun Lake 6230.00 941.00 377129 1.57 40.26 4.23 32
9
5
4
7
6
3
2
Table 5-2 (cont). Summary of geochemical characteristics, Nipissing Gabbro intrusions.
105
Sample JB97-48 JB98-148 RK-2 JB97-19A JB98-121A JB97-87G 44769 44725Township Wells Lorne Waters Kelly Wells Janes Janes Janes
Field Name CM G G qtzG vtG G OPXG GCIPW Name G LGN OGN G LG G GN OLGNNormatives Q-H H-O H-O Q-H Q-H Q-H H-O H-ONorm Class so ss ss so so so ss ss
Norm Mineralsquartz 2.60 2.64 9.27 8.98
plagioclase 44.09 19.87 43.36 43.04 44.87 38.43 48.3 47.84orthoclase 5.91 0.83 5.73 1.71 10.28 3.07 3.84 5.91Nephelinecorundumdiopside 19.77 34.97 21.71 23.20 3.49 15.12 25.56 8.44
hypersthene 22.79 35.28 16.75 26.28 25.48 27.07 11.83 6.96olivine 6.41 9.59 7.03 27.1ilmenite 1.73 0.51 0.55 0.82 3.02 0.87 0.68 0.99
magnetite 2.58 2.12 1.83 1.93 3.04 2.58 1.65 2.17apatite 0.07 0.05 0.07 0.02 0.44 0.16 0.07 0.09zircon 0.03
chromite 0.01pyrite 0.13 0.02 0.02 0.08 0.11 3.99 1.1 0.51calcite 0.36 0.43 0.32
Na2CO3
*Total: 100.03 100.06 100.04 100.04 100.03 100.28 100.06 100.01
Table 5-3. Summary of CIPW normative calculations on 8 rock samples with <1 wt% S.
Rock types are determined on the basis of weight percent normative minerals.
*normalized to 100%; CIPW rock names based on weight % normative minerals
CM=chilled margin; G=gabbro; qtzG=quartz gabbro; OPXG=orthopyroxene gabbro;
OGN=olivine gabbronorite; GN=gabbronorite; OLGN=olivine leucogabbronorite;
LG=leucogabbro; LGN=leucogabbronorite; Normatives: Q=quartz; N=nepheline;
H=hypersthene; O=olivine; C=corundum; Norm Class: su=silica-undersaturated (alkali
basalt); ss=silica-saturated (olivine tholeiites); so=silica-oversaturated (quartz tholeiites).
106
Sample JB97-78A (see Appendix 1), from Waters Township, is described as a sheared
gabbro, containing about 5% disseminated sulphide associated with blue-grey quartz
eyes. Sample JB97-93 (Big Swan, Porter Township; see Appendix 1) is described as a
sheared gabbro, containing disseminated pyrite-arsenopyrite and is proximal to a shear
zone that cuts through the Nipissing Gabbro body. One sample (JB97-54A; see
Appendix 1) is silica-oversaturated, quartz-hypersthene-corundum-normative, classifying
as a leucogabbro. This sample, collected from the Appleby Lake intrusion (Wells
Township), is strongly altered, granophyric gabbro, that occurs proximal to sulphide-
bearing quartz-carbonate veining. One sample (JB97-32; see Appendix 1) is silica-
undersaturated, nepheline-olivine-normative, classifying as an olivine leucogabbronorite.
This sample, collected from Clement Township, is described as a relatively fresh,
massive, medium-grained gabbro.
It is important to note that the lithogeochemical studies reported by Conrod (1988),
Lightfoot and Naldrett (1989), and Lightfoot et al. (1987, 1986, 1991a) have shown wide
compositional ranges within individual units from the intrusions they studied. Wide
compositional variations were also noted from individual intrusions in the current study.
These authors attributed these compositional variances to be reflective of a process
involving strong in-situ differentiation and contamination. Conrod (1988) and Lightfoot
and Naldrett (1996) presented an Assimilation-Fractional Crystallization (AFC) model to
explain many of the wide ranges in composition within individual intrusions (see
previous discussion and Fig. 4-5).
5.2.1 Major Element Variations
Samples with elevated S (>1 wt% S) concentrations are not included in these plots as
high sulphur concentrations skew the major element chemistry in favour of Fe; a further 8
samples have no major element data and so are also removed from the data set. The
majority of Nipissing Gabbro samples plot within the tholeiitic field (Irvine and Baragar,
1971) on the AFM diagram (Fig. 5-2) and classify as sub-alkaline on the basis of the SiO2
versus Na2O+K2O discrimination diagram of Miyashiro (1978). With a few exceptions,
the Nipissing Gabbro sample suite exhibits a strong negative correlation between TiO2
and Mg-number (Fig. 5-3); as TiO2 increases and Mg-number decreases with
107
fractionation. The wide range in values indicate that the Nipissing Gabbro magmas
underwent a considerable amount of in-situ fractionation.
Figure 5-2. AFM diagram showing the major element features of Nipissing Gabbro rocks
from intrusions in the Sudbury region. The majority of lithologies plot along the
tholeiitic trend of Irvine and Baragar (1971); a few samples plot within the calc-alkaline
region. The two samples that plot closest to the Na2O+K2O apex (JB97-65 and JB97-
78B) are aplite dikes.
108
Geochemical characteristics of the samples suite include 45.86-77.93 wt% SiO2 (median
= 51.3 wt% SiO2), 0.14-3.54 wt% TiO2 (median = 0.52 wt% TiO2), 0.13-19.41 wt% MgO
(median = 8.4 wt% MgO), and 22-83 Mg-number (median = 66 Mg-number). Samples
of aplite dike have highest SiO2 (70.6 and 77.9 wt% SiO2) and lowest MgO (0.13-1.11
wt% MgO). Seven samples of chilled margin (quartz gabbro and gabbro/diabase) are
characterized by 49.8-51.9 wt% SiO2 (average = 50.0 wt% SiO2), 0.52-0.89 wt% TiO2
(average = 0.69 wt% TiO2), 6.13-8.43 wt% MgO (average = 7.73 wt% MgO), and 52-66
Mg-number (average = 61 Mg number).
5.2.2 Trace and Rare-Earth Element Variations
Two subsets of the 188 samples of Nipissing Gabbro were generated. The first
(Group-1) is sorted on the basis of location (intrusion/Township) and the second (Group-
2) is sorted on the basis of CIPW normative rock type. Primitive mantle-normalized
multi-element diagrams for Group-1 and Group-2 data are shown in Figures 5-4 and 5-5,
respectively. A summary of the important REE features of these Nipissing Gabbro
samples are provided in Table 5-4. In general, Nipissing Gabbro show strong LILE
enrichment (~10-100 times primitive mantle), moderate LREE enrichment (La/Sm ~1.0-
4.4; average ~2.3), and low to moderate HREE enrichment (~1-10 times primitive
mantle). Most of the Nipissing Gabbro samples display subtle to pronounced negative
Nb+Ta, P* (calculated using P* = P2O5 x 0.43646) and Ti* (calculated using Ti* = TiO2
x 0.59950) anomalies. The average chilled margin pattern is similar and parallel to the
Group-1 and Group-2 data (Figs. 5-5 and 5-6). Patterns for individual chilled margin
samples plot very close together and are consistent between profiles, characterized by
pronounced negative Nb+Ta and P* anomalies and weakly negative Ti* anomalies.
These negative HFSE anomalies (Nb, Ta and Ti*), along with LREE enrichment patterns
and relatively restricted La/Sm ratios are characteristics of enriched mantle magmas
which became contaminated with crustal material during and post-emplacement (Conrod,
1988) and/or within a crustal reservoir (i.e. auxiliary chamber) prior to emplacement
(Lightfoot et al., 1993); continental flood basalts share similar geochemical signatures
(Arndt et al., 1998).
In Figure 5-7, data from 150 Nipissing Gabbro rocks (unmineralized and
mineralized) are plotted using primitive mantle-normalized (Th/Yb)N and (Nb/Th)N,
109
which is useful for modelling the effects of crustal contamination on the composition of a
proposed or known primary melt (e.g. Lesher et al., 2001) and for determining parental
magma sources.
0.1
1.0
10.0
0102030405060708090
Mg-number
TiO
2 (w
t%)
1W2W3E4SW5SW6NW7SW8E9E10E11E12SW13C14NW15W16E17CChilled Margin Avg
fractionation
(152 samples)
Figure 5-3. Variation in Mg-number versus TiO2, showing the relative compositions and
fractionation trends of Nipissing Gabbro samples, sorted by area. Value for average
chilled margin gabbro is from the current study.
110
Intrusion N ∑REE (La/Sm)N (Th/Nb)N Eu/Eu* (La/Yb)CN (La/Sm)CN
Basswood Lake 16 95 2.38 6.59 0.84 4.02 2.35Appleby Lake 12 116 4.16 5.39 0.78 10.11 4.10Manitou Lake 9 59 2.03 2.98 1.06 3.73 2.00
Casson Lake (AN3) 5 24 1.92 4.64 0.98 2.28 1.89Charlton Lake 10 37 2.22 6.73 0.96 3.00 2.19
Fox Lake - Outlier 1 56 1.96 3.88 1.04 3.26 1.93Brazil Lake 5 30 2.29 6.04 1.03 3.00 2.26
Chiniguchi River 34 31 2.06 5.80 0.96 2.69 2.03Sargesson lake 1 32 1.97 5.67 0.89 2.33 1.95Kukagami Lake 25 36 2.14 5.74 0.93 2.73 2.11
Washagami Lake 7 34 1.99 5.76 0.95 2.50 1.96Bell Lake 6 24 1.91 5.17 0.97 2.98 1.89
Louie Lake 15 28 2.49 7.53 0.81 3.45 2.46Geneva Lake - Outlier 1 103 2.10 4.67 0.90 3.85 2.07
Big Swan 1 74 2.03 5.11 0.61 3.23 2.01Scadding 3 41 1.98 4.82 0.99 3.23 1.95
Makada Lake 30 39 2.11 4.81 0.90 3.79 2.09Nairn 6 72 3.75 12.05 0.84 8.16 3.70
Rathbun Lake 1 32 4.72 8.21 1.81 8.11 4.66chilled margin 7 44 2.02 5.08 0.93 2.96 2.46
Table 5-4. Summary of important features for rare-earth elements from Nipissing Gabbro
rocks. Eu/Eu* calculated using the method of Taylor and McLennan (1985). N=primitive
mantle-normalized; CN=chondrite-normalized
111
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
1W Avg 2W Avg3E Avg 4SW Avg5SW Avg 6NW7SW Avg 8E Avg9E 10E Avg11E Avg 12SW Avg13C Avg 14NW15W 16E Avg17C Avg 18SW Avg19E Avg Chilled Margin
Averages by Area
Figure 5-4. Primitive mantle-normalized multi-element diagrams for Group-1 data, a
subset of 188 samples of Nipissing Gabbro, sorted on the basis of location (Township).
Value for average chilled margin gabbro is from the current study. Normalizing values
are from McDonough and Sun (1995).
112
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
Aplite (N=2)Gabbro (N=103)Gabbronorite (N=27)Leucogabbro (N=10)Leucogabbronorite (N=4)Melagabbronorite (N=1)Olivine Gabbronorite (N=2)Olivine Leucogabbronorite (N=3)High Sulphur (>1wt% S) unclassified (N=36)Avg Chilled Margin
Averages by CIPW Rock Type
Figure 5-5. Primitive mantle-normalized multi-element diagrams for Group-2 data, a
subset of 188 samples of Nipissing Gabbro, sorted on the basis of CIPW normative rock
type. Value for average chilled margin gabbro is from the current study. Normalizing
values are from McDonough and Sun (1995).
113
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-48 JB97-49
JB98-224 JB98-207
JB98-239B JB98-239C
JB98-240 Avg Chilled Margin
Chilled Margin Samples
Figure 5-6. Primitive mantle-normalized multi-element diagrams for chilled margin
gabbro samples, Nipissing Gabbro suite. Value for average chilled margin gabbro is
from the current study. Normalizing values are from McDonough and Sun (1995).
114
Distinct negative Nb and Ta anomalies, with respect to primitive mantle-normalized data
and relative to the LILE and LREE, are attributed to crustal contamination (e.g. Cox and
Hawkesworth, 1985); Th is preferentially enriched in continental crust (McDonough and
Sun, 1995). Two of the four mixing curves were constructed by systematic introduction
of a crustal component (i.e. increasing Th) to the initial compositions of N-MORB (Sun
and McDonough, 1989) and average boninite-like rock (Piercey et al., 2001) using
Povungnituk sedimentary rocks (Lesher et al., 2001) to represent continental crust. The
third and fourth mixing curves were constructed by assuming initial primitive boninite
compositions which are predicted to have 25% and 50% less Nb relative to the boninite-
like composition of Piercey et al. (2001).
In Figure 5-7, the vast majority of the rocks plot in reasonably tight cluster that
approximates the mixing line of N-MORB and continental crust, suggesting that the
Nipissing Gabbro magmas originated from a source that was significantly contaminated
by continental crust (~20% contamination). Samples JB97-54A, RK-01, JB97-78A plot
nearer the continental crust end-member, with a composition resulting from assimilation
of local footwall rocks, which have enhanced the crustal signature common to the bulk of
the samples; these samples are extensively altered and contain several percent secondary
sulphide and blue-grey coloured quartz (JB97-78A). It is unlikely that the bulk
contamination signature was derived from local sedimentary rocks as the value for
average Huronian Supergroup sedimentary rocks plots well away from any of the mixing
curves and it would be difficult to model the majority of Nipissing Gabbro samples along
a mixing curve of N-MORB and this average Huronian sediment value.
A number of samples plot below the N-MORB mixing curve and are displaced
toward the mixing curves for Nb-depleted, boninite-like rocks (~25% depleted Nb
relative to N-MORB). These samples have depressed Nb values which indicates that the
magmas from which these rocks formed were derived from a source magma that was
very poor in Nb. Continental flood basalts or boninite-like magmas are good candidates
for this chemistry as both are significantly depleted in Nb relative to N-MORB
(boninites, more so than continental flood basalt), and are both characterized by a
continental crust signatures (Naldrett and Lightfoot, 1993; Crawford et al., 1989).
115
0.01
0.1
1
10
0.1 1 10 100
(Th/Yb)N
(Nb/
Th) N
OPX Gabbro
Gabbro
Chilled Margin
Streich Dike
Povungnituk Sediment
Huronian Sediment Avg
Boninitic Avg
N-MORB
Continental Crust
Boninitic
-25% Nb
E-MORB
-50% Nb
JB97-78A
JB97-54A
RK-01
10% crust
Average Huronian Sediment
Figure 5-7. Mixing curves for primitive mantle-normalized values of (Th/Yb)N and
(Nb/Th)N using 150 unmineralized and mineralized rock samples of Nipissing Gabbro
intrusions. Continental crust is represented by Povungnituk sedimentary rocks (Lesher et
al., 2001). Data for N-MORB and E-MORB are from Sun and McDonough (1989); data
for Streich Dike, a potential parental magma composition, is from Vogel et al. (1998a);
data for average (N=4) Huronian sedimentary rock is from Easton (2003); data for
average (N=4) Boninitic magma is from Piercey et al. (2001).
116
However, it is important to note that the values for N-MORB and E-MORB are mantle
dependent and that the mantle chemistry in the Proterozoic was probably different than
that of present day.
Some samples plot well above the N-MORB mixing curve and are displaced toward
and above the mixing curve of E-MORB and continental crust (Fig. 5-7). This suggests
the possibility of two different mantle sources; one closer to that of N-MORB with a
significant crustal component (i.e. continental flood basalt), and the second, a hybrid
magma offset toward E-MORB. To test this possibility, the same Nipissing Gabbro suite
(150 samples) was examined in the context of geographic location of the seventeen
different intrusions. Although no correlation could be made between the location of the
intrusions and their respective (Th/Yb)N and (Nb/Th)N values, there was a moderate
correlation between (Th/Yb)N and (Nb/Th)N values and those intrusions that have higher
concentrations of magmatic sulphides, and those with no significant sulphide occurrences
(Fig. 5-7). Samples from intrusions with reasonably PGE-significant sulphide contents
(i.e. Curtin, Foster, Janes, Kelly, and Louise townships) mainly plot below the N-MORB
mixing curve; all of the samples from the Charlton Lake section (Charlton Lake intrusion,
Curtin Township) and the Washagami occurrence (Kukagami Lake intrusion, Kelly
Township) plot below the N-MORB mixing curve. In contrast, samples from intrusions
with no magmatic sulphide occurrences and/or relatively insignificant PGE (Waters,
Scadding, Porter, Moncrieff, Lorne, Ermatinger, Clement, and Wells townships) mainly
plot above the N-MORB mixing curve. In general, Nipissing Gabbro intrusions with
higher concentrations of magmatic sulphides exhibit lower Nb/Ta values, suggesting that
these magmas experienced greater degrees of crustal contamination, perhaps related to
longer residence times in a staging chamber.
Chondrite-normalized REE diagrams for Group-1 and Group-2 data are shown in
Figures 5-8 and 5-9, respectively and summarized in Table 5-4. In general, Nipissing
Gabbro samples show similar and near-parallel patterns with moderate LREE enrichment
(La/Sm ~1.0-4.7; average ~2.3), whereas the HREE show only slight enrichment and are
nearly flat. The degree of fractionation of LREE to HREE, expressed as La/Yb, is
relatively wide, ranging from ~1.4 to 11.2, a reflection of the variety of rock types.
117
1
10
100
1000
La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Sam
ple/
Cho
ndrit
e
1W Avg 2W Avg3E Avg 4SW Avg5SW Avg 6NW7SW Avg 8E Avg9E 10E Avg11E Avg 12SW Avg13C Avg 14NW15W 16E Avg17C Avg 18SW Avg19E Avg Chilled Margin
Averages by Area
Figure 5-8. Chondrite-normalized REE diagrams for Group-1 data, a subset of 188
samples of Nipissing Gabbro, sorted on the basis of location (Township). Value for
average chilled margin gabbro is from the current study. Normalizing values are from
Lodders and Fegley (1998).
118
1
10
100
1000
La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Sam
ple/
Cho
ndrit
e
Aplite (N=2)Gabbro (N=103)Gabbronorite (N=27)Leucogabbro (N=10)Leucogabbronorite (N=4)Melagabbronorite (N=1)Olivine Gabbronorite (N=2)Olivine Leucogabbronorite (N=3)High Sulphur (>1wt% S) unclassified (N=36)Avg Chilled Margin
Averages by CIPW Rock Type
Figure 5-9. Chondrite-normalized REE diagrams for Group-2 data, a subset of 188
samples of Nipissing Gabbro, sorted on the basis of CIPW normative rock type. Value
for average chilled margin gabbro is from the current study. Normalizing values are from
Lodders and Fegley (1998).
119
1
10
100
1000
La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Sam
ple/
Cho
ndrit
e
JB97-48 JB97-49
JB98-224 JB98-207
JB98-239B JB98-239C
JB98-240 Avg Chilled Margin
Chilled Margin Samples
Figure 5-10. Chondrite-normalized REE diagrams for chilled margin gabbro samples,
Nipissing Gabbro suite. Value for average chilled margin gabbro is from the current
study. Normalizing values are from Lodders and Fegley (1998).
120
Europium anomalies are dominantly weakly negative with positive Eu anomalies for the
average CIPW leucogabbronorite and for average samples from the Clement, Ermatinger,
Foster and Rathbun township suites. Average chilled margin shows a very subtle
negative Eu anomaly (Fig. 5-10) as do the patterns from individual chilled margin
samples, which also have remarkably consistent profiles and narrow ranges in La/Yb
(~2.5-3.6). Conrod (1988) noted positive Eu anomalies in chilled diabase, suggesting
significant plagioclase did not crystallize prior to emplacement. In contrast, data from the
current study and from Lightfoot and Naldrett (1996) show negative Eu anomalies in
chilled diabase, suggesting plagioclase crystallization was at least in part pre-
emplacement.
In both the primitive mantle-normalized and chondrite-normalized plots, average
Huronian Supergroup sediments display a pattern that is similar to that of average aplite,
suggesting a genetic link between the aplite and Huronian Supergroup sediments.
Lightfoot and Naldrett (1989, 1996), in reporting on the prevalence of aplite in the arches
and upper stratigraphy of intrusions and the similarities of their REE patterns with
Huronian Supergroup sediments, suggested that the aplite are a hybrid product resulting
from assimilation of hangingwall rocks.
In Figure 5-11, data from 50 samples of unmineralized and mineralized Nipissing
Gabbro rocks are plotted using the values of Zr/Sm and Nb/Ta. Using the diagram after
Foley et al. (2002), all but one sample (JB98-209C, Louie Lake property) plot with very
low Nb/Ta and Zr/Sm values relative to MORB, continental crust, and modern adakites;
Foley et al. (2002) considered adakites to be rare modern analogues of Archaean crust-
building magmatism, originating by melting of a subducting basalt slab. The samples,
which include chilled margin gabbro, are tightly clustered with low Nb/Ta values similar
to that of adakites and continental crust but are displaced toward anomalously low Zr/Sm
values. These very low Zr/Sm values are probably the result of insufficient digestion
(open beaker digestion – see Section 2.2) of Zr during the ICP-MS analytical process and
so these values are shifted toward the lower left quadrant; ICP-MS Zr data may be one
third to one half less than XRF Zr data (A.J. Crawford, pers. comm., 2004). Assuming
higher Zr compositions would therefore shift these samples toward the fields of
continental crust and adakites.
121
0
5
10
15
20
25
30
1 10 100 1000
Zr/Sm
Nb/
Ta
OPX Gabbro
Gabbro
Chilled Margin
Boninitic Avg
Adakites
MORB
Primitive Mantle(intersection)
Continental Crust
JB98-209C (Louie Lake)
Figure 5-11. Plot of Zr/Sm versus Nb/Ta ratios from whole-rock analyses of 50
unmineralized and mineralized Nipissing Gabbro intrusion samples. The fields of
MORB, continental crust and adakites (modern analogues of early continental crust) are
approximated after Foley et al. (2002). Data for average (N=4) Average boninitic magma
is from Piercey et al. (2001).
122
The Nb/Ta values for the Nipissing Gabbro rocks are low (~6-13 Nb/Ta) relative to N-
MORB (~18 Nb/Ta; Sun and McDonough, 1989), and most plot lower than the field for
continental crust; a similar trend is also exhibited in the samples that plot below the N-
MORB mixing curve in Figure 5-7. These data suggest that the magmas which formed
the Nipissing Gabbro suite underwent significant crustal contamination, recording
signatures indicative of either a subduction zone environment (i.e. back-arc or boninitic
magmas), or more probable, extensive continental flood basalt magmatism.
Fitton et al. (1997) demonstrated that Icelandic basalt and N-MORB define separate
and parallel arrays on a logarithmic plot of Nb/Y vs Zr/Y. These authors found that this
plot could provide a useful discrimination between Icelandic (plume) basalt and N-
MORB whereby Nb, Zr and Y are relatively immobile during alteration of basalt and are
incompatible in the main phases of plagioclase and olivine which crystallize from the
tholeiitic magma at low pressure (Fitton et al., 2000). The value of ∆Nb, the
discrimination value, was defined by Fitton et al. (1997) as the deviation, in log units, of
Nb from the boundary between the Nb/Y vs Zr/Y arrays. Using the method described by
Baksi (2001), concentrations of Nb, Y and Zr from 5 chilled margin samples, presumed
to represent the parent magma, were used to calculate ∆Nb:
[8] ∆Nb = log (Nb/Y) + 1.74 - 1.92 log (Zr/Y)
and to speculate on the probable source of Nipissing Gabbro magmas. Baksi (2001)
proposed that positive ∆Nb values were indicative of deep-mantle sources (e.g. ∆Nb > 0
for Icelandic plumes, Reunion Island hot spot) and that negative ∆Nb values indicated
that the melts were derived from depleted sections of mantle (e.g. ∆Nb < 0 for sub-
continental lithospheric mantle contamination and arc-related magmas); ∆Nb values for
primitive mantle are ~0.18. Baksi (2001) reported conflicting results for ∆Nb in terms of
flood basalts and their inherent connection to mantle plumes (hot spots); although ∆Nb is
positive in some cases, it appears to be masked by sub-continental lithospheric
contamination (i.e. ∆Nb <0) in others. Indications of source from the calculations of
∆Nb for the 5 chilled margin samples are inconclusive as they encompass both weakly
positive (∆Nb = 0.013 and 0.094) and weakly negative (∆Nb = -0.021, -0.003 and -0.008)
values. Applying the calculation to 5 chilled margin samples from Lightfoot and Naldrett
(1996) yielded 4 positive ∆Nb values (∆Nb = 0.07, 0.11, 0.14 and 0.25) and one negative
123
∆Nb value (∆Nb = -0.09). Together, these data from Nipissing Gabbro suggest both
strong mantle signature and weak sub-continental lithospheric mantle contamination,
characteristics that Baksi (2001) proposed are indicative of either continental flood
basalts or a hybrid environment involving a subduction zone (arc lavas) and associated
mantle plume (i.e. the Tonga-Kermadec volcanic arc and Samoan plume).
5.2.3 Chalcophile (PGE, Cu, Ni) Element Variations
The most prevalent type of sulphide mineralization in the Nipissing Gabbro suite is
stratabound PGE sulphide mineralization, which occurs within the lower to middle parts
of the orthopyroxene gabbro unit (e.g. Lightfoot and Naldrett, 1996; Jobin-Bevans et al.,
1998, 1999; James et al., 2002b). This style of sulphide mineralization is dominated by
chalcopyrite and pyrrhotite with subordinate pentlandite and rare pyrite, and generally
consists of 1-5% fine- to medium-grained disseminated and blebby sulphide (see Section
4.6). A summary of the average chalcophile metals plus Au, along with important metal
ratios, for mineralized and unmineralized samples (188 samples) is provided in Table 5-
5; summaries of unmineralized samples (59 samples with <0.05 wt% S) and mineralized
samples (24 samples with >0.05 wt% S) are provided in Tables 5-6 and 5-7, respectively.
Mineralized samples average ~2.7 Pd/Pt (median ~1.6) and ~6.7 Cu/Ni (median ~2.0),
and unmineralized samples average ~2.0 Pd/Pt (median ~1.2) and ~0.7 Cu/Ni (median
~0.7). In general, samples with high PGE concentrations (i.e. >1000 ppb Pt+Pd) have
high Pd/Pt ratios (i.e. >3.0) and high Cu/Ni ratios (i.e. >2.0).
Background concentrations of PGE, Au, Cu and Ni are estimated to have maximum
values of about 3.7 ppb Au (median ~2.9 ppb), 12.4 ppb Pt (median ~10.9 ppb), 20.5 ppb
Pd (median ~14 ppm), 91 ppm Cu (median ~93 ppm), and 149 ppm Ni (median ~140
ppm); these arithmetic averages and median values are based on the 59 unmineralized
(<0.05 wt% S) samples as listed in Table 5-6. James et al. (2002b) reported somewhat
higher estimates of background concentrations with maximum values of ~9 ppb Au, 32
ppb Pt, 40 ppb Pd, 94 ppm Cu, and 376 ppm Ni. PGE concentrations for average chilled
margin (two samples) are ~3.4 ppb Au, ~10.6 ppb Pt, ~11.6 ppb Pd, 120 ppm Ni and 124
ppm Cu with metal ratios of 1.1 Pd/Pt and 1.0 Cu/Ni. The PGE tenor of the chilled
margin samples (~22 ppb Pt+Pd) is high relative to common mafic magmas (e.g. Hamlyn
and Keays, 1986).
124
Selected bivariate plots of chalcophile element concentrations for Nipissing Gabbro
rocks (188 samples) are provided in Figure 5-12. In general, correlations between the
chalcophile elements are good (i.e. Pd-Pt, Cu-Se, Cu-Pd and Cu-Pt), indicating that the
PGE are strongly sulphide controlled; bivariate plots of S-Pd, S-Pt, Ni-Pd and Ni-Pt also
show good correlation.
Intrusion N Pt Pd Ni Cu S/Se Pd/Pt Cu/Ni Cu/Pd Pd/Ir
ppb ppb ppm ppmBasswood Lake 16 6.36 5.81 71 436 3859 0.9 6.2 74939 21.8Appleby Lake 12 3.21 3.53 83 154 3564 1.1 1.9 43631 11.9Manitou Lake 9 1.81 2.83 99 128 2226 1.6 1.3 45163 2.1Charlton Lake 5 69.15 109.21 428 661 3382 1.6 1.5 6055 378.7Charlton Lake 10 9.91 23.87 169 257 1946 2.4 1.5 10750 95.6
Fox Lake (Outlier) 1 1.43 1.93 78 170 1852 1.3 2.2 88083 7.1Brazil Lake 5 1.43 26.59 1343 132 5675 18.6 0.1 4965 98.5
Chiniguchi River 34 171.20 1112.15 1615 3724 1767 6.5 2.3 3349 1969.8Sargesson lake 1 101.00 116.60 1116 3217 1355 1.2 2.9 27590 457.3Kukagami Lake 25 45.45 169.29 341 563 2526 3.7 1.7 3327 643.1
Washagami Lake 7 18.24 58.39 164 163 1544 3.2 1.0 2789 266.8Bell Lake 6 10.88 5.45 301 30 1716 0.5 0.1 5474 5.8
Louie Lake 15 27.22 46.93 1044 448 20490 1.7 0.4 9554 74.8Geneva Lake (Outlier) 1 1.43 1.88 44 190 3271 1.3 4.3 101064 7.0
Big Swan 1 9.07 9.12 45 75 4598 1.0 1.7 8224 33.8Scadding 3 8.81 7.33 110 118 1254 0.8 1.1 16136 31.4
Makada Lake 30 6.53 7.97 664 204 56720 1.2 0.3 25539 18.1Nairn 6 62.64 50.22 5360 6353 7541 0.8 1.2 126502 7.8
Rathbun Lake 1 3961.00 6230.00 9367 377129 1187 1.6 40.3 60534 19110.4Chilled Margin 7 9.44 11.37 117 125 2411 1.2 1.1 11022 53.4
Table 5-5. Summary of average chalcophile metals and ratios from 188 mineralized and
unmineralized Nipissing Gabbro samples.
125
Intrusion N Pt Pd Ni Cu S/Se Pd/Pt Cu/Ni Cu/Pd Pd/Irppb ppb ppm ppm
Basswood Lake 6 11.56 11.41 80 122 1772 1.0 1.5 11 43.9Manitou Lake 1 4.02 4.42 100 150 1444 1.1 1.5 34 0.5Charlton Lake 4 20.44 40.51 173 111 1258 2.0 0.6 3 384.0Charlton Lake 4 6.37 16.41 124 116 1691 2.6 0.9 7 74.6
Brazil Lake 6 1.43 1.69 85 66 2128 1.2 0.8 39 6.3Chiniguchi River 9 17.06 29.04 140 93 1205 1.7 0.7 3 111.0Kukagami Lake 3 9.59 11.14 142 114 1627 1.2 0.8 10 55.8
Washagami Lake 6 25.88 77.60 173 147 1355 3.0 0.8 2 400.0Bell Lake 1 10.88 5.45 301 30 1716 0.5 0.1 5 5.8
Louie Lake 1 33.20 29.80 99 34 2143 0.9 0.3 1 143.3Scadding 16 11.00 14.00 140 86 1400 1.3 0.6 6 35.0
Makada Lake 1 7.03 6.29 240 55 2208 0.9 0.2 9 11.7Nairn 1 2.18 18.07 140 58 568 8.3 0.4 3 66.9
Chilled Margin 2 10.60 11.61 120 124 1834 1.1 1.0 11 43.0AVERAGE: 12.36 20.45 149 91 1578 2.0 0.7 10 103.0
MEDIAN: 10.88 14.00 140 93 1627 1.2 0.7 6 55.8
Table 5-6. Summary of average chalcophile metals and ratios from 59 unmineralized
(<0.05 wt% S) Nipissing Gabbro samples, a subset of the 188 samples, and chilled
margin gabbro samples. The averages from the 59 samples provide an estimate of
background concentrations.
Intrusion N Pt Pd Ni Cu S/Se Pd/Pt Cu/Ni Cu/Pd Pd/Irppb ppb ppm ppm
Charlton Lake 1 264 384 1447 2863 3667 1.5 2.0 7.5 376.5Chiniguchi River 6 457 3419 4559 10342 1648 7.5 2.3 3.0 2421.3Kukagami Lake 2 410 1740 2718 5677 2933 4.2 2.1 3.3 2320.0
Louie Lake 7 44 85 2067 812 21244 1.9 0.4 9.5 68.6Makada Lake 2 15 22 1871 1026 115962 1.5 0.5 47.6 35.8
Nairn 5 75 57 6404 7611 7552 0.8 1.2 134.4 7.4Rathbun Lake 1 3961 6230 9367 377129 1187 1.6 40.3 60.5 19110.4
AVERAGE: 746.5 1705.2 4062 57923 22028 2.7 7.0 38 3477.1MEDIAN: 264.0 384.0 2718 5677 3667 1.6 2.0 10 376.5
Table 5-7. Summary of average chalcophile metals and ratios from 24 mineralized (>0.05
wt% S) Nipissing Gabbro samples, a subset of the 188 samples.
126
0.1
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100
1000
10000
0.01 0.1 1 10 100 1000 10000
Pd (ppb)
Pt (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples)(A)
0.01
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1000
10000
1 10 100 1000 10000 100000 1000000
Cu (ppm)
Pd (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples)
(B)
Figure 5-12a. Bivariate plots of whole-rock chalcophile elements Pd-Pt and Cu-Pd (188
Nipissing Gabbro samples). Average chilled margin gabbro is from the current study.
127
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10000
1 10 100 1000 10000 100000 1000000
Cu (ppm)
Pt (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples)
(C)
0.1
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100
1000
10000
1 10 100 1000 10000 100000
Ni (ppm)
Pt (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples)(D)
Figure 5-12b. Bivariate plots of whole-rock chalcophile elements Cu-Pt and Ni-Pt (188
Nipissing Gabbro samples). Average chilled margin gabbro is from the current study.
128
The majority of samples have S/Se ratios that range between 1000 and 5000 (Fig. 5-13a)
which is well within the range of uncontaminated magmatic sulphides (Naldrett, 1981),
approximating that of mantle (~3300 S/Se; McDonough and Sun, 1995). Those samples
that plot higher than 5000 comprise semi-massive to massive (pyrrhotite-dominated)
sulphide mineralization, whereas those samples lower than 1000 can be explained in
terms of S loss, most likely due to secondary processes such as weathering and/or
degassing (Reeves and Keays, 1995), or as a result of relative enrichment in Se, which is
also highly chalcophile (DSe ~700, Keays and Lightfoot, 2004; DSe ~1,770, Peach et al.
1994) and so competes with S in early fractionating sulphides, resulting in lower S/Se
ratios. Sample JB97-39C (18SW; Nairn Township), which has the lowest S/Se value of
568, is a medium-grained quartz gabbro with local patches of <1% disseminated
sulphide. This sample, which has very low visible sulphide, was collected from massive
gabbro immediately adjacent to semi-massive and massive sulphide pod, associated with
blue quartz eyes and hosted by medium- to coarse-grained gabbro (samples JB97-39A
and 39B). It is possible that the S loss noted in JB97-39C was a consequence of the
leaching/migration of sulphur from the host gabbro and accumulation (remobilization)
into a massive sulphide pod. The Rathbun Lake occurrence, considered to be
characteristic of hydrothermal, remobilized Cu-Ni sulphide mineralization (Rowell and
Edgar, 1986), is represented in the current Nipissing Gabbro sample suite by sample
JB98-190E (Pt+Pd = 10191 ppb). In terms of S/Se, this sample plots within the range of
magmatic sulphides (1187 S/Se). However, the Pd/Ir ratio, a measure of hydrothermal
versus magmatic sulphide (Keays et al., 1982), is extremely high at 19,110 Pd/Ir, as is the
Cu/Ni ratio of ~40; the Pd/Pt ratio is also elevated at ~1.6. These signatures of
hydrothermal mineralization (elevated Pd/Ir and Cu/Ni), combined with the magmatic
S/Se value are suggestive of remobilized, hydrothermal sulphide sourced from what was
originally magmatic sulphide.
Concentrations of Pd are plotted against values of (La/Sm)N and (Th/Nb)N in Figures
5-13b and 5-13c, respectively. The Pd versus (La/Sm)N plot, and especially the Pd versus
(Th/Nb)N plot show that most of the rocks have values that are higher than mantle (~5
(Th/Nb)N, ~2 (La/Sm)N) and have fairly constant ratios, indicating a degree of crustal
contamination that is remarkably similar and uniform.
129
0.01
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1 10 100 1000 10000 100000 1000000 10000000 100000000
S/Se
Pd (p
pb)
6NW 14NW1W 2W15W 4SW5SW 7SW12SW 18SW13C 17C3E 8E9E 10E11E 16E19E Chilled Margin Avg
(188 samples)
sulphur loss magmatic
contamination
+R-factor
209D
209B117C
39B
33
39A
39C
54A
RK-4
165
83
190E(A)
Figure 5-13a. Bivariate plots of whole-rock S/Se versus Pd for 188 Nipissing Gabbro
rock samples. Average chilled margin gabbro is from the current study.
130
0.01
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1
10
100
1000
10000
0.1 1 10
(La/Sm)N
Pd (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples) assimilation of crust(contamination)
54A
190E(B)
0.01
0.1
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100
1000
10000
0.1 1 10 100
(Th/Nb)N
Pd (p
pb)
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(188 samples)
assimilation of crust(contamination)
(C)
Figure 5-13bc. Bivariate plots of whole-rock (B) (La/Sm)N-Pd, and (C) (Th/Nb)N-Pd. for
188 Nipissing Gabbro samples. Average chilled margin gabbro is from current study.
131
Given the enormous size of the sampling area and the high variability in rock types
sampled, this suggests that contamination principally occurred either in a large deep-
seated chamber or by the assimilation of country rocks that had very uniform (La/Sm)N
and (Th/Nb)N ratios. As the (Th/Nb)N ratios do not increase significantly with
fractionation, this trend is indicative of bulk contamination. Similar contamination
signatures were reported for crustally contaminated Nadezhdinsky lavas (Siberian Traps)
at Noril’sk (Lightfoot et al., 1994; Lightfoot and Keays, 2004).
Some of the samples from the same intrusions within the main trend (i.e. Makada
Lake (17C), Nairn (18SW), and Louie Lake (13C); Fig. 1-2), have much higher (Th/Nb)N
ratios, suggesting a second phase of contamination, perhaps at a higher crustal level
relative to the deeper chamber, and/or at the site of emplacement which invokes a local
contamination effect. Moreover, these same samples also have counterparts that exhibit
much lower (Th/Nb)N ratios. All of these sample locations show evidence for
assimilation of country rocks (e.g. fragments of local country rock mixed in with
mineralized gabbro) indicating that the signature for local contamination is characterized
by both high and low (Th/Nb)N values, relative to the bulk contamination trend. Perhaps
the most important feature of these plots is that there is no correlation between the
concentrations of Pd and the values of either (La/Sm)N or (Th/Nb)N. This is interpreted
to mean that the main mineralizing event is probably related to the bulk contamination
signature rather than the affects of local country rock contamination.
The bivariate plot of MgO versus Ir, shown in Figure 5-14, can provide a measure of
fractionation whereby the more primitive rocks types will comprise higher MgO and Ir
compositions and increasing fractionation will produce ever lower MgO and Ir
concentrations. Samples that are weakly to strongly mineralized exhibit elevated Ir
concentrations coupled with wide variations in MgO compositions. This indicates that
mineralization can occur in rocks with either high MgO or low MgO and that the
concentration of MgO is not necessarily indicative of the mineralizing potential of the
intrusion.
132
0.01
0.1
1
10
100
0510152025
MgO (wt%)
Ir (p
pb)
6NW 14NW1W 2W15W 4SW5SW 7SW12SW 18SW13C 17C3E 8E9E 10E11E 16E19E Chilled Margin Avg
(188 samples)
Figure 5-14. Bivariate scatter diagram of MgO versus Ir for 188 Nipissing gabbro rock
samples. Value for average chilled margin gabbro is from the current study.
Concentrations of Ir that are at or below ~0.1 ppb are at or near the lower limits of
detection.
133
Discrimination plots such as Ni/Cu versus Pd/Ir (Fig. 5-15a) and Cu/Ir versus Ni/Pd
(Fig. 5-15b) are useful to determine the effects of partial melting and if and when,
sulphide segregation occurred (Barnes et al., 1988; Barnes, 1990); increased partial
melting of the mantle lowers Ni/Cu and increases Pd/Ir and increases Cu/Ir and lowers
Ni/Pd. In both discrimination plots, the majority of the mineralized and unmineralized
Nipissing Gabbro samples plot within the region of layered intrusions (Barnes et al.,
1988) with sample JB98-190E from Rathbun Lake (19E) plotting within the field of
hydrothermal or secondary sulphides. A grouping of least fractionated samples, trending
along the positive olivine vector in both discrimination plots (lower right in Ni/Cu-Pd/Ir
and upper left in Cu/Ir-Ni/Pd), mainly consist of samples from Lorne Township (12SW;
Bell Lake intrusion), Waters Township (17C; Makada Lake intrusion) and Nairn
Township (18SW; Nairn Intrusion); these samples also contain elevated MgO and Ir
concentrations (Fig. 5-14). This suggests that these rocks may have been olivine-bearing;
the majority of these same samples are CIPW olivine-normative. Average chilled margin
samples plot within the field of layered intrusions (Barnes et al., 1988) on Cu/Ir versus
Ni/Pd (Fig. 5-15b) and within the overlap region for the fields of layered intrusions and
flood basalts (Barnes et al., 1988) on Ni/Cu versus Pd/Ir (Fig. 5-15a).
The plot of Se versus Pd (Fig. 5-16) is useful for discriminating between rocks that
formed from S-undersaturated (second-stage or fertile) versus S-saturated (first-stage or
infertile) magmas such as MORB (Peck et al., 2001). With the exception of two samples
(JB-98-120 and 121A), all of the unmineralized Nipissing Gabbro samples, including
average chilled margin, plot within the field of S-undersaturated, second-stage magmas,
implying that parental magmas to Nipissing Gabbro were PGE metal-fertile magmas that
had not previously segregated sulphides. The two samples that plot within the first-stage
magma field (1W; Basswood Lake intrusion), are vari-textured to granophyric gabbro
and have very low Pd concentrations. Measurement of Pd concentrations at this low
level could result in erroneous and unreliable data. All six samples from the Lorne
Township (12SW; Bell Lake intrusion) location form a distinct group well within the
field of second-stage (fertile) magmas.
134
0.01
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100
1000
10000
100000
0.01 0.1 1 10 100 1000
Ni/Cu
Pd/Ir
6NW 14NW1W 2W15W 4SW5SW 7SW12SW 18SW13C 17C3E 8E9E 10E11E 16E19E Chilled Margin Avg
(all samples - 188)
Rathbun
hydrothermal
increased fractionation
mantle
+olivine
+chromite
(A)
layered intrusions
Figure 5-15a. Discrimination diagram of Ni/Cu versus Pd/Ir for the 188 Nipissing
Gabbro rock samples. This diagram is useful to determine the effects of partial melting
whereby increased partial melting of the mantle lowers Ni/Cu and increases Pd/Ir
(Barnes et al., 1988; Barnes, 1990). The fields of mantle, layered intrusions and
hydrothermal are approximated from Barnes (1990).
135
100
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100000
1000000
10000000
100 1000 10000 100000 1000000 10000000 100000000 1000000000 10000000000
Cu/Ir
Ni/P
d
6NW14NW1W2W15W4SW5SW7SW12SW18SW13C17C3E8E9E10E11E16E19EChilled Margin Avg
(all samples - 188)
Region Layered Intrusions, Flood Basalts High MgO Basalts and PGE Reefs
S-undersaturation(late S-saturation)
Rathbun - hydrothermal(JB98-190E)
Waters (RK-4)
+olivine
+chromite
+sulphide or PGM
(B)
Figure 15-b. Discrimination diagram of Cu/Ir versus Ni/Pd for the 188 Nipissing Gabbro
rock samples. This diagram is useful to determine the effects of partial melting whereby
increased partial melting of the mantle increases Cu/Ir and lowers Ni/Pd (Barnes et al.,
1988; Barnes, 1990). Average chilled gabbro is from the current study. The overlapping
field of layered intrusions, flood basalts and high MgO basalts is adapted from Barnes
(1990).
136
As discussed earlier, these samples occur along distinct trends in the MgO-Ir, Cu/Ir-Ni-
Pd and Ni/Cu-Pd/Ir plots, indicating that these rocks are much more primitive (olivine-
bearing?) relative to other sampled Nipissing Gabbro rocks.
Primitive mantle-normalized PGE and chalcophile element diagrams (recalculated to
100% sulphide) for average unmineralized samples (59 samples), sorted by location, and
chilled margin gabbro, are shown in Figure 5-17. All of the Nipissing Gabbro sulphides
from mineralized and unmineralized samples are characterized by varying degrees of
positive slopes and define two distinct sets of profiles as shown in Figure 5-17 (<0.05
wt% S) and Figure 5-18 (>0.05 wt% S). In Figure 5-17, unmineralized samples from
Lorne (12SW), Nairn (18SW) and Waters (17C) townships, display profiles that are
relatively elevated in Ni-Ir-Ru-Rh concentrations; samples from the Nairn (18SW)
intrusion show the highest Pd-Au-Cu concentrations. In Figure 5-18, mineralized
samples from Louise (13C), Nairn (18SW) and Waters (17C) townships have sulphide
patterns that are distinctly depleted in Pt-Pd-Au-Cu concentrations; excluding the sample
from Rathbun Lake (19E), which is considered representative of hydrothermal sulphide
(Rowell and Edgar, 1986), mineralized samples from Louise (13C) and Waters (17C)
show the lowest overall PGE concentrations. In Figure 5-18, the sulphide patterns
exhibited by the four averages of mineralized Nipissing Gabbro intrusions (4SW, 8E, 10E
and 19E) closely resemble the profile from East Bull Lake hydrothermal mineralization,
with depleted Ni-, Ir, Ru and Rh versus moderately elevated Pt, Pd, Au and Cu.
The majority of mineralized and unmineralized samples define patterns that are
typical of those displayed by known magmatic sulphides, confirming the magmatic
nature of these sulphides. In addition, the patterns are similar to that of average chilled
margin of Nipissing Gabbro and more significantly, average continental flood basalt
(Naldrett, 1981). Figure 5-17b shows, in detail, the strong similarity between sulphides
from chilled margin samples of Nipissing Gabbro and average flood basalt (Naldrett,
1981). This is important in that it suggests that the magmas which generated the
magmatic PGE in the Nipissing Gabbro suite were probably generated as a result of
continental flood basalt magmatism. The ratio of Pd/Ir can be used to estimate the degree
of fractionation that a magma has undergone, whereby Pd behaves incompatibly and is
concentrated in more fractionated magmas (Keays et al., 1982).
137
0.1
1
10
100
1000
10000
0.1 1 10 100 1000 10000 100000
Se (ppb)
Pd (p
pb)
1W4SW5SW7SW12SW18SW13C17C3E8E10E11E16EChilled Margin AvgMORB
(<0.05 wt% S)
First-Stage Magmas (MORB)
Second-Stage Magmas (Fertile)
Average MORB
Figure 5-16. Discrimination diagram of Se versus Pd plotting average unmineralized
samples (59 samples), sorted by location. The plot of Se versus Pd is useful for
discriminating between rocks that formed from S-undersaturated (second-stage or fertile)
versus S-saturated (first-stage or infertile) magmas such as MORB (Peck et al., 2001).
Value for average chilled margin gabbro is from the current study. Value for average
MORB is from Hamlyn and Keays (1986).
138
1
10
100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
1W Avg4SW Avg5SW Avg7SW8E Avg10E Avg11E Avg12SW Avg13C16E17C Avg18SWChilled Margin AvgFlood Basalt AvgEBL Hydrothermal AvgRiver Valley Mineralized
averages with <0.05 wt% S
LORNE
NAIRN
WATERS
River Valley (Breccia Unit)
East Bull Lake - hydrothermal
(A)
Figure 5-17a. Primitive mantle-normalized PGE diagrams (metal in 100% sulphide) for
average unmineralized Nipissing Gabbro (59 samples). Average chilled gabbro and
average mineralized River Valley are from this study; average flood basalt from Naldrett
(1981); average East Bull Lake hydrothermal mineralization from Peck et al. (1993b).
Mantle normalizing values are from Barnes et al. (1988) and McDonough and Sun
(1995).
139
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
Chilled Margin Avg
JB98-239C
JB98-240
Flood Basalt Avg
Average Flood Basalt (Noril'sk)
(B)
Figure 5-17b Primitive mantle-normalized PGE diagrams (metal in 100% sulphide) for
chilled margin gabbro from Nipissing Gabbro. Average chilled gabbro is from this study.
Average flood basalt (Siberian Traps) is from Naldrett (1981); average East Bull Lake
hydrothermal mineralization from Peck et al. (1993b). Mantle normalizing values are
from Barnes et al. (1988) and McDonough and Sun (1995).
140
0.1
1
10
100
1000
10000
100000
1000000
10000000
100000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
4SW
8E Avg
10E Avg
13C Avg
17C Avg
18SW Avg
19E
Chilled Margin Avg
Flood Basalt Avg
River Valley Mineralized
EBL Hydrothermal Avg
averages with >1.0 wt% S
LOUISENAIRN
WATERS
River Valley (Breccia Unit)
Figure 5-18. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for average mineralized Nipissing Gabbro
samples (24 samples), sorted by location (township). Data for average chilled margin
and average unmineralized River Valley are from this study; average flood basalt is from
Naldrett (1981); data for mineralized River Valley intrusion from this study; average East
Bull Lake hydrothermal mineralization is from Peck et al. (1993b). Mantle normalizing
values are from Barnes et al. (1988) and McDonough and Sun (1995).
141
In Figure 5-17, several samples (Lorne (12SW), Nairn (18SW) and Waters (17C) have
much lower Pd/Ir values relative to that of average continental flood basalt (Naldrett,
1981). Recent work by Lightfoot and Keays (2004) has shown that sulphide from the
Nadezhdinsky flood basalts (Siberian Trap, Noril’sk) contain in general several ppb PGE
and formed by up to 25% fractionation of its parent S-undersaturated magma. The low
Pd/Ir values (Fig. 5-17b), which are due to elevated Ir concentrations, indicates that these
sulphides were formed from magmas that were not as fractionated as those magmas
which produced the sulphides in average continental flood basalt (Naldrett, 1981).
5.2.4 Modelling of Sulphide Compositions
The sulphide compositions of 66 unmineralized (<0.05 wt% S) and 97 mineralized
(>0.05 wt% S) rock samples from various Nipissing Gabbro intrusions were modelled
using the mass balance R factor equation of Campbell and Naldrett (1979) as described in
Section 2.3.5. Utilizing the Pd versus Cu/Pd diagram of Barnes et al. (1993) the
modelling curves (R factor tie lines) are plotted along with the Pd and Cu/Pd values from
the 163 samples (Fig. 5-19). The average Cu and Pd abundances from the 66
unmineralized samples are used as the best estimate for the parental magma composition
(88 ppm Cu, 15 ppb Pd, 5855 Cu/Pd, 0.03 wt% S).
The majority of mineralized sample sulphides can be modelled using R factors that
are much less than 100 (Fig. 5-19), although a number of these samples fall between R
factors of 100 and 1000. The sulphide that can be modelled using the highest R factor
values (i.e. >1000) are primarily from the Chiniguchi River and Kukagami Lake
intrusions, specifically the Rastall (Janes Township) and Washagami Lake (Kelly
Township) occurrences and the Whalen showing in Kelly Township (Fig. 1-2). The
majority of unmineralized sample sulphides can be modelled using R factors of less than
100 and many of these sulphides fall below the sulphide-silicate tie line for R=100,000.
The results suggest that sulphides from the areas with the highest PGE grades (i.e. Rastall
occurrence, Washagami occurrence and Whalen showing; see below) experienced the
highest R factors (~1000 to 2,000). For comparison, it is notable that calculated R factors
for disseminated magmatic sulphide from several intrusions, related to intraplate
magmatism, include 1000 to 20,000 for Noril’sk-Talnakh, 200 to 2000 for Cape Smith,
142
2000 to 10,000 for the Duluth Complex, and 200 to 2000 for the Muskox intrusion
(Barnes et al., 1997).
1
10
100
1000
10000
100000
1000000
10000000
100000000
0.01 0.1 1 10 100 1000 10000 100000 1000000
Pd (ppb)
Cu/
Pd
>0.05 wt% S<0.05 wt% S
MANTLE
DEPLETED
ENRICHED
100%
100%
R=100R=1000
R=10,000
R=100,000
R=2000
0.1%1.0% 10%
Estimated Parental Magma
Figure 5-19. Discrimination plot of Pd versus Cu/Pd showing the sulphide compositions
of 97 mineralized (>0.05 wt% S) and 66 unmineralized (<0.05 wt% S) rocks from
Nipissing Gabbro intrusions. Tie lines are mixing lines between sulphide and silicate melt
at various R factors, ranging from 100 to 100,000, and determined after methods
described by Campbell and Naldrett (1979) and Naldrett (1981). Markers along each of
the mixing lines represent percentages of precipitated sulphide melt at 0.1%, 1.0%, and
10% through to 100% sulphide. The star symbol represents the estimated parental magma
composition derived from the average composition of 66 unmineralized (<0.05 wt% S)
rocks (88 ppm Cu, 15 ppb Pd, 0.03 wt% S), and assuming a sulphide component of 36.5
wt% S. Fields of mantle rocks, and those depleted and enriched in PGE relative to
mantle are taken from Barnes et al. (1993).
143
Most of the mineralized (>0.05 wt% S) samples lie above the Cu/Pd line of mantle
values and the majority of these have values that are above that of mantle and in the field
of depleted PGE (Fig. 5-19). The significance of this is that, prior to their emplacement,
the magmas that formed the Nipissing Gabbro intrusions had probably undergone
sulphide fractionation with the removal of a very small amount of sulphides, possibly
within a staging magma chamber at deeper crustal depths. These magmas, which were S-
saturated, underwent adiabatic decompression during their ascent through the crust,
which increased the S-capacity of the magma (Mavrogenes and O’Neill, 1999) and
returned them to a state of S-undersaturation; a phenomenon that has been recognized in
the East Greenland rifted margin magmas and as an important factor in driving
continental flood basalts to S-undersaturation (Momme et al., 2002b). It appears as
though the magma maintained S-undersaturation en route through the crust until
emplacement as Nipissing Gabbro intrusions in the higher level supracrustal rocks. The
magmas then became S-saturated, likely through normal fractionation and cooling, and
segregated sulphides at the various R factors indicated in Figure 5-19. The majority of
unmineralized and mineralized samples plot with higher Cu/Pd values, indicating that the
magma from which these sulphides precipitated became S-saturated at higher Cu/Pd and
lower Pd values than the estimated initial magma composition (star symbol, Fig. 5-19).
Using the value of average chilled margin gabbro (11.4 ppb Pd, 125 ppm Cu, 10965
Cu/Pd, 0.06 wt% S) as the initial composition of the magma also failed to account for the
distribution of these anomalous samples. This suggests that the estimated initial
composition for Pd (~11-15 ppb) is too high to explain all of the sulphide compositions
and/or that more than one magma composition is required to explain the variations in the
sulphide compositions.
5.3 Basswood Lake Intrusion - Traverse
The Basswood Lake intrusion, a relatively large body of Nipissing Gabbro that
extends parallel to and northeast (~2 km) of the Murray Fault Zone, is located north of
Thessalon on Highway 129, within Bridgland, Wells, Kirkwood and Day Townships
(Figs. 1-2 and 5-20). Fourteen samples were collected along Highway 129 which
provides a well-exposed section (~7 km wide) through the intrusion. This section follows
the same portion of intrusion that was reported on by Lightfoot et al. (1986, 1987, 1993).
144
A sample summary is provided in Table 5-8 and sample locations are shown in Figure 5-
20; a full listing of the data is provided in Appendix 1.
5.3.1 Geology and Mineralization
The Basswood Lake intrusion is hosted by Huronian Supergroup (Gowganda and
Lorrain formations) sedimentary rocks but contacts between the two are not exposed in
the immediate area of the section. Exposed bedrock along the sample section rises from
about 240 m above sea level (ASL) at the southern end, through a central plateau that
ranges from 300-310 m ASL and then increases northward to a peak of about 320 m ASL
at the northern end of the section, at which point overburden covers the bedrock. The
southern margin of the intrusion is locally sheared with numerous narrow (centimetre-
scale) sulphide-bearing (pyrite-chalcopyrite) quartz-carbonate veins occurring within 10s
of metres of the projected contact; Lightfoot et al. (1993) described similar features. The
northern margin of the intrusion is marked by a gradual reduction in grain size
(approaching chilled textures) toward the covered contact region (Fig. 5-20).
From south to north, the sample suite comprises fine- to medium-grained quartz
gabbro, medium-grained orthopyroxene gabbro, medium- to coarse-grained granophyric
and vari-textured gabbro (Photo 4-10), medium- to coarse-grained granophyric gabbro
with pegmatitic patches and aplite veins and dikes (Photo 5-1a), medium-grained quartz
gabbro and orthopyroxene gabbro, and finally fine-grained quartz gabbro. Sample JB97-
65 was collected from an elongate granophyric pod or dike (Photo 4-12), hosted by
medium- to coarse-grained granophyric gabbro, and located about mid-way through the
sample section. Several fragments of sedimentary rock in medium-grained gabbro were
observed in the middle to northern portion of the traverse, in the area of JB97-63 (Photo
5-1b).
Lightfoot et al. (1993) interpreted the Highway 129 section to represent the exposed
basal and upper portion of the sill and described a stratigraphy, from south to north,
consisting of quartz diabase, hypersthene diabase with vari-textured patches, and
granophyric diabase which is transitional into capping quartz diabase. However, current
geochemical evidence and the prevalence of granophyric-aplitic rocks toward the centre
of the section, suggests that this section of the sill represents an unroofed and eroded
antiformal arch portion of the intrusion with lithologies and geochemical trends mirrored
145
on either side of the axial plane (Fig. 5-21). It is notable that the implied strike of the
axial plane (~300 Az) for the antiform parallels that of many of the sulphide-bearing
quartz carbonate veins which cut the intrusive body (i.e. samples JB98-121A, 121B),
suggesting a regional non-penetrative fabric.
Figure 5-20. General geology and sample locations from the Basswood Lake intrusion,
Bridgland, Wells, Kirkwood and Day townships. Geology modified after Ontario
Geological Survey Map 2419 (1979). The location of the Appleby Lake sample section
is outlined and shown in Figure 5-27
146
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB98-118 G (Q-H) 0.033 187 104 - 0.24 1.08 8.16 23.36JB97-61 OLGN (H-O) 0.070 457 118 - - - - -JB97-62 G (Q-H) 0.040 294 112 - - 1.05 11.13 8.24JB97-63 G (Q-H) 0.080 511 82 - - 0.15 11.02 1.83JB97-64 LG (Q-H) 0.080 361 44 - - - - -JB97-65 aplite 0.130 200 14 - - - - -JB97-66 LG (Q-H) 0.050 288 44 - - - - -
JB98-119 G (Q-H) 0.061 294 60 - 0.14 - - 0.12JB98-120 G (Q-H) 0.016 206 56 - 0.17 - 7.17 0.99
JB98-121A LG (Q-H) 0.044 89 34 0.38 12.08 7.84 - 0.20JB98-121B altered gabbro 4.120 9056 60 - - - - 0.08JB98-122 LG (Q-H) 0.047 253 41 - 0.31 0.14 9.94 2.46JB98-123 GN (H-O) 0.038 201 130 0.10 0.26 0.43 31.50 33.20JB98-124 G (Q-H) 0.052 269 109 - 0.22 0.26 10.07 11.45
Sample CIPW Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)NNorm wt% ppb ppm ppm
JB98-118 G (Q-H) 4.31 140 1765 2.9 1.3 56 64.1 2.39JB97-61 OLGN (H-O) 5.04 78 1532 - 0.7 45 173.3 2.32JB97-62 G (Q-H) 3.79 120 1361 0.7 1.1 54 54.4 2.30JB97-63 G (Q-H) 14.5 264 1566 0.2 3.2 44 90.3 2.61JB97-64 LG (Q-H) 7.6 217 2216 - 4.9 31 110.8 2.60JB97-65 aplite 5.88 91 6500 - 6.5 22 36.1 0.89JB97-66 LG (Q-H) 6.44 111 1736 - 2.5 32 121.7 2.79
JB98-119 G (Q-H) 1.34 279 2075 - 4.7 36 112.1 2.66JB98-120 G (Q-H) 7.36 175 777 0.1 3.1 40 114.7 2.48
JB98-121A LG (Q-H) 1.16 49 4944 - 1.4 38 134.3 2.66JB98-121B altered gabbro 4.19 4769 4549 - 79.5 41 148.5 2.02JB98-122 LG (Q-H) 3.01 155 1858 0.2 3.8 34 141.7 2.73JB98-123 GN (H-O) 6 92 1891 1.1 0.7 72 27.6 1.99JB98-124 G (Q-H) 3.02 108 1933 1.1 1.0 65 41.0 2.21
Table 5-8. Summary of whole-rock geochemical characteristics for samples from the
Basswood Lake intrusion, Kirkwood, Wells and Bridgland townships. "-" below lower
limit of detection; "N" = primitive mantle-normalized; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-
O=hypersthene-olivine. Norm wt% = rock types determined on the basis of weight
percent normative minerals calculated to normative weight percent.
147
There are no known occurrences of significant sulphide mineralization in the
Basswood Lake intrusion. With the exception of sample JB98-121B and to a lesser
extent JB98-121A, none of the samples collected from the Basswood Lake intrusion have
any appreciable (>1%) visible sulphide (Photo 4-13). Sample JB98-121B was collected
from a medium- to coarse-grained, altered granophyric gabbro with disseminated and
stringer sulphide (up to 15% chalcopyrite-pyrite), which occurred within an ~1-2 metre
wide alteration zone (pink- to red-stained hematitic(?) alteration; supergene
mineralization) that continues across the highway exposure and through the area of
sample JB98-121A (Fig. 5-20).
Figure 5-21. Schematic diagram showing the interpreted structure of the Basswood Lake
and Appleby Lake intrusions, Wells Township. The arrows (F) indicate the direction of
migrating fractionated fluids which are expected to accumulate toward the arches of the
sills. HSG=Huronian Supergroup sediments; NG=Nipissing Gabbro; qG=quartz gabbro;
opxG=orthopyroxene gabbro; vtG=vari-textured gabbro; GG=granophyric gabbro;
AP=aplite. The cross section is based on the undulatory model for Nipissing Gabbro
intrusions (Hriskevich, 1968).
148
5.3.2 Major Element Variations
CIPW normative calculations completed on 12 of the 14 samples, show 10 of the
samples to be quartz-hypersthene-normative (silica-oversaturated) and 2 samples to be
silica-saturated hypersthene-olivine-normative (Table 5-8). Sample JB97-65 is from a
granophyric pod (Photo 4-12) and sample JB98-121B is from an alteration zone with
high S composition. The 10 silica-oversaturated samples classify mainly as CIPW
normative gabbro with subordinate leucogabbro, corresponding to the field assigned
names of gabbro, vari-textured gabbro and granophyric gabbro. The 2 silica-saturated
samples classified as CIPW normative olivine leucogabbronorite (JB97-61) and
gabbronorite (JB98-123), corresponding to the field assigned name of orthopyroxene
gabbro.
The Mg-number, coupled with Ti, may be used as a measure of the degree of
differentiation of a magma whereby decreasing Mg-number accompanied by increasing
Ti indicate increased fractionation. Figure 5-22 plots the 14 samples from the Basswood
Lake intrusion using the calculated Mg-number against wt% TiO2 along with average
chilled margin value from the present study. The least fractionated rocks (JB98-123, 124,
118 and JB97-62), which group in the region of average chilled margin, were collected
from the southern and northern quartz gabbro and orthopyroxene gabbro units. These
contrast the grouping of low Mg-number and high TiO2 rocks which were collected from
the middle region of the section, corresponding to vari-textured and granophyric gabbro.
Sample JB97-61, which has a relatively high Mg-number, is anomalous in that it has the
highest concentration of TiO2. This elevated TiO2 composition may be due to
contamination of the orthopyroxene gabbro unit as a result of AFC processes (Lightfoot
and Naldrett, 1996).
149
Photo 5-1. Basswood Lake Intrusion. (A) Aplite dike cutting medium-grained gabbro.
The hammer handle is about 30 cm long. (B) Sediment fragment in medium-grained
gabbro. The hammer handle is about 30 cm long.
150
Variation in selected major elements across the intrusion are shown in Figure 5-23,
with the major elements plotted against the relative distance through the section. The
concentration of SiO2 and TiO2, along with the variation in Mg-number can provide a
good indication of differentiation trends in magmas, with SiO2 and TiO2 increasing and
Mg-number decreasing with fractionation. Two differentiation trends are recognizable in
the plot of Mg-number; a decreasing, “normal” fractionation trend through the lower half
of the section, followed by an increasing, “reverse” trend through the upper half (Fig. 5-
23). Concentrations of SiO2 show very little variation through the section and TiO2
concentrations (not shown) are highly variable; the extreme variability in the latter is
probably due to AFC processes (Lightfoot and Naldrett, 1996). Although not apparent in
concentrations of SiO2 and TiO2, the mirroring in the Mg-number, provides some
evidence for apparent “inward” crystallization of this intrusion, which would have been
coupled with magmatic fluids migrating upward along the limbs from deeper portions of
the sill fluids, culminating toward the arch region of the sill (Fig. 5-21). Although the
geochemical evidence is not overwhelming, the field evidence and the symmetrical
distribution of the Mg# does provide some support that this section represents an exposed
antiformal or arch section of the sill (Figs. 5-20 and 5-21).
5.3.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams for the Basswood Lake
intrusion section are shown in Figure 5-24. Except for the granophyric pod sample
(JB97-65), all of the gabbroic rocks show near-parallel patterns with moderate to strong
LILE (Rb, Th, K) enrichment (~10-100 times primitive mantle) with average La/Sm ~2.5
and low to moderate HREE enrichment (~1-10 times primitive mantle). Most of the
gabbroic samples show pronounced negative Nb+Ta and P* anomalies and moderate to
weak negative (or flat) Ti* anomalies; samples JB97-64 and 66, medium- to coarse-
grained gabbro (CIPW leucogabbro), have weak positive Ti* anomalies.
151
JB97-61
JB97-66
JB98-121A
Chilled Margin Avg
0.0
0.5
1.0
1.5
2.0
2.5
3.0
102030405060708090
Mg-number
TiO
2 (w
t%)
JB98-118JB97-61JB97-62JB97-63JB97-64JB97-65JB97-66JB98-119JB98-120JB98-121AJB98-121BJB98-122JB98-123JB98-124Chilled Margin Avg
fractionation
+ aplite olivine leucogabbronorite
B leucogabbro gabbro
U gabbronorite secondary Cu-vein
Figure 5-22. Bivariate scatter plot of 14 samples from the Basswood Lake intrusion using
the calculated Mg-number and wt% TiO2; for comparison, average chilled margin gabbro
from the present study is also shown.
152
Figure 5-23. Profiles through the Basswood Lake intrusion showing stratigraphic
variations in Mg-number and SiO2. The relative vertical scale is in metres.
153
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-118JB97-61JB97-62JB97-63JB97-64JB97-66JB98-119JB98-120JB98-121AJB98-122JB98-123JB98-124Chilled Margin AvgHuronian Sediment AvgAplite Avg (PL)
olivine leucogabbronorite (CIPW)B leucogabbro (CIPW)
gabbro (CIPW)U gabbronorite (CIPW)
(B)
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-65
JB98-121B
JB97-61
Chilled Margin Avg
Huronian Sediment Avg
Aplite Avg (PL)
+ aplite olivine leucogabbronorite (CIPW) secondary Cu-vein
(D)
Figure 5-24. Primitive mantle-normalized multi-element diagrams for rock samples from the Basswood Lake intrusion. (A) Gabbroic samples. (B) Atypical profiles. Mantle normalizing values are from McDonough and Sun (1995).
154
5.3.4 Chalcophile (PGE, Cu, Ni) Element Variations
The highest measured Pt+Pd concentrations are from the southernmost and
northernmost samples which also recorded some of the highest MgO concentrations
(Table 5-8). Southern samples JB98-122, 123 and 124 range from 12.4-64.7 ppb Pt+Pd
(Pd/Pt ~1.0; Cu/Ni ~1.9) and northern samples JB98-118, JB97-62 and 63 range from
12.9-31.5 ppb Pt+Pd (Pd/Pt ~1.9; Cu/Ni ~1.9). The highest Ni concentrations also occur
in the northernmost and southern most samples ranging 104-112 ppm in the north and
109-130 ppm in the south.
Selected chalcophile elements and ratios plotted against relative distance through the
intrusion are shown in Figure 5-25. Sample JB98-121B and 121A (Photo 4-13),
considered anomalous in terms of chalcophile elements, tend to disrupt the “normal”
trend on the chemostratigraphic profiles as indicated on each of the plots. The main trend
in the S/Se ratios is similar for both the lower and upper parts of the plot, showing an
initial “inward” decrease, followed by a marked increase through the granophyric gabbro
and reaching maximum in the granophyric pod. Nearly all of the S/Se values are within
the acceptable range of uncontaminated magmatic sulphides (Naldrett, 1981), the
exception being sample JB97-65 (granophyric pod; Photo 4-12) whose S/Se value
(~6500) suggests contamination. The Cu/Ni ratio records a fractionation trend that is
similar to S/Se, with an initial “inward” decrease, followed by a marked increase through
the granophyric gabbro and granophyric pod.
A primitive mantle-normalized PGE and chalcophile element diagram (recalculated
to metals in 100% sulphide) is shown in Figure 5-26. Of the 14 samples analysed for
whole rock PGE, only one sample (JB98-123) assayed above the lower limit of detection
in all of the PGE plus Au. However, for plotting purposes, it is possible to make use of
near compete PGE data from seven of the 14 samples, assigning the average lower limit
of detection for each of the elements that were below detection limits. Patterns from four
of the seven samples are characterized by positive slopes with the Pt-Pd-Au-Cu portion
(~1000 times primitive mantle) of the trends elevated relative to the Ni-Ir-Ru-Rh portion
(~10-500 times chondrite). These samples, which include quartz gabbro, gabbro and
orthopyroxene gabbro, have patterns that are similar to that of the Portimo Dikes from
Finland (Iljina, 1994), although Pd is considerably lower in Nipissing Gabbro samples.
155
Figure 5-25a. Profiles through the Basswood Lake intrusion showing stratigraphic
variations in S/Se. The relative vertical scale is in metres.
156
Figure 5-25b. Profiles through the Basswood Lake intrusion showing stratigraphic
variations in Cu/Ni. The relative vertical scale is in metres.
157
1
10
100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-118
JB97-62
JB97-63
JB98-121A
JB98-122
JB98-123
JB98-124
Chilled Margin Avg
Flood Basalt Avg
B leucogabbro (CIPW)( gabbro (CIPW)U gabbronorite (CIPW)
JB98-121Aaltered granophyric gabbro
Figure 5-26. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from Basswood Lake intrusion
rocks. Data for average chilled margin is from this study; data for average flood basalt is
from Naldrett (1981); data for mineralized River Valley intrusion from this study. Mantle
normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
158
Contrasting these trends are two samples of granophyric gabbro (JB97-63 and JB98-122)
which display similar overall positive trends but with distinctly depleted Pd and Ni
concentrations; this depletion in Pd and Ni may be attributed to remobilization. Sample
JB98-121A, collected from an altered granophyric gabbro with about 1% disseminated
pyrite, displays elevated Ir-Ru-Rh relative to anomalously depleted Ni-Pt-Pd-Au-Cu; this
chalcophile pattern is interpreted to have resulted from the remobilization of Ni-Pt-Pd-
Au-Cu which are considered much more mobile than the Ir-Ru-Rh.
5.4 Appleby Lake Intrusion - Traverse
The Appleby Lake intrusion, located about 4.5 km northeast of the Basswood Lake
intrusion along Highway 129 in Wells Township, is a relatively narrow (~2 km wide)
body trending 330 degrees (Figs. 1-2, 5-20 and 5-27). A total of 12 samples were
collected along Highway 129, which provides a well-exposed section through the
intrusion; the section is located at about 250 m ASL. A sample summary is provided in
Table 5-9 and sample locations are shown in Figure 5-27; a full listing of the data is
provided in Appendix 1.
5.4.1 Geology and Mineralization
At surface, the Appleby Lake intrusion is separated from the Basswood Lake
intrusion, located to the southwest (Fig. 5-20), by sedimentary rocks of the Huronian
Supergroup’s Cobalt Group (Gowganda Formation); it is likely that these two bodies are
connected at depth (Fig. 5-21). Although no contacts with the hosting sedimentary rocks
are exposed in the immediate area of the section, the fine-grained to chilled quartz gabbro
from the northeast end of the section suggests that the contact is within a few metres.
From south to north, the sample suit consists of massive medium-grained gabbro grading
into coarse-grained gabbro, locally altered (pink- to red-stained) medium-grained
granophyric gabbro containing up to 10% disseminated pyrite associated with narrow
(centimetre-scale) quartz-carbonate veinlets, grading into massive medium- to coarse-
grained vari-textured gabbro and granophyric gabbro that is gradational into fine-grained
to chilled quartz gabbro (Fig. 5-27). Current geochemical and especially field evidence,
including the lack of orthopyroxene gabbro and the predominance of granophyric-aplitic
rocks, suggests that this section, as in the Basswood Lake section, represents an unroofed
and eroded antiformal arch portion of an undulating sill (Fig. 5-21).
159
Figure 5-27. General geology and sample locations from the Appleby Lake intrusion in
Wells Township. Geology modified after Ontario Geological Survey Map 2419 (1979).
160
Sample CIPW S Se Ni Ir Ru Rh Pt Pd AuNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb ppb
JB97-48 G (Q-H) 0.060 327 120 - - 0.16 11.20 13.54 3.02JB97-49 G (Q-H) 0.080 364 96 - - - - - -JB97-50 G (Q-H) 0.110 347 65 - - - - 2.06 67.76JB97-51 LG (Q-H) 0.160 345 27 - - - - - 3.41JB97-52 G (Q-H) 0.120 411 60 - - - - - 2.50JB97-53 G (Q-H) 0.100 1395 78 - - - - - 3.47
JB97-54A LG (Q-H-C) 0.930 402 35 - - - 0.16 - 76.10JB97-54B G (Q-H) 0.090 352 79 - - 0.21 - 1.76 6.29JB97-55 G (Q-H) 0.080 358 100 - - - - - 2.71JB97-56 G (Q-H) 0.070 375 110 0.59 - 0.44 4.34 3.44 3.61JB97-57 G (Q-H) 0.080 422 110 - - - 5.00 - 4.21JB97-58 G (Q-H) 0.080 402 110 - - - 7.84 8.42 8.56Sample Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppm ppmJB97-48 170 1835 1.2 1.4 56 49 1.62JB97-49 160 2198 - 1.7 52 59 1.97JB97-50 170 3170 - 2.6 41 74 1.98JB97-51 65 4638 - 2.4 25 112 2.23JB97-52 190 2920 - 3.2 36 73 1.95JB97-53 160 717 - 2.1 46 71 1.96
JB97-54A 84 23134 - 2.4 24 688 8.36JB97-54B 170 2557 - 2.2 46 67 1.83JB97-55 170 2235 - 1.7 55 52 1.86JB97-56 160 1867 0.8 1.5 57 48 1.80JB97-57 180 1896 - 1.6 54 53 1.80JB97-58 170 1990 1.1 1.5 54 52 1.76
Table 5-9. Summary of whole-rock geochemical characteristics for samples from the
Appleby Lake intrusion, Wells Township. "-" below lower limit of detection; "N" =
primitive mantle-normalized; G=gabbro; OLGN=olivine leucogabbronorite;
LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-
olivine; Q-H-C=quartz-hypersthene-corundum. Norm wt% = rock types determined on
the basis of weight percent normative minerals calculated to normative weight percent.
161
There are no known significant magmatic sulphide occurrences hosted by the
Appleby Lake intrusion. With the exception of JB97-54A (~10% visible pyrite), none of
the samples collected from the Appleby Lake section have appreciable (>1%) sulphide.
5.4.2 Major Element Variations
CIPW normative calculations completed on the 12 samples, show 11 of the 12
samples to be quartz-hypersthene normative (silica-oversaturated), with 10 classifying as
gabbro and 1 as leucogabbro (Table 5-9). Sample JB98-54A, classifying as a quartz-
hypersthene-corundum normative (silica-oversaturated) leucogabbro, was collected from
an altered granophyric gabbro with pyrite and quartz-carbonate veining. Figure 5-28, a
plot of Mg-number versus TiO2, is useful for determining the degree of fractionation in
the rock samples. The least fractionated rocks (JB97-55, 56, 57, 58), which group near
the compositional average chilled margin, were collected from the westernmost and
easternmost ends of the section, whereas the more fractionated rocks (JB97-50, 51, 52,
53, 54B) are from the middle region of the section, corresponding to dominantly vari-
textured and granophyric rocks. Weak, “inward” directed fractionation pattern is
interpreted from the geochemical data, similar to that from the Basswood Lake intrusion
(see Section 5.3), and as reported from other Nipissing Gabbro intrusions (e.g. Conrod,
1988; Lightfoot and Naldrett, 1996).
Variation in Mg-number and SiO2 are shown in Figure 5-29, plotted against relative
distance through the section; as in the Basswood Lake intrusion, the concentration of
TiO2 is highly variable (not shown) and SiO2 is reasonably uniform, probably as a result
of AFC processes (Lightfoot and Naldrett, 1996). The Mg-number shows a weakly
developed “inward” directed fractionation trend, with mirroring in the Mg-number from
the top and bottom, toward the central region of the section. As in the Basswood Lake
intrusion, the geochemical evidence is not overwhelming, but the field evidence does
support the interpretation that this section represents an exposed upper portion of a sill
(Fig. 5-21).
5.4.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams for the gabbroic rocks
collected from the Appleby Lake section are shown in Figure 5-30.
162
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1.0
1.5
2.0
2.5
102030405060708090
Mg-number
TiO
2 (w
t%)
JB97-48JB97-49JB97-50JB97-51JB97-52JB97-53JB97-54AJB97-54BJB97-55JB97-56JB97-57JB97-58Chilled Margin Avg
fractionation
Ychilled gabbro (gabbro - CIPW)B leucogabbro (CIPW)A gabbro (CIPW)
JB97-54Aaltered granophyric gabbro(~10% pyrite)
Figure 5-28. Bivariate scatter plot of samples from the Appleby Lake intrusion using the
calculated Mg-number and wt% TiO2; for comparison, average chilled margin gabbro
from the present study is also shown.
163
Figure 5-29. Profile through the Appleby Lake intrusion showing stratigraphic variations
in Mg-number and SiO2. The relative vertical scale is in metres.
164
All of the gabbroic samples, except JB97-54A (altered granophyric gabbro), show near-
parallel patterns that are similar but elevated relative to average chilled margin, with
moderate to strong LILE enrichment (~10-100 times primitive mantle; average La/Sm
~1.9) and low to moderate HREE enrichment (~1-10 times primitive mantle). As is
typical of Nipissing Gabbro rocks, all of these samples show pronounced negative Nb+Ta
and P* anomalies and subtle negative to flat (slightly positive) Ti* anomalies.
5.4.4 Chalcophile (PGE, Cu, Ni) Element Variations
Individual PGE concentrations for most samples were mostly near or below the
lower limits of detection. The highest concentration of Pt+Pd (24.74 ppb; Pd/Pt = 1.2;
Cu/Ni = 1.4) is from chilled quartz gabbro (JB97-48), followed by gabbro samples JB97-
56 (7.78 ppb; Pd/Pt = 0.8; Cu/Ni = 1.5) and JB97-58 (16.26 ppb; Pd/Pt = 1.1; Cu/Ni =
1.6); these samples are from the southernmost and northernmost parts of the sample
section.
Selected chalcophile elements and ratios, plotted against relative distance through the
Appleby section, are shown in Figure 5-31. The plot of S/Se shows a subtle “inward”
increase, from both the upper and lower parts of the section toward the middle where
there is a sudden decrease in S/Se (717; JB97-53) in the vari-textured/granophyric gabbro
unit (JB97-53), suggesting sulphur loss (Reeves and Keays, 1995). Excepting samples
JB97-53 and JB97-54A, all of the S/Se values plot within the acceptable range (~1835-
4638) of uncontaminated magmatic sulphide (Naldrett, 1981). Sample JB97-54A yields
a contamination signature for S/Se (23,134), suggestive of contamination by external
sedimentary-derived sulphur (Naldrett, 1981). The ratio of Cu/Ni records an “inward”
increasing fractionation trend.
A primitive mantle-normalized PGE and chalcophile element diagram (recalculated
to metals in 100% sulphide) is shown in Figure 5-32. Of the 12 samples analyzed for
whole rock PGE, only one sample (JB97-56) assayed above the lower limits of detection
for 4 (Ir, Rh, Pt, Pd) of the 5 PGE; an average lower limit of detection value (0.66 ppb)
was allocated to Ru. This sample, a classified as a gabbro (both in the field and by
CIPW) is characterized by a moderate positive PGE slope (Pt-Pd-Au-Cu > Ni-Ir-Ru-Rh)
that is close to that of average chilled margin gabbro but more significantly, it is similar
to the trend of average continental flood basalt.
165
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1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-48
JB97-49JB97-50
JB97-51JB97-52
JB97-53JB97-54B
JB97-55JB97-56JB97-57
JB97-58Chilled Margin Avg
(A)Y chilled gabbro (gabbro - CIPW)B leucogabbro (CIPW)A gabbro (CIPW)
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-54A
Chilled Margin Avg
Huronian Sediment Avg
Aplite Avg (PL)
JB97-54Aaltered granophyric gabbro(~10% pyrite)
B leucogabbro (CIPW)(B)
Figure 5-30. Primitive mantle-normalized multi-element diagrams for rock samples from the Appleby Lake intrusion. (A) Gabbroic samples. (B) Atypical profiles. Mantle normalizing values are from McDonough and Sun (1995).
166
Figure 5-31a. Profiles through the Appleby Lake intrusion showing stratigraphic
variations in S/Se. The relative vertical scale is in metres.
167
Figure 5-31b. Profiles through the Appleby Lake intrusion showing stratigraphic
variations in Cu/Ni. The relative vertical scale is in metres.
168
1
10
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10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB97-56
Chilled Margin Avg
Flood Basalt Avg
A gabbro (CIPW)
Figure 5-32. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from the Appleby Lake intrusion
rocks. Data for average chilled margin is from this study; data for average flood basalt is
from Naldrett (1981). Mantle normalizing values are from Barnes et al. (1988) and
McDonough and Sun (1995).
169
5.5 Charlton Lake Intrusion - Traverse
The Charlton Lake intrusion, located about 65 km southwest of the City of Greater
Sudbury and ~3 km north of the village of Whitefish Falls (Figs. 1-2 and 5-33), extends
for more than 16 km across Mongowin and Curtin townships (Card, 1976). The sample
suite, consisting of 13 samples, was collected from an elevated and relatively well-
exposed section of Nipissing Gabbro along the northeastern shoreline of Charlton Lake
(Fig. 5-33). The section, which is about 320 m wide, exposes gabbroic rocks and the
footwall and hangingwall Huronian sedimentary rocks. A summary of the samples is
provided in Table 5-10 and a complete listing of the data is provided in Appendix 1.
5.5.1 Geology and Mineralization
Phemister (1939) suggested that the Charlton Lake intrusion is a sill and current
geochemical and field evidence from the Charlton Lake section supports this
interpretation; the northern contact representing the base of the sill and the southern
margin, the top. In the area of the sample section, the Charlton Lake intrusion is hosted
by Gowganda Formation sedimentary rocks (conglomerate, siltstone, argillite). The
southern contact, interpreted to represent the hangingwall, is partially exposed and
consists primarily of sedimentary-gabbro breccia with fragments of sedimentary rock
10’s of centimetres in size. The contact itself is sharp and irregular, marked by very fine-
grained (chilled) gabbro and altered (bleached) sedimentary rocks; the northern contact
region, interpreted as the footwall, is not exposed. Several percent visible sulphide were
noted from gabbro (JB98-183) and orthopyroxene gabbro (JB98-182), situated about 80
m south of the northern contact (Fig. 5-33).
From north to south, the sample suite comprises massive medium-grained gabbro
which is gradational into massive medium-grained orthopyroxene gabbro, which is in
turn gradational into massive medium-grained to locally coarse-grained gabbro, and
finally fine-grained gabbro. Sample JB98-186, located along the section between
samples JB98-184 and 183, was collected from a felsic dike which cut through the
gabbro.
A number of PGE-Cu-Ni sulphide occurrences are known to be hosted by this
intrusion (Fig. 5-40), concentrated in the area from Upsala Gold Mine to Casson Lake
(~6.5 km long), and including the AN3 showing (see Section 5.6).
170 170
171
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB98-185 sediment 0.085 160 20 0.013 0.680 0.115 0.440 0.518JB98-184 GN (H-O) 0.035 241 175 0.070 0.500 0.663 13.980 55.500JB98-183 GN (H-O) 0.232 1733 511 0.267 0.640 1.820 58.000 156.000JB98-182 GN (H-O) 0.085 422 166 - 0.270 0.126 3.150 3.010JB98-181 G (Q-H) 0.078 364 98 - 0.320 0.480 0.238 0.282JB98-180 G (Q-H) 0.076 234 131 - - - 1.780 1.470JB98-179 G (Q-H) 0.070 366 148 - 0.370 0.092 1.677 1.750JB98-178 G (Q-H) 0.031 155 118 - 0.150 - 1.570 1.830JB98-177 G (Q-H) 0.017 105 83 - 0.190 - 1.320 1.190JB98-175 G (Q-H) 0.034 191 120 - 0.160 0.202 8.600 7.110JB98-174 GN (H-O) 0.285 1036 139 - - 0.320 8.790 10.560JB98-176 sediment 0.005 13 16 0.010 0.150 0.019 0.298 0.142JB98-186 felsic dike 0.005 24 15 0.040 0.044 0.017 0.234 0.399Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB98-185 1.830 11 5313 1.2 0.6 40 120 4.14JB98-184 4.510 120 1452 4.0 0.7 74 30 2.04JB98-183 33.500 870 1339 2.7 1.7 74 28 2.05JB98-182 2.350 295 2014 1.0 1.8 71 31 1.95JB98-181 1.630 143 2143 1.2 1.5 66 39 2.33JB98-180 1.940 161 3248 0.8 1.2 71 33 2.11JB98-179 2.230 221 1913 1.0 1.5 70 39 2.34JB98-178 2.560 86 2000 1.2 0.7 65 42 2.37JB98-177 1.890 154 1619 0.9 1.9 62 60 2.52JB98-175 3.040 104 1780 0.8 0.9 69 29 1.97JB98-174 13.200 412 2751 1.2 3.0 63 42 2.20JB98-176 1.650 9 3846 0.5 0.6 50 63 3.29JB98-186 0.575 3 2083 1.7 0.2 61 12 1.52
Table 5-10. Summary of whole-rock geochemical characteristics for samples from the
Charlton Lake intrusion, Curtin Township. "-" below lower limit of detection; "N" =
primitive mantle-normalized; G=gabbro; OLGN=olivine leucogabbronorite;
LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-
olivine; Q-H-C=quartz-hypersthene-corundum. Norm wt% = rock types determined on
the basis of weight percent normative minerals calculated to normative weight percent.
172
The dominant style of mineralization is sulphide associated PGE (~1-3% disseminated
chalcopyrite and pyrrhotite) with average values of 0.5-1.5 g/t Pd and 0.25-1.0 g/t Pt,
exposed over widths of 5-30 m (Harron, 2000). A second style of PGE mineralization is
described as cross-cutting, “volatile enriched” hydrothermal mineralization, associated
with elevated chromite, chalcopyrite and pyrrhotite with values up to 8 g/t Pd and 3 g/t Pt
(Harron, 2000). Several Au occurrences (quartz-vein, structurally controlled, and/or
sediment hosted) are also known to occur at or proximal to the contact between the
Nipissing Gabbro intrusion and the hosting sedimentary rocks (Card, 1976).
5.5.2 Major Element Variations
On the basis of 12 CIPW normative calculations (Table 5-10), 4 of the samples are
hypersthene-olivine-normative (silica-saturated) and classify as gabbronorite, and
correspond with assigned field names of gabbro and orthopyroxene gabbro. The
remaining 8 samples are quartz-hypersthene-normative (silica oversaturated) and classify
as gabbro, corresponding with their gabbro field names.
All of the gabbroic samples plot with higher Mg-number and lower concentrations of
TiO2, relative to average chilled margin gabbro (Fig. 5-34). Assuming that average
chilled margin is representative of parent magma composition, it follows that these higher
MgO and lower TiO2 concentrations reflect higher proportions of orthopyroxene
phenocrysts and/or olivine in these rocks. Variation in selected major elements across the
intrusion are shown in Figure 5-35, plotting major elements against relative distance
through the intrusion from the base (north end) to the upper contact (south end). The
concentration of SiO2 shows subtle variation and only a very slight increase “upward”
through the intrusion, from north to south. The concentration of TiO2 shows a strong
positive fractionation trend increasing from ~0.4 wt% near the base to >0.5 wt% toward
the top. Decreasing Mg-number, characteristic of normal magma differentiation, is
evident from north to south across the intrusion with the highest Mg-numbers in the
lowermost orthopyroxene gabbro (CIPW gabbronorite). Sample JB98-177, which
disrupts the general trends on all of the chemostratigraphic plots, was collected from very
near (~5 m) the contact with Huronian sedimentary rocks (sample JB98-176). Its
uncharacteristic chemistry, including elevated SiO2 and TiO2, suggests contamination,
most probably through interaction with hangingwall Huronian sediment.
173
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0.5
0.6
0.7
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Mg-number
TiO
2 (w
t%)
JB98-176 (HW)JB98-174JB98-175JB98-177JB98-178JB98-179JB98-180JB98-181JB98-182JB98-183JB98-186JB98-184JB98-185 (FW)Chilled Margin Avg
+ sedimentA gabbro (CIPW)U gabbronorite (CIPW)# felsic dike
fractionation
Figure 5-34. Bivariate scatter plot of samples from the Charlton Lake intrusion using the
calculated Mg-number and wt% TiO2; for comparison, average chilled margin gabbro
from the present study is also shown.
174
Figure 5-35a. Profiles through the Charlton Lake intrusion showing stratigraphic
variations in Mg-number and SiO2. The relative vertical scale is in metres.
175
Figure 5-35b. Profiles through the Charlton Lake intrusion showing stratigraphic
variations in TiO2. The relative vertical scale is in metres.
176
5.5.3 Trace and Rare-Earth Element Variations
Variations in Zr and ∑REE plotted against relative distance through the sample
section are shown in Figure 5-36. This chemostratigraphic plot shows a gradual increase
through the intrusion, suggesting normal fractionation from north to south. As was seen
in the major element plots, sample JB98-177 plots outside of the general trend, which is
probably the result of contamination through interaction with hangingwall sedimentary
rocks.
Primitive mantle-normalized multi-element diagrams for the Charlton Lake section
are shown in Figure 5-37. Gabbroic rocks show near-parallel patterns, following closely
the pattern of average chilled margin gabbro, with moderate to strong LILE enrichment
(~10-100 times primitive mantle), an average of ~2.7 La/Sm, and low to moderate HREE
enrichment (~1-10 times primitive mantle). All of the gabbroic samples show
pronounced negative Nb+Ta, P* and Ti* anomalies, a typical feature of Nipissing
Gabbro magmas. The felsic dike (JB98-186) displays the widest variance in trace and
rare-earth elements with anomalously high Th, P* and Zr concentrations and
anomalously low Rb and K* concentrations. These variations suggest that this dike may
be genetically linked to the immediate Huronian sedimentary rocks and may represent
sedimentary derived melt that was sourced from the footwall sedimentary rocks and
“back-injected” into the gabbro.
5.5.4 Chalcophile (PGE, Cu, Ni) Element Variations
Within the section sample suite, sulphide occurs in samples JB98-183, collected
from the lowermost gabbro unit, and sample JB98-174, collected from the gabbro unit
proximal to the hangingwall Huronian sediment; as indicated earlier, sample JB98-174
has geochemical signatures indicative of contamination. The sulphides (~1%) are
primarily finely disseminated chalcopyrite and pyrrhotite with subordinate pyrite. The
highest concentrations of Pt+Pd are from samples JB98-183 (~214 ppb Pt+Pd; Pd/Pt
~2.7; Cu/Ni ~1.7) and JB98-184 (~70 ppb Pt+Pd; Pd/Pt ~4.0; Cu/Ni ~0.7) in the
lowermost gabbro (CIPW gabbronorite) and from samples JB98-174 (~19 ppb Pt+Pd;
Pd/Pt ~1.2; Cu/Ni ~3.0) and JB98-175 (~16 ppb Pt+Pd; Pd/Pt ~0.8; Cu/Ni ~0.9) in the
uppermost gabbro.
177
Figure 5-36. Profile through the Charlton Lake intrusion showing stratigraphic variations
in Zr and total rare-earth elements. The relative vertical scale is in metres.
178
0.1
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100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-174
JB98-175
JB98-177
JB98-178
JB98-179
JB98-180
JB98-181
JB98-182
JB98-183
JB98-184
Chilled Margin Avg
+ sedimentA gabbro (CIPW)) gabbronorite (CIPW)
(A)
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-174
JB98-177
JB98-186
Chilled Margin Avg
A gabbro (CIPW)) gabbronorite (CIPW)# felsic dike
(B)
Figure 5-37. Primitive mantle-normalized multi-element diagrams for rock samples from the Charlton Lake intrusion. (A) Gabbroic samples. (B) Atypical profiles. Mantle normalizing values are from McDonough and Sun (1995).
179
Selected chalcophile elements and ratios are plotted against relative distance through
the intrusion in Figure 5-38. The highest S/Se values are from the hangingwall and
footwall sedimentary rocks (3846 and 5313), contrasting the lower S/Se values from the
intrusive rocks which are between 1339 and 3248. The S/Se ratios of the gabbroic rocks
are all within the range of uncontaminated magmatic sulphide (Naldrett, 1981).
Concentrations of S show a general decline from the lowermost gabbro unit (CIPW
gabbronorite) upward or southward into the upper part of the middle gabbro unit, then
increasing toward a maximum S concentration in the upper gabbro (CIPW gabbronorite)
unit. The S maxima from the upper and lower gabbro (CIPW gabbronorite) units are
coincident with the 2 maximum values of Pt+Pd and Cu, suggesting sulphide control on
the PGE.
The ratio of Cu/Pd has been shown to be a useful indicator of whether or not
sulphide segregation has occurred within a magma (Hamlyn et al., 1985; Hoatson and
Keays, 1989). Rocks with Cu/Pd values above 6500 indicate that they may have
crystallized from magma that has lost Pd as a result of earlier sulphide segregation,
whereas magmas with Cu/Pd values below 6500 should contain Pd-rich sulphides. This
ratio is also useful when scrutinizing chemostratigraphic sections, whereby a distinct
increase in the Cu/Pd ratio occurs in the vicinity of PGE-rich horizons (Prendergast and
Keays, 1989; Hoatson and Keays, 1989; Barnes et al., 1992; Maier et al., 1996). In
Figure 5-38a, values of Cu/Pd are <6500 for the first 2 samples in the lowermost gabbro
unit, but quickly jump to ~98,000 and remain above 14,000 for the remainder of the
stratigraphy. This sudden change in the lowermost orthopyroxene gabbro unit suggests
that S-saturation occurred at this point in the stratigraphy.
Reeves and Keays (1995), in their study of the Bucknalla Complex (Australia),
demonstrated that first formed sulphides (precipitating from high Mg, S-undersaturated
magmas) have higher relative Pd/S and Pt/S, which decrease as PGE supply is reduced
and S continues to increase during normal progressive fractionation. The instance of S-
saturation is reflected by the chemostratigraphic plot of Pt/S and Pd/S (Fig. 5-38b) where
the rapid decrease in Pt/S and Pd/S ratios correlate with the rapid increase in Cu/Pd at
sample JB98-182.
180
0
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30
40
50
60
70
80
90
100
1 10 100 1000 10000 100000 1000000
Concentrations and Ratios
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
orthopyroxene gabbro (GN)
gabbro (GN)
gabbro (G)
sediment
gabbro (GN)
NORTH
SOUTH
S/Se Cu/PdS (ppm)
(A)
Figure 5-38a. Profiles through the Charlton Lake intrusion showing stratigraphic
variations in S, S/Se and Cu/Pd. The arrows indicate the direction of sulphide
precipitation (crystallization) fronts. The relative vertical scale is in metres.
181
0
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30
40
50
60
70
80
90
100
0.1 1 10 100 1000 10000
Concentrations and Ratios
Rel
ativ
e D
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nce
(not
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ale)
sediment
orthopyroxene gabbro (GN)
gabbro (GN)
gabbro (G)
sediment
gabbro (GN)
NORTH
SOUTH(B)
Pt+Pd (ppb)Cu/Ni Pd/Pt Pt/S Pd/S
Figure 5-38b. Profiles through the Charlton Lake intrusion showing stratigraphic
variations in Cu/Ni, Pd/Pt, Pt+Pd, Pt/S and Pd/S. The arrows indicate the direction of
sulphide precipitation (crystallization) fronts. The relative vertical scale is in metres.
182
Another trend exhibited by the Pt/S and Pd/S ratios is declining ratios from the top
(south) and base (north) of the intrusion toward the central area of the section. This
suggests that there was co-precipitation of sulphides in the magma along two sulphide
precipitation fronts; one moving downward from the upper part of the sill and the other
moving upward from the lower part of the sill. This is also reflected in the Cu/Pd ratio
which exhibits increasing Cu/Pd from the base upward and from the roof downward; this
trend is weakly reflected in the variation of Mg-number (Fig. 5-35).
Primitive mantle-normalized PGE and chalcophile element diagrams (recalculated to
metals in 100% sulphide) are provided in Figure 5-39. Of the 13 samples analysed for
whole rock PGE, only five of the samples assayed above the lower limits of detection in
all of the PGE plus Au. However, it is possible to make use of near complete PGE data
from nine of the 13 samples, assigning the average lower limit of detection for each of
the elements that were below detection limits. Excepting samples JB98-181 (gabbro) and
JB98-185 (footwall sediment), all of the samples (two sedimentary rocks, six gabbroic
rocks and one felsic dike) are characterized by positive slopes in the PGE patterns (Pt-Pd-
Au-Cu > Ni-Ir-Ru-Rh). Samples JB98-184 and JB98-183, located at the level in the
intrusion before which S-saturation is thought to have occurred, have the highest
concentrations of Rh-Pt-Pd-Au-Cu, reflecting the change in magma composition at S-
saturation.
The unusual pattern exhibited by JB98-181 (Fig. 5-39), characterized by
anomalously depleted Pt-Pd relative to Ir-Ru-Rh, is interpreted to be the result of
hydrothermal redistribution of Pt and Pd. PGE patterns from the 2 sedimentary rock
samples are similar, although the abundance of PGE in the hangingwall sedimentary rock
sample is about 10 times higher than the footwall sedimentary rock sample. The felsic
dike sample (JB98-186) has a distinct profile but plots within the range of the gabbroic
and sedimentary samples.
183
1
10
100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-176 (HW)JB98-175JB98-179JB98-181JB98-182JB98-183JB98-186JB98-184JB98-185 (FW)Chilled Margin AvgFlood Basalt Avg
JB98-181
+ sedimentA gabbro (CIPW)) gabbronorite (CIPW)# felsic dike
(A)
Figure 5-39. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from the Charlton Lake intrusion
rocks. Data for average chilled margin is from this study; data for average flood basalt is
from Naldrett (1981). Mantle normalizing values are from Barnes et al. (1988) and
McDonough and Sun (1995).
184
5.6 AN3 Occurrence and Traverse
The AN3 PGE-Cu-Ni occurrence, located about 9.5 km east of the Charlton Lake
section (see Section 5.5) and south of Casson Lake (Figs. 1-2, 5-40 and 5-41), is hosted
by the Charlton Lake sill (see Section 5.5). The sample suite, consisting of 5 samples,
was collected along a north-south section through the Nipissing Gabbro sill, about 100 m
east of the AN3 PGE-Cu-Ni occurrence and several hundred metres west of 3 other
cleared areas (AN1 AN2, AN4) that also contain anomalous PGE-Cu-Ni (Fig. 5-41).
One sample, JB98-225A, was collected from the location of the “malachite pit”, about
400 m east of the sample section. A summary of the rock samples is provided in Table 5-
11 and a complete listing of the data is provided in Appendix 1.
5.6.1 Geology and Mineralization
The Charlton Lake sill is hosted by Gowganda Formation (Huronian Supergroup)
sedimentary rocks all along its length, from the Charlton Lake section (see Section 5.5)
and eastward through the area of the AN3 occurrence (Fig. 5-40 and 5-41). Several
northwest-trending faults and Sudbury Swarm dikes dissect the intrusion along its length;
displacement along the faults appears to be predominantly strike-slip and on the order of
10’s of metres to a few hundred metres. Numerous outcrops (mainly sedimentary rocks)
in the area contain Sudbury-type breccia (Card, 1976) and Harron (2000) described a
southeast-trending body of Sudbury-type breccia that dissects the sill in the area between
the Upsala and Bousquet Au mines. Locally, the sample section consists of
unmineralized, medium-grained, massive gabbro; neither the north or south contacts with
sedimentary rocks are exposed.
Numerous PGE-Cu-Ni sulphide showings occur along the length of the Charlton
Lake sill and the approximate locations of these are shown in Figure 5-40. A listing of
the highest concentrations of PGE-Au-Cu-Ni are provide in Table 5-12. Sample JB98-
225A, collected from the “malachite pit” (Fig. 5-41) as a example of sulphide
mineralization in the area, is described as a medium-grained gabbro containing ~5%
disseminated sulphide. At this showing, malachite staining is common along fracture
planes in the host gabbro.
In the immediate area of the sample section are the 4 PGE-Cu-Ni showings, AN1,
AN2, AN3 and AN4 (Fig. 5-41) but none of the samples collected from the sample
185
section have any significant sulphide mineralization. Sulphide mineralization at the AN3
occurrence consists of about 2-3% finely disseminated chalcopyrite and pyrrhotite,
hosted by medium-grained vari-textured gabbro with patches of pegmatitic gabbro (Photo
5-2). The sulphide-hosting vari-textured gabbro unit is locally extensively altered with
fibrous fine-grained actinolite-tremolite and chlorite and saussurite (plagioclase).
Exposed contacts between the vari-textured gabbro and surrounding Nipissing Gabbro
rocks to the west and east are sharp (Photo 5-2a), suggesting a pipe-like geometry for the
vari-textured unit.
Harron (2000), drawing on analogies to the UG-2 Reef in the Bushveld Complex,
described this unit as a pegmatoidal layer, 10 m wide (east-west) and up to 30 m thick
(north-south) and in contact with a Cr-rich (1300-5100 ppm Cr) ultramafic unit which is
overlain by a unit of massive actinolite-tremolite (altered gabbro-melagabbro?,
ultramafic?). The continuation of this unit to the east, into the area of the sample section,
was not observed in the field suggesting that this PGE-Cu-Ni occurrence is either a
sulphide showing of limited horizontal or vertical extent, or is a pipe-like structure with
potential for vertical continuation; limited diamond drilling under the AN3 showing in
1996 failed to intersect significant mineralization.
5.6.2 Major Element Variations
The 4 gabbroic samples are characterized by averages of 49.9 wt% SiO2 (range
49.47-51.16), 0.37 wt% TiO2 (range 0.35-0.40), 10.8 wt% MgO (range 10.46-11.04), and
Mg-number 75 (range 72-76). CIPW calculations on the gabbroic samples classify 3 of
the 4 as hypersthene-olivine-normative (silica-saturated) gabbronorite and one as a
quartz-hypersthene (silica-oversaturated) gabbro (Table 5-11). From north to south, there
is a general increase in the concentrations of SiO2 (49.51 to 51.16) and TiO2 (0.37 to
0.40), and a general decrease in Mg-number (76 to 72). These data suggest that the base
of the sill lies to the north. The rocks from the AN3 section have similar major-element
compositions as those from the Charlton Lake section (see Section 5.5) with higher Mg-
number and MgO concentrations and lower TiO2 concentrations relative to average
chilled margin gabbro.
186
187
188
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB98-228 GN (H-O) 0.009 113.0 166 0.147 0.28 0.91 21.50 46.50JB98-229 GN (H-O) 0.015 153.0 172 0.116 0.26 0.86 17.18 63.80JB98-230 GN (H-O) 0.045 318.0 198 0.114 0.25 0.57 33.40 42.30JB98-231 G (Q-H) 0.044 314.0 155 0.045 - 0.22 9.67 9.44JB98-232 sediment 0.039 84.0 15 0.019 0.05 0.03 0.49 0.51
Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppm
JB98-228 5.500 69 796 2.2 0.4 76 23 1.79JB98-229 4.570 90 980 3.7 0.5 75 24 1.78JB98-230 15.300 176 1415 1.3 0.9 76 23 1.85JB98-231 4.790 108 1401 1.0 0.7 72 25 2.11JB98-232 1.520 14 4643 1.0 0.9 37 86 3.45
Table 5-11. Summary of whole-rock geochemical characteristics for samples from the
AN3 sample section south of Casson Lake, Charlton Lake intrusion, Curtin Township. "-
" below lower limit of detection; "N" = primitive mantle-normalized; G=gabbro;
OLGN=olivine leucogabbronorite; LG=leucogabbro; GN=gabbronorite; Q-H=quartz-
hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-hypersthene-corundum. Norm
wt% = rock types determined on the basis of weight percent normative minerals
calculated to normative weight percent.
189
5.6.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams for the AN3 section are shown
in Figure 5-42. The gabbroic samples have profiles that are typical of Nipissing Gabbro,
with moderate to strong LILE enrichment and pronounced negative Nb+Ta and P*
anomalies; 3 of the 4 samples have weak to moderate Ti* anomalies, with one sample
(JB98-231) showing a slightly positive Ti* anomaly. Ratios in primitive mantle-
normalized (La/Sm)N range from 1.79 in the north to 2.11 in the south, suggesting little if
any crustal contamination and fractionation from north to south.
Location Pd Pt Au Cu Ni Pt+Pd Pd/Pt Cu/Nippm ppm ppm wt% wt% ppm
AN2 2.60 0.50 0.80 0.70 0.26 3.10 5.20 2.69AN3 4.50 3.40 0.90 0.30 0.12 7.90 1.32 2.50AN4 2.20 0.50 0.40 0.60 0.25 2.70 4.40 2.40BP-1 1.40 1.10 4.40 0.40 0.08 2.50 1.27 5.00BP-5 2.10 0.80 0.30 0.90 0.09 2.90 2.63 10.00BP-6 2.40 0.50 0.80 0.70 0.17 2.90 4.80 4.12BP-7 3.50 0.70 0.70 0.30 0.06 4.20 5.00 5.00BP-8 0.70 0.50 0.40 0.40 0.14 1.20 1.40 2.86BP-9 0.90 0.80 0.70 0.30 0.07 1.70 1.13 4.29
BP-10 2.10 0.50 0.90 0.80 0.28 2.60 4.20 2.86BP-11 0.30 0.20 0.10 0.40 0.13 0.50 1.50 3.08BP-12 1.40 0.30 0.60 0.40 0.22 1.70 4.67 1.82
Table 5-12. Summary of the highest concentrations of PGE-Au-Cu-Ni from historical
sampling of the Charlton Lake sill, Curtin Township. Data are reported by MacDonald
Mines Exploration Limited and summarized from Harron (2000). Data from Harron
(2000) and MacDonald Mines Exploration Ltd. (2000).
190
Photo 5-2. Charlton Lake Intrusion, Casson Lake AN3 occurrence. (A) Medium-grained massive gabbro-orthopyroxene gabbro hosting distinct “pipe-like” unit of sulphide (PGE) bearing vari-textured gabbro. Note the irregular nature of the contact. The marker pen is about 14 cm long. (B) Close up of sulphide-bearing vari-textured gabbro as in (A). The Canadian two dollar coin is about 2.8 cm in diameter.
191
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-228
JB98-229
JB98-230
JB98-231
JB98-232
Chilled Margin Avg
Aplite Avg (PL)
Huronian Sediment Avg
A gabbro (CIPW)) gabbronorite (CIPW)+ sediment
(A)
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-228
JB98-229
JB98-230
JB98-231
Chilled Margin Avg
A gabbro (CIPW)) gabbronorite (CIPW)
(B)
Figure 5-42. Primitive mantle-normalized multi-element diagrams for rock samples from the AN3 sample section. (A) All samples. (B) Gabbroic samples. Mantle normalizing values are from McDonough and Sun (1995).
192
5.6.4 Chalcophile (PGE, Cu, Ni) Element Variations
Sample JB98-225A, the only sulphide-bearing sample collected from this area, is
characterized by 1.02 ppb Ir, 1.56 ppb Ru, 5.5 ppb Rh, 264 ppb Pt, 384 ppb Pd, 166 ppb
Au, 2863 ppm Cu, 1447 ppm Ni, 1.5 Pd/Pt, and 2.0 Cu/Ni, and a magmatic S/Se value of
3667. Samples collected along the AN3 section contain no visible sulphide with S
compositions from all samples <0.05 wt% S. The highest concentration of PGE from the
sample section is from JB98-229 which contains 81.0 ppb Pt+Pd (3.7 Pd/Pt; 0.5 Cu/Ni).
Selected chalcophile elements and ratios are plotted against relative distance through
the sample section in Figure 5-43; the approximate stratigraphic level of the AN3
sulphide mineralization, located about 100 m to the west, is also shown. Two of the 4
samples have S/Se values that are within the range of magmatic sulphides (Naldrett,
1981) and two of the samples have values that are <1000, suggesting S-loss or elevated
Se relative to S. Concentrations of Pt, Pd, Cu and Ni show a decline after reaching
maxima at the projected stratigraphic level of AN3 mineralization (Fig. 5-43).
Conversely, concentrations of S and ratios of S/Se and Cu/Pd show an increase upward
through the section. The Cu/Pd ratio surpasses 6500 in the rock sample immediately
above the estimated stratigraphic level of the AN3 mineralization, suggesting that
sulphide segregation is concentrated at the stratigraphic level coincident with AN3
mineralization.
Primitive mantle-normalized PGE and chalcophile element diagrams (recalculated to
metals in 100% sulphide) are provided in Figure 5-44, with compositions from the
sample section rocks compared with average chilled margin gabbro (this study), average
flood basalt (Naldrett, 1981) and average hydrothermal mineralization from the East Bull
Lake intrusion (Peck et al., 1993b). All of the samples display positive PGE slopes with
the highest Pd abundances from 3 of the 4 gabbroic samples. These patterns are typical
of magmatic sulphide patterns and are unlike the pattern exhibited by hydrothermal
mineralization.
193
0
25
50
75
100
125
150
0.001 0.01 0.1 1 10 100 1000 10000 100000
concentration - ratio
Rel
ativ
e D
ista
nce
(m)
NORTH (FW)
SOUTH (HW)
sediment
gabbro (GN)
gabbro (G)
S/Se
Pd/SePt/Se
Cu (ppm)
Ni (ppm)
S (ppm)
approx. stratigraphic levelof AN3 mineralization
Cu/Pd
Pt (ppb)Pd (ppb)
Figure 5-43. Profiles through the AN3 sample section, showing stratigraphic variations in
Pt/Se, Pd/Se, Pt, Pd, Cu, Ni, S, S/Se and Cu/Pd. The vertical scale is relative.
194
1
10
100
1000
10000
100000
1000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-228
JB98-229
JB98-230
JB98-231
JB98-232
Chilled Margin Avg
Flood Basalt Avg
EBL Hydrothermal Avg
A gabbro (CIPW)) gabbronorite (CIPW)+ sediment
Figure 5-44. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from the AN3 section, located
south of Casson Lake, in the Charlton Lake intrusion, Curtin Township. Data for average
chilled margin is from this study; data for average flood basalt is from Naldrett (1981);
data for average East Bull Lake hydrothermal sulphide mineralization is from Peck et al.
(1993b). Mantle normalizing values are from Barnes et al. (1988) and McDonough and
Sun (1995).
195
5.7 Bell Lake Intrusion - Traverse
The Bell Lake intrusion is located in the northwest corner of Lorne Township, about
35 km southwest of the City of Greater Sudbury (Figs. 1-2 and 5-45). The sample suite
consists of 8 samples (JB98-145 to 151), collected along an ~425 m long traverse that
extends from the edge of Bell Lake northwest to within about 50 m of the CPR railway
tracks (Fig. 5-45). A summary of the samples is provided in Table 5-13 and a complete
listing of the data is provided in Appendix 1.
5.7.1 Geology and Mineralization
The Bell Lake intrusion is a relatively long body of Nipissing Gabbro that extends
for more than 10 km toward the southwest through Nairn Township (Ginn, 1965);
northwest-trending faults and Sudbury Dike Swarm dikes dissect the intrusion along its
length (Fig. 5-45). Ginn (1965) described the intrusion as a sill, emplaced concordantly
into Huronian sedimentary rocks. Although equivocal, current geochemical data suggests
that the lower portion of the sill is located to the south, along the north edge of Bell Lake.
The Bell Lake intrusion is sub-parallel to the Murray Fault Zone, which cuts off and
displaces the northeastern portion of the sill as it trends northeastward into Drury
Township. The Wright showing, from which several samples were collected, is located
about 3.75 km toward the southwest in Nairn Township, and is situated within the same
intrusion as the Bell Lake sample section (Fig. 1-2).
Locally, the Bell Lake section exposes gabbroic rocks, hosted by McKim Formation
argillite of the Elliot Lake Group (Fig. 5-45). Contacts between the Huronian sediments
and Nipissing Gabbro are not exposed in the immediate area of the section. From south
to north, the intrusive rocks comprise massive medium-grained quartz gabbro, collected
from within ~50 m of the southern contact, followed by massive fine- to medium-grained
orthopyroxene gabbro, and finally a homogenous unit of massive fine- to medium-
grained gabbro. The final samples along the section (JB98-151A and 151C) were
collected along a northwest ridge overlooking an old pit to the north that contains
sulphide mineralization in heavily gossaned Nipissing Gabbro (Photo 5-3); this pit was
sunk along the contact of the Nipissing Gabbro and Huronian sediments and is believed
to be the sulphide showing described by Ginn (1965) as Bell Lake Nickel - Prospect 8
which was discovered around 1891.
196
Figure 5-45. General geology and sample locations from the Bell Lake intrusion, Lorne
Township. Geology modified after Ginn (1965). Map coordinates are UTM, NAD27-
Zone17.
197
Sample JB98-151C was collected from the gabbro, very near the northern contact (not
exposed). Sample JB98-151A, collected from the same general area as JB98-151C was
described in the field as an altered fine-grained gabbro. In thin section, this sample
consists of an equigranular mosaic of ~45% fine-grained feldspar and quartz, and ~45%
chlorite, with chlorite also occurring as rare pseudomorphs after pyroxene, and ~5%
opaques (likely magnetite); several very fine grains of sulphide were noted.
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB98-151A altered gabbro 0.005 76 347 0.277 0.640 0.673 20.890 29.500JB98-151C GN (H-O) 0.005 19 264 0.841 1.940 1.410 11.690 7.090JB98-150 LG (Q-H) 0.005 44 293 1.146 2.540 1.540 13.260 6.120JB98-149 GN (H-O) 0.005 44 332 1.301 2.500 1.900 12.140 6.480JB98-148 LGN (H-O) 0.008 32 376 1.124 2.380 2.500 12.770 4.300JB98-147 MGN (H-O) 0.005 15 355 1.077 1.680 3.070 10.590 2.260JB98-146 GN (H-O) 0.018 114 188 0.101 0.580 0.530 4.820 6.450JB98-145 sediment 0.005 208 40 0.017 0.085 0.027 0.733 0.543Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB98-151A 16.700 19 658 1.4 0.1 69 7 5.10JB98-151C 1.430 39 2632 0.6 0.1 77 28 1.86JB98-150 0.645 30 1136 0.5 0.1 78 30 2.67JB98-149 0.763 16 1136 0.5 0.0 81 22 1.75JB98-148 1.060 33 2500 0.3 0.1 81 17 1.70JB98-147 0.730 6 3333 0.2 0.0 82 14 0.98JB98-146 1.540 55 1579 1.3 0.3 73 32 2.14JB98-145 1.380 26 240 0.7 0.7 53 102 3.00
Table 5-13. Summary of whole-rock geochemical characteristics for samples from the
Bell Lake intrusion, Lorne Township. "-" below lower limit of detection; "N" = primitive
mantle-normalized; G=gabbro; OLGN=olivine leucogabbronorite; LG=leucogabbro;
GN=gabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-
hypersthene-corundum. Norm wt% = rock types determined on the basis of weight
percent normative minerals calculated to normative weight percent.
198
On the basis of the hand sample description, its location in the section, the CIPW
normative calculation, and thin section information, this sample is interpreted to represent
an extensively altered fine-grained or chilled gabbro that likely contained pyroxene
(hypersthene?) phenocrysts.
Northeast and southwest from the sample section, there are several magmatic Cu-Ni
sulphide occurrences either entirely within the intrusion or at the contact between the
Nipissing Gabbro and hosting sedimentary rocks (Ginn, 1965). Several samples (JB97-
39A, 39B, 39C, 85A and JB98-117B, 117C) were collected from one of the Cu-Ni
showings in Nairn Township and these samples are included in the regional sample
database. Ginn (1965) also described Cu-Ni sulphide mineralization exposed in an old
pit, located northwest of Bell Lake and at the northwest end of the current sample section
(Fig. 5-45). Ginn (1965) described two pods of olivine diabase and mapped several areas
of olivine diabase within a Nipissing Gabbro sill that parallels the Bell Lake intrusion to
the southwest in Nairn Township.
The northwest region of Lorne Township including the area covered by the current
sample section, was the target of Tearlach Resources Inc. multi-year exploration
programs (2001 to 2003) aimed at delineating a newly recognized portion of the
Worthington Offset dike (Fig. 5-45). Ginn (1965) mapped the fragment-bearing quartz
diorite dike as part of the larger Nipissing Gabbro (Bell Lake intrusion) and surmised that
the Worthington Offset dike previously recognized by Card (1965) to the north in Drury
Township did not continue southward into Lorne Township. Exploration work by
Tearlach, traced the quartz diorite dike from the southwest, about 50 m northeast of the
old pit at the north end of the sample section, toward the northeast where it is cut off by
the Murray Fault (Butler, 2002). A further ~3 km to the east, the Worthington Offset dike
stricto sensu, terminated at its southern end by the Murray Fault, continues northeast
toward the Sudbury Igneous Complex. In the area of the Bell Lake section, the
Worthington Offset dike, which is associated with the magmatic events of Sudbury
Igneous Complex (~1.85 Ga), intruded McKim Formation sediments and is proximal
(~50 m) to the older Bell Lake Nipissing Gabbro intrusion.
199
Photo 5-3. Heavily gossaned Nipissing Gabbro from the northern part of the traverse
across the Bell Lake Intrusion, near sample site JB98-151. This sulphide showing is
described by Ginn (1965) as the Bell Lake Nickel prospect #8 (ca. 1891). The height of
the exposure is about 4 metres.
200
This is important in the context of the sample section, and in particular sample JB98-
151A, because emplacement of the offset dike may have altered the McKim Formation
sediments and/or the northern portion of the Bell Lake intrusion, overprinting earlier
features. Grab samples from the pit located at the northern end of the sample section
were reported by Butler (2002) to assay 0.74% Cu, 0.48% Ni, 0.04% Co, 0.15 g/t Pt and
0.04 g/t Pd (20% visible sulphide), and 0.04% Cu, 1.32% Ni, 0.135% Co, 0.19 g/t Pt and
0.19 g/t Pd (90% visible sulphide). Butler (2002) noted that although the Cu-Ni-Pt-Pd
concentrations are comparable to this portion of the Worthington Offset dike, Co
concentrations in Nipissing Gabbro are enriched by a factor of ~2-3.
5.7.2 Major Element Variations
CIPW normative calculations were completed on the six gabbroic samples collected
from the Bell Lake intrusion (Table 5-13). Of the six samples, three classify as
hypersthene-olivine-normative (silica-saturated) gabbronorite, one as quartz-hypersthene-
normative (silica-oversaturated) leucogabbro, one as hypersthene-olivine-normative
leucogabbronorite, and one as hypersthene-olivine-normative melagabbronorite. In the
field, the CIPW gabbronorite samples were described as gabbro and quartz gabbro, the
leucogabbro and leucogabbronorite samples were described as gabbro and the CIPW
melagabbronorite was described as orthopyroxene gabbro. CIPW normative calculations
on JB98-151A, show this sample to be olivine-hypersthene-corundum-normative (silica
saturated and peraluminous) with more than 30% normative olivine. The major element
chemistry of the Wright showing samples (JB98-117B and 117C), collected from the
southwest part of the intrusion in Nairn Township, are similar to those of the Bell Lake
intrusion (i.e. ~9.9-12.8 wt% MgO).
All of the gabbroic samples plot with higher Mg-number and lower TiO2
concentrations relative to average chilled margin gabbro (Fig. 5-46). Assuming that
average chilled margin is a good estimate of parent magma composition, it follows that
these rocks are either much more primitive (less fractionated) relative to “normal” or
average Nipissing Gabbro or that they contain a high percentage of orthopyroxene
phenocrysts and/or olivine (now altered). As with other relatively undifferentiated
intrusions that contain massive units of orthopyroxene gabbro, the rocks in the Bell Lake
section probably originally contained upwards of 10% hypersthene phenocrysts.
201
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
40455055606570758085
Mg-number
TiO
2 (w
t%)
JB98-151A (HW)JB98-151CJB98-150JB98-149JB98-148JB98-147JB98-146JB98-145 (FW)Chilled Margin Avg
fractionationg altered gabbro (chill)A melagabbronorite (CIPW)) gabbronorite (CIPW)# leucogabbro (CIPW)D leucogabbronorite (CIPW)
Figure 5-46. Bivariate scatter plot of samples from the Bell Lake intrusion using the
calculated Mg-number and wt% TiO2; for comparison, average chilled margin gabbro
from the present study is also shown.
202
Therefore, these rocks that have higher than “normal” MgO compositions are interpreted
to represent hypersthene cumulates and therefore have compositions that, unlike the
chilled margin gabbro, do not represent liquids.
Whole-rock major element compositions show very little variation throughout the
section, averaging about 51.4 wt% SiO2, 16 wt% MgO, 0.35 wt% TiO2 and an Mg-
number of ~79. A very subtle decrease in Mg-number and an increase in TiO2 suggests
that the lower portion of the intrusion is located to the south, along the north edge of Bell
Lake. Sample JB98-151A, an altered chilled gabbro from the northernmost part of the
section, is characterized by low SiO2 (~40 wt%), relatively low TiO2 (~0.1 wt%) and very
high Al2O3 (~24 wt%) which is contrasted by the footwall sediment whose composition
is ~76 wt% SiO2, 0.35 wt% TiO2, and 11.23 wt% Al2O3; loss on ignition for JB98-151A
is ~7 wt%.
5.7.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams for the Bell Lake section are
shown in Figure 5-47. The gabbroic samples show similar overall trace and rare-earth
element abundances (~1 to 40 times primitive mantle) with moderate LILE enrichment
(~1-50 times primitive mantle), average of ~1.9 (La/Sm)N, and weakly enriched HREE
(~1-3 times primitive mantle); these values are generally lower in comparison to other
Nipissing Gabbro intrusion (e.g. Lightfoot and Naldrett, 1996). As is typical of Nipissing
Gabbro, all of the gabbroic samples display strong negative Nb+Ta and P* anomalies,
and moderate Ti* anomalies, which are features characteristic of magma interacting with
a crustal component. Sample JB98-151A plots well below the range for typical Nipissing
Gabbro, and relative to average chilled gabbro displays pronounced negative Th, Nb, La
and Ce anomalies, a strong positive Sr anomaly, and a weakly positive Ti* anomaly. The
ratio of La/Ce is an important indicator of alteration in volcanic systems (e.g. Wyman,
1996) whereby higher La/Ce ratios suggest increased alteration. Sample JB98-151A has
a higher ratio of (La/Ce)N (~1.42) relative to average gabbroic samples (~1.2) which
suggests that this sample has experienced extensive alteration.
203
0.01
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-151C
JB98-150
JB98-149
JB98-148
JB98-147
JB98-146
Chilled Margin Avg
A melagabbronorite (CIPW)) gabbronorite (CIPW)# leucogabbro (CIPW)D leucogabbronorite (CIPW)
(A)
0.01
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-151A (HW)
JB98-145 (FW)
Chilled Margin Avg
(B)
g altered gabbro (chill)+ sediment
Figure 5-47. Primitive mantle-normalized multi-element diagrams for rock samples from the Bell Lake intrusion, Lorne Township. (A) Gabbroic samples. (B) Atypical profiles. Mantle normalizing values are from McDonough and Sun (1995).
204
5.7.4 Chalcophile (PGE, Cu, Ni) Element Variations
None of the samples analyzed have any visible sulphide and moreover, 4 of the 6
gabbroic samples analyzed are below the lower limit of detection for S (generally 0.01
wt% S); in cases where S values are below the lower limit of detection (LLD), a value
equal to 0.5 x LLD is used, and in this case it is 0.005 wt% S. The 6 gabbroic samples
are characterized by averages of ~301 ppm Ni, ~30 ppm Cu, 0.93 ppb Ir, 1.94 ppb Ru,
1.83 ppb Rh, 10.88 ppb Pt, 5.45 ppb Pd, and 1.03 ppb Au. The highest concentration of
Pt+Pd (~21 ppb Pt+Pd; 1.4 Pd/Pt; 0.05 Cu/Ni) is from the uppermost sample (JB98-
151A), which is thought to be an altered and recrystallized gabbro.
Selected chalcophile elements and ratios are plotted against relative distance through
the intrusion in Figure 5-48. Concentrations of Se are highest in the lowermost quartz
gabbro and uppermost altered gabbro, lowest in the uppermost gabbro unit, and shows a
progressive increase through the middle region of the intrusion. The ratio of S/Se
increases rapidly through the lowermost quartz gabbro and subsequent orthopyroxene
gabbro, then drops sharply through he middle of the intrusion, before rising again in the
upper gabbro unit and finally dropping off in the uppermost altered gabbro. With the
exception of the uppermost (JB98-151A) and lowermost (JB98-145) samples, all of the
rocks have S/Se ratios that fall within the range of uncontaminated magmatic sulphide
(Naldrett, 1981). Samples JB98-151A and JB98-145 have S/Se values that are <1000
which is indicative of S loss (Reeves and Keays, 1995). Given that almost all of the S
analyses were below the LLD it is possible that S loss affected other samples.
Concentrations of Pt and Pd display a general increase through the intrusion ranging
from ~11 ppb Pt+Pd at the base to a maximum of ~21 ppb Pt+Pd in the uppermost altered
gabbro. The ratio of Pd/Pt is highest in the lowermost quartz gabbro, dropping quickly in
the orthopyroxene gabbro, and then increasing steadily into the upper altered gabbro;
Pd/Ir ratios are highest in the lowermost quartz gabbro and uppermost altered gabbro.
The Cu/Pd ratio displays a general decrease upward through the intrusion, from 8527 in
the lower quartz gabbro to 644 in the upper altered gabbro. Plots of Pt/Se and Pd/Se (Se
was used in place of S as sulphur loss was suspected) exhibit a gradual increase from the
quartz gabbro to the overlying orthopyroxene unit, followed by a gradual increase
through to the uppermost gabbro.
205
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000 10000 100000 1000000
Concentration and Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
orthopyroxene gabbro (MGN)
gabbro (GN)
gabbro (LG)
sediment
quartz gabbro (GN)
SOUTH
NORTH
gabbro (GN)
gabbro (LGN)
altered gabbro (chill)
(A)
Pt+Pd (ppb) Cu (ppm) Ni (ppm) S (ppb)Cu/PdS/Se
Figure 5-48a. Profiles through the Bell Lake intrusion sample section, showing
stratigraphic variations in Pt+Pd, Cu, Ni, S/Se, Cu/Pd, and S. The relative vertical scale is
in metres.
206
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10
Concentration and Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
orthopyroxene gabbro (MGN)
gabbro (GN)
gabbro (LG)
sediment
quartz gabbro (GN)
SOUTH
NORTH
gabbro (GN)
gabbro (LGN)
altered gabbro (chill)
(B)
Pd/SePt/Se
Cu/Ni Pd/Pt
Figure 5-48b. Profiles through the Bell Lake intrusion sample section, showing
stratigraphic variations in Pd/Se, Pt/Se, Cu/Ni, and Pd/Pt. The relative vertical scale is in
metres.
207
The ratios are nearly identical in the lower quartz gabbro but quickly decouple through
the main body of the intrusion, reflecting high Pt/Pd ratios, followed by a reversal to
higher Pd/Pt in the upper altered gabbro. Concentrations of Ni are relatively steady
throughout the intrusion showing a subtle decrease upward from the orthopyroxene
gabbro to the upper gabbro unit, followed by a slight rise in the uppermost altered
gabbro.
Primitive mantle-normalized PGE and chalcophile element diagrams, with metals
recalculated to 100% sulphide, are shown in Figure 5-49. Three distinct groups are
apparent from this plot; Group-1, comprising the lowermost quartz gabbro (JB98-146),
shows a fractionated, positive slope profile (Fig. 5-49a); Group-2, comprising 5 gabbroic
samples, have elevated Ni, Ir, Ru, Rh and Pt and display only slight positive slopes in Ni-
Ir-Ru-Rh, followed by near-flat to slightly negative slopes in Pt-Pd-Au-Cu (Fig. 5-49a);
Group-3, consists of a sample of altered chilled margin gabbro (JB98-151A) and exhibits
a fractionated, positive slope from Ir through to Au, and a strong negative slope from Au
to Cu. The Group-1 data show typical Nipissing Gabbro fractionation patterns with early
crystallization of olivine and/or oxide and/or monosulphide solid solution (mss) having
depleted the magma in Ni-Ir-Ru-Rh, leaving relatively elevated Pt-Pd-Au-Cu. This
pattern approximates that of average chilled margin and average continental flood basalt.
The Group-3 patterns are very unusual for Nipissing Gabbro and resemble those of near-
mantle or primary partial melts such as the lower group chromitites of the Bushveld
Complex (e.g. Maier et al., 1998). The elevated Ni-Ir-Ru-Rh values reflect the primitive
chemistry of these rocks which have very high MgO compositions (range ~14.4-19.4
wt% MgO) relative to other Nipissing Gabbro (cf. Lightfoot and Naldrett, 1996). This
elevated pattern may also reflect the mineral chemistry of these samples, with the
majority (4 of 5) having >3% normative olivine. As discussed earlier (see Section 5.2.3),
the ratio of Pd/Ir is important in estimating the degree of fractionation in a magma. The
fact that the Group-2 samples have PGE patterns that plot with much lower relative Pd/Ir
values to that of continental flood basalt and typical Nipissing Gabbro, indicates that
these rocks formed from magmas that were not as fractionated as those from average
continental flood basalt.
208
1
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1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-151C
JB98-150
JB98-149
JB98-148
JB98-147
JB98-146
Chilled Margin Avg
Flood Basalt Avg
Group-1
Group-2
A melagabbronorite (CIPW)) gabbronorite (CIPW)# leucogabbro (CIPW)D leucogabbronorite (CIPW)
(A)
Figure 5-49a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for Group-1 and Group-2 sulphides from the
Bell Lake intrusion sample section, Lorne Township. Data for average chilled margin is
from this study; data for average flood basalt is from Naldrett (1981). Mantle
normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
209
1
10
100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-151A (HW)
JB98-145 (FW)
Chilled Margin Avg
Flood Basalt Avg
g altered gabbro (chill)
(B)
Group-3
Group-1
Figure 5-49. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for Group-3 sulphides from the Bell Lake
intrusion sample section, Lorne Township. Sample JB98-145 shares similarities to
Group-1 sulphides. Data for average chilled margin is from this study; data for average
flood basalt is from Naldrett (1981). Mantle normalizing values are from Barnes et al.
(1988) and McDonough and Sun (1995).
210
The Group-3 profile is similar to that of Group-1 but with elevated overall PGE
abundance, suggesting further fractionation relative to Group-1; elevated Ni-Ir-Ru-Rh
also reflects the primitive nature of this sample (~11 wt% MgO).
For comparison, 5 of the samples (JB97-39A, 39B, 39C, 85A) collected from the
Wright showing in Nairn Township are considered. These samples, considered to be
from the same intrusion as the Bell Lake section, are characterized by relatively high S
(1.3-15.7 wt%), Ni (1202-13000 ppm) and Cu (650-27583 ppm) concentrations and
anomalous Pt (30.3-218.1 ppb) and Pd (21.4-122.6 ppb) concentrations. In terms of S/Se
ratios, samples with semi-massive to massive sulphide (7.63-15.70 wt% S) show
contamination signatures (11,787-2,461,290 S/Se) whereas samples (JB97-85A and
JB98-117B) with disseminated textured sulphide (1.3-9.4 wt% S) show magmatic
signatures (2369-4134 S/Se). The chondrite-normalized Pd/Ir ratios for samples from the
Nairn site (Fig. 5-2.15a) are similar to those from the Bell Lake sample section (Fig. 5-
49).
5.8 Makada Lake Intrusion – Traverse
The Makada Lake Intrusion, located about 15 km southwest of the City of Greater
Sudbury in the central part of Waters Township, extends for about 5 km in a southwest
direction (~55 Az) along the northwest shore of Makada Lake (Figs. 1-2 and 5-50). The
sample section, which is about 500 m wide, extends north from the northwest shore of
Makada Lake to the northern contact of the intrusion, exposing gabbroic rocks and the
footwall and hangingwall Huronian sedimentary rocks. A total of 22 samples were
collected to construct a lithostratigraphic section through the intrusion, along with an
additional five grab samples collected from various sulphide showings (Fig. 5-51). A
summary of the samples is provided in Table 5-14 and a complete listing of the data is
provided in Appendix 1.
5.8.1 Geology and Mineralization
The Makada Lake intrusion is located about 3.7 km south of the Murray Fault Zone
(Fig. 5-50) and Card (1968) interpreted this and other Nipissing Gabbro bodies in the
region to be sill-like and generally paralleling regional structural trends. Several 050 Az
tight folds occur in the region with anticline and synclines axes traces generally separated
by ~500-1000 m and on the basis of mapping by Card (1968), the Makada Lake sill
211
appears to have intruded folded Huronian sediments and is now, for the most part,
conformable to bedding (Fig. 5-50; Photo 4-2). Faults on the property are generally
oriented at 290-300 Az and 330-350 Az (Fig. 5-51) and are interpreted to have a
dominantly dip-slip component.
Figure 5-50. General geology and location of the sample section for the Makada Lake
intrusion, Waters Township. Geology after Card (1968).
212
Figure 5-51. General geology and locations of samples collected from the Rauhala
property, Makada Lake intrusion, Waters Township.
213
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB97-78A OGN (H-O-C) 0.170 309 94 - - 0.820 5.000 10.410JB97-78B aplite 0.600 1122 68 - - - - 7.480JB97-76A G (Q-H) 0.150 228 170 - - 1.100 9.560 13.450JB97-76B GN (H-O) 0.800 1134 210 - - 0.570 5.460 5.370JB97-77A LGN (H-O) 0.190 321 85 na na na na naJB97-77B GN (H-O) 0.850 1563 190 - - 0.670 9.280 15.170
RK-14 GN (H-O) 0.019 78 138 0.050 0.420 0.520 6.300 8.930RK-19 LGN (H-O) 0.014 85 117 - 0.330 0.410 4.640 5.860RK-13 G (Q-H) 0.021 84 137 0.060 0.350 0.510 6.220 7.800RK-18 LGN (H-O) 0.011 58 342 1.340 2.710 1.800 11.370 5.820
JB97-75 LG (Q-H) 0.030 281 53 - - - - -RK-5 LG (Q-H) 0.038 219 67 - - - 0.200 -RK-2 OGN (H-O) 0.011 35 214 0.220 1.050 1.480 6.240 4.180
JB97-4B G (Q-H) 0.020 101 220 0.302 1.118 0.801 5.851 11.549RK-12 G (Q-H) 0.014 64 327 1.040 2.460 1.540 9.190 5.300RK-7 GN (H-O) 0.013 74 248 0.550 1.410 1.230 7.350 6.360
RK-11 G (Q-H) 0.023 73 346 1.090 2.580 1.840 9.960 5.530JB97-79B G (Q-H) 0.010 73 212 - - - 5.050 10.320
RK-8 GN (H-O) 0.018 87 259 0.570 1.450 1.120 7.630 6.590RK-9 GN (H-O) 0.014 65 338 1.050 2.590 1.590 9.270 5.380
RK-10 GN (H-O) 0.012 61 335 1.100 2.630 1.850 11.060 5.640JB98-114 GN (H-O) 0.014 57 311 0.392 1.250 0.873 5.470 6.070JB98-165 leucogabbro 14.500 80 3062 0.744 1.830 5.020 18.770 30.500JB97-74A gabbro 1.050 1455 210 - - - - 10.430
RK-1 G (Q-H) 0.712 810 500 0.290 0.910 0.880 7.240 9.600RK-3 gabbro 1.410 1292 679 0.460 1.330 1.300 10.700 12.590RK-4 gabbro 36.300 41 10490 - - - - 1.490
Table 5-14. Summary of whole-rock geochemical characteristics for samples from the
Makada Lake intrusion, Waters Township. "-" below lower limit of detection; "N" =
primitive mantle-normalized; "na"=not analyzed; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; OGN=olivine gabbronorite;
LGN=leucogabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-
C=quartz-hypersthene-corundum; H-O-C=hypersthene-olivine-corundum.
214
Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB97-78A 2.040 82 5502 2.1 0.9 58 64 3.17JB97-78B 3.540 390 5348 - 5.7 46 30 1.58JB97-76A 5.870 45 6579 1.4 0.3 71 41 1.77JB97-76B 3.220 220 7055 1.0 1.0 66 48 0.87JB97-77A na 150 5919 - 1.8 55 60 2.02JB97-77B 288.750 880 5438 1.6 4.6 53 65 1.45
RK-14 1.670 66 2436 1.4 0.5 69 33 2.26RK-19 1.030 60 1647 1.3 0.5 67 33 2.32RK-13 1.230 61 2500 1.3 0.4 68 33 2.19RK-18 1.200 50 1897 0.5 0.1 79 23 1.78
JB97-75 - 112 1068 - 2.1 34 156 2.49RK-5 3.480 136 1735 - 2.0 44 115 2.31RK-2 2.090 14 3143 0.7 0.1 75 23 2.48
JB97-4B 3.689 93 1980 2.0 0.4 72 30 1.90RK-12 1.370 45 2188 0.6 0.1 78 24 1.83RK-7 1.820 71 1757 0.9 0.3 76 27 1.90
RK-11 1.370 50 3151 0.6 0.1 79 22 1.84JB97-79B - 53 1370 2.0 0.3 74 25 1.76
RK-8 1.490 73 2069 0.9 0.3 76 29 2.09RK-9 1.300 46 2154 0.6 0.1 79 24 1.76
RK-10 1.210 46 1967 0.5 0.1 79 24 1.79JB98-114 2.430 37 2456 1.1 0.1 78 19 1.48JB98-165 238.000 1702 1812500 1.6 0.6 29 44 3.90JB97-74A 5.770 278 7216 - 1.3 54 25 3.94
RK-1 8.170 181 8790 1.3 0.4 76 34 2.42RK-3 16.700 349 10913 1.2 0.5 75 26 1.95RK-4 1.720 645 8853659 - 0.1 1 1 3.88
Table 5-14(cont). Summary of whole-rock geochemical characteristics for samples from
the Makada Lake intrusion, Waters Township. "-" below lower limit of detection; "N" =
primitive mantle-normalized; "na"=not analyzed; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; OGN=olivine gabbronorite;
LGN=leucogabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-
C=quartz-hypersthene-corundum; H-O-C=hypersthene-olivine-corundum.
215
The Makada Lake intrusion is hosted by sulphide-bearing (maximum of ~1% pyrite and
rare chalcopyrite) feldspathic quartzite, arenite and arkose of the Mississagi Formation
(upper Hough Lake Group), cut by magnetite-olivine gabbro of the Sudbury Dike Swarm
(oriented at ~300/90 Az), and cut by mafic, fragment-bearing dikes (oriented at ~80/90
Az) that may be related to the Sudbury Igneous Complex.
The northern contact of the Makada Lake intrusion is not exposed but the southern
contact of the intrusion (Photo 4-2), where exposed, is sharp against the sediments,
marked by fine-grained to chilled gabbroic rocks over widths of about 1 metre; the
sedimentary rocks are locally sheared along the contact region. From south to north, the
sample suite consists of medium-grained orthopyroxene gabbro which is gradational into
a dominantly gabbro unit with subordinate orthopyroxene gabbro, followed by vari-
textured gabbro and gabbro. Granophyric gabbro with aplite dikes and felsic
differentiates occur mainly in the southern area of the section (Fig. 5-51).
The Makada Lake Intrusion is interpreted to represent an upper limb or near-arch
portion of an undulatory sill (Fig. 5-52), and as with other exposures of Nipissing
Gabbro, topography plays a role in terms of exposing various levels of stratigraphy. In
this case, elevation ranges from about 240 m ASL in the north (area of JB97-114),
cresting at about 290 m ASL in the southern half of the section (area of JB97-75), and
then dropping off along the northwest shore of Makada Lake to about 250 m ASL in the
area of the sediment-gabbro contact (JB97-78A,B). A consequence of this gradual rise
and variation in topography from north to south is the exposure of deeper parts of the sill
in the north and higher parts of the sill in the middle and southern areas. For example,
gabbro pegmatite (Photo 4-11), granophyric rocks, aplitic pods, and sedimentary
fragments in gabbro (Photo 5-4a) occur in the middle region of the traverse (Fig. 5-51;
area of Pit #2, #3 and #4), enveloped by massive mafic gabbros north and south from this
region. The stratigraphic location of these mineralized exploration pits and field
evidence for extensive hydrothermal alteration and/or magmatic fluid accumulation (i.e.
pegmatitic textures) in this area, suggests that these pits were proximal to the now eroded
sedimentary roof rocks of the intrusion.
The Makada Lake intrusion is host to several Ni-Cu-PGE sulphide occurrences as
well as several showings of polymetallic Au-Ag-Co-Cu-Ni veins.
216
Figure 5-52. Schematic diagram showing the interpreted structure of the Makada Lake
intrusion, Waters Township. NG=Nipissing Gabbro; opxG=orthopyroxene gabbro;
G=gabbro; vtG=vari-textured gabbro; GG=granophyric gabbro; AP=aplite; FD=felsic
differentiate. The cross section is based on the undulatory model for Nipissing Gabbro
intrusions (Hriskevich, 1968).
217
All of these sulphide occurrences are found within the present study area which is
colloquially referred to as the Rauhala property. The majority of Cu-Ni sulphide
mineralization occurs within the middle region of the sample section where it is exposed
in 3 exploration pits – Pit #2, #3 and #4 (Fig. 5-51). At these locations, sulphides occur
as semi-massive to massive accumulations which appear to be localized into lenses or
pods of limited strike extent; blue quartz “eye”–bearing gabbro is relatively common in
this central area and is commonly directly associated with higher percentages of sulphide
mineralization. Massive and semi-massive sulphide mineralization is dominated by
pyrrhotite, but disseminated chalcopyrite and/or pyrrhotite is relatively common
throughout the Nipissing Gabbro units. Disseminated sulphides (Photo 5-4b), dominated
by pyrrhotite with subordinate chalcopyrite, occur in the gabbroic host rocks, resulting in
a several metre wide mineralized halo, northwest and southeast of the pit area. Up-
section or southward from the pits, toward Makada Lake, sulphide mineralization is
patchy.
Pit #1 consists of highly altered fine-grained gabbro with sediment fragments and
quartz (+/- carbonate) veining, and is located near the contact with quartz arenite; the
sediment is likely a roof pendant or block derived from the now eroded hangingwall
sedimentary rocks; polymetallic veins containing anomalous Ag-Ni-Co-As-Au occur in
this area. Exploration pits Pit #2, Pit #3 and Pit #4, lie along a 060-240 Az trend, located
about 70 m northwest of the highest ridge along the section (Fig. 5-51). Pit #2 contains a
several “boulder” like outcrops of gossanous massive sulphide that are exposed in an ~5
x 5 m sandy and sulphur-rich pit; sulphides are mainly pyrrhotite with subordinate
chalcopyrite. The highest concentrations of Pt+Pd are from samples JB98-165 (~49 ppb
Pt+Pd; 1.6 Pd/Pt; 0.6 Cu/Ni; 0.31% Ni, 0.17% Cu) and RK-3 (~23 ppb Pt+Pd; 1.2 Pd/Pt;
0.5 Cu/Ni), collected from the massive sulphide in Pit #2. Samples RK-1, 3 and 4 were
also collected from Pit #2, with RK-4 assaying 1.05% Ni and 0.07% Cu. Pit #3 contains
numerous rock types arranged in a complicated and highly altered assemblage, including
pegmatitic “golf ball” gabbro, vari-textured gabbro, aplite, sediment, granophyric gabbro
and quartz-bearing gabbro.
218
Photo 5-4. Makada Lake Intrusion. (A) Fragments of Huronian Supergroup sedimentary rocks in fine- to medium-grained gabbro of the Makada Lake Intrusion. The fragments are thought to have been stoped from what was overlying sedimentary roof rocks. The hammer handle is about 90 cm long. (B) Extensively altered gabbro with fine-grained blue quartz and finely disseminated sulphide (ds), dominated by pyrrhotite with subordinate chalcopyrite; sample is from exploration Pit#2 (Figure 5-51). The pen magnet is about 9 cm long.
219
Fine-grained, acicular amphibole and other hydrous phases are common, and together
with other fractionated rock types, and a high degree of alteration, suggests a highly
fluidized system – likely a combination of late magmatic fluids and post-magmatic
hydrothermal fluids. Mineralization consists mainly of finely disseminated pyrrhotite,
pyrite and chalcopyrite as well as fracture and vein-controlled sulphide and localized (cm
wide and cm long) veins of semi-massive pyrrhotite + pyrite > chalcopyrite. Sample
JB97-4B, collected from the northern edge of the pit, assayed 220 ppm Ni, 93 ppm Cu,
5.9 ppb Pt, 11.6 ppb Pd, and 3.7 ppb Au. Pit #4 consists of sedimentary rock fragments
within medium-grained gabbro. It is not clear whether these are fragments of sediment
that have been incorporated into the gabbro during emplacement of if they represent
remnants of the now eroded overlying Huronian sediments. Mineralization is mainly
finely disseminated to locally bleb pyrrhotite, pyrite and chalcopyrite. The gabbroic
rocks have been recrystallized and thoroughly altered along with the sedimentary rocks.
Sample JB97-74A, collected from the edge of this pit, assayed 210 ppm Ni and 278 ppm
Cu and has anomalous PGE. The third highest Pt+Pd concentration is from JB97-77B
(~25 ppb Pt+Pd; 1.6 Pd/Pt, 4.6 Cu/Ni), collected from the southern area of the section.
A diamond drill hole (A1-97), targeting the mineralization under the western edge of
Pit #2 (Fig. 5-51), intersected gabbro over its entire length (~55 m) with one section from
~34 m to 54 m that consisted of ~10% disseminated chalcopyrite and pyrrhotite in an
altered, biotite- and blue quartz-bearing, medium-grained, gabbro; details of this drill
hole are discussed in Section 5.9.
5.8.2 Major Element Variations
CIPW normative calculations were completed on the 22 of the section samples and
one of the mineralized grab samples (Table 5-14; Appendix 1). Eight of the samples,
classifying as hypersthene-olivine-normative (silica-saturated) gabbronorites, are the
dominant rock type in the northern part of the section and correlate well with
orthopyroxene gabbro. One sample of orthopyroxene gabbro classified as a hypersthene-
olivine-normative, olivine gabbronorite. Six of the samples, classifying as quartz-
hypersthene-normative (silica-oversaturated), correlate with gabbro from the northern
part of the section and two samples of vari-textured gabbro from the south. CIPW
normative calculations for five samples of leucogabbro and vari-textured gabbro,
220
collected from the southern half of the section, result in hypersthene-olivine-normative
leucogabbronorites and quartz-hypersthene-normative leucogabbros.
A plot of Mg-number versus TiO2, useful to determine fractionation patterns, is
provided in Figure 5-53. From north to south, the samples show a reasonably regular
fractionation trend with higher MgO and lower TiO2 rocks from the north and lower
MgO and slightly higher TiO2 in rocks from the south. This trend, along with the
prevalence of orthopyroxene gabbro in the north part of the section, suggests that the
basal or lower portion of the sill is toward the north and that the upper portion of the sill
is toward the south. All but 6 of the samples plot with significantly higher Mg-numbers
and slightly lower TiO2 values relative to average chilled margin. This reflects the high
proportion of orthopyroxene phenocrysts in these rocks and the fact that these rocks are
cumulates, not liquids. Concentrations of MgO in the lowermost 10 samples (northern
part of section) range 10.7 to 17.35 wt% MgO which is very high for Nipissing Gabbro.
For comparison, Lightfoot and Naldrett (1996) reported 8.1 wt% MgO for average
gabbro (21 different intrusions) and 8.8 wt% MgO for average chilled margin (seven
different intrusion).
Variations in selected major elements across the intrusion, using relative distance
from north to south, are provided in Figure 5-54. The concentration of SiO2 shows a very
general increase, except within the upper aplite/differentiate, where it spikes to over 70
wt%, and in the upper granophyric gabbro where it drops to ~48 wt%. Concentrations of
TiO2 exhibit a general increase upward (from north to south) through the intrusion with
several spikes in the upper vari-textured gabbro dominated units. Sample JB97-75
records the highest TiO2 concentration, is located at the highest elevation on the section
and is described as a coarse-grained to pegmatitic gabbro pod. Assuming that the highest
elevation on the section would have been closest to the now eroded hangingwall
sediments, then elevated TiO2 could reflect local contamination from roof rocks and/or an
accumulation of late differentiated (TiO2 enriched) magma toward the roof. Decreasing
Mg-number, characteristic of normal magma differentiation, is evident from north to
south through the intrusion with most of the highest Mg-numbers correlating with the
lowermost orthopyroxene gabbro (CIPW gabbronorite); the lowest Mg-number is from
sample JB97-75.
221
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
30405060708090
Mg-number
TiO
2 (w
t%)
JB97-78AJB97-78BJB97-76AJB97-76BJB97-77AJB97-77BRK-14RK-19RK-13RK-18JB97-75RK-5RK-2JB97-4BRK-12RK-7RK-11JB97-79BRK-8RK-9RK-10JB98-114Chilled Margin AvgHuronian Sediment Avg
fractionation
g differentiate(?)/aplite(?)A gabbro (CIPW)) gabbronorite (CIPW)B olivine gabbronorite (CIPW)# leucogabbro (CIPW)D leucogabbronorite (CIPW)
gabbro pegmatite pod
Figure 5-53. Bivariate scatter plot of samples from the Makada Lake intrusion using the
calculated Mg-number and wt% TiO2; for comparison, average chilled margin gabbro
from the present study is also shown.
222
0
50
100
150
200
250
300
350
400
450
500
30 40 50 60 70 80 90
SiO2 (wt%) and Mg-number
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
granophyric gabbro (OGN)
sediment NORTH
SOUTH
vt gabbro (G)
gabbro (GN)
aplite/differentiate
vt gabbro (GN)
vt gabbro (LGN)
opx gabbro (GN)
gabbro (G)
vt gabbro (LG)
gabbro (GN)
opx gabbro (OGN)
gabbro (LG)
(A)
Mg-numberSiO2
Figure 5-54a. Profiles through the Makada Lake intrusion showing stratigraphic
variations in Mg-number and SiO2. The relative vertical scale is in metres.
223
0
50
100
150
200
250
300
350
400
450
500
0.1 1.0 10.0
TiO2 (wt%)
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
granophyric gabbro (OGN)
sediment NORTH
SOUTH
vt gabbro (G)
gabbro (GN)
aplite/differentiate
vt gabbro (GN)
vt gabbro (LGN)
opx gabbro (GN)
gabbro (G)
vt gabbro (LG)
gabbro (GN)
opx gabbro (OGN)
gabbro (LG)
(B)
Figure 5-54b. Profiles through the Makada Lake intrusion showing stratigraphic
variations in TiO2. The relative vertical scale is in metres.
224
5.8.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams are shown in Figure 5-55.
With the exception of the two CIPW leucogabbro samples (JB97-75 and RK-5), the
gabbroic samples show near-parallel patterns with strong LILE enrichment, follow
closely the pattern of average chilled margin, and have moderate to pronounced negative
Nb+Ta and P* anomalies and moderate to weak Ti* anomalies; features which are typical
of Nipissing Gabbro magmas. Most of the samples with the highest concentrations of S
and visible sulphide, also display the most erratic and varying trace and REE patterns,
suggesting extensive re-mobilization as a result of secondary (post magmatic) processes
such as hydrothermal alteration.
5.8.4 Chalcophile (PGE, Cu, Ni) Element Variations
As described earlier, the majority of PGE-Cu-Ni sulphide mineralization occurs
within the middle region of the sample section where it is exposed in three exploration
pits – Pit #2, #3 and #4 (Fig. 5-51). Smaller sulphide showings, commonly hosted by
gabbro-sediment “breccias”, are scattered throughout the southern area of the sample
section. Selected chalcophile elements and their ratios are plotted against the relative
distance through the intrusion, from north to south (Fig. 5-56). There are two
pronounced deflections in the general trends; one is located at ~265 m (between samples
RK-2 and RK-5), corresponding to a change from CIPW gabbronorite (orthopyroxene
gabbro and gabbro) dominated rocks to vari-textured gabbroic rocks; and, a second break
at ~400 m (between samples RK-14 and JB87-77B), which corresponds to samples that
have higher S concentrations and evidence for alteration and contamination from trace
and rare-earth elements. These breaks are best discerned in plots of S, Se, Pt+Pd, Pd/Pt
and Pt/Se-Pd/Se. The prominent drop in Pt+Pd at ~265 m corresponds with a spike in S
concentration, a signature of S-saturation that has been reported from numerous
intrusions (e.g. Reeves and Keays, 1985), and the distinct shift in Cu/Pd values at this
same stratigraphic height (~265 m) suggests that the magma had precipitated sulphide at
this stratigraphic level. In the field, the break at ~265 m (between RK-2 and RK-5)
occurs a few metres south (up-section) of the sulphide mineralized exploration pits.
225
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
RK-14RK-19RK-13RK-18JB97-75RK-5RK-2JB97-4BRK-12RK-7RK-11JB97-79BRK-8RK-9RK-10JB98-114Chilled Margin Avg
A gabbro (CIPW)) gabbronorite (CIPW)B olivine gabbronorite (CIPW)# leucogabbro (CIPW)D leucogabbronorite (CIPW)
(B)
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-78A
JB97-78B
JB97-76A
JB97-76B
JB97-77A
JB97-77B
Chilled Margin Avg
(>0.1 wt% S)
g differentiate(?)/aplite(?)A gabbro (CIPW)) gabbronorite (CIPW)B olivine gabbronorite (CIPW)D leucogabbronorite (CIPW)
(C)
Figure 5-55. Primitive mantle-normalized multi-element diagrams for rock samples from the Makada Lake intrusion, Waters Township. (A) Gabbroic samples. (B) Atypical profiles. Mantle normalizing values are from McDonough and Sun (1995).
226
0
50
100
150
200
250
300
350
400
450
500
1 10 100 1000 10000 100000 1000000 10000000
Concentration and Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
granophyric gabbro (OGN)
sediment NORTH
SOUTH
vt gabbro (G)
gabbro (GN)
aplite/differentiate
vt gabbro (GN)
vt gabbro (LGN)
opx gabbro (GN)
gabbro (G)
vt gabbro (LG)
gabbro (GN)
opx gabbro (OGN)
gabbro (LG)
(A)
S (ppb)Pt+Pd (ppb) Cu/PdS/SeNi (ppm)
Cu (ppm)
Figure 5-56a. Profiles through the Makada Lake intrusion sample section, showing
stratigraphic variations in Pt+Pd, Cu, Ni, S/Se, Cu/Pd and S. The relative vertical scale is
in metres.
227
0
50
100
150
200
250
300
350
400
450
500
0.0001 0.001 0.01 0.1 1 10
Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
Pd/Se
Pt/Se
sediment
granophyric gabbro (OGN)
sediment NORTH
SOUTH
vt gabbro (G)
gabbro (GN)
aplite/differentiate
vt gabbro (GN)
vt gabbro (LGN)
opx gabbro (GN)
gabbro (G)
vt gabbro (LG)
gabbro (GN)
opx gabbro (OGN)
gabbro (LG)
(B)
Cu/Ni Pd/Pt
Figure 5-56b. Profiles through the Makada Lake intrusion sample section, showing
stratigraphic variations in Pd/Se, Pt/Se, Cu/Ni, and Pd/Pt. The relative vertical scale is in
metres.
228
At about 400 m, the values of S/Se increase to >5000 whereas, in contrast, the
samples from the lower two-thirds of the section have S/Se values that are within the
range (1000 to 5000) of uncontaminated magmatic sulphides (Naldrett, 1981).
Coincident with this sudden increase in S/Se at ~400 m is an increase in Cu/Pd and S
(Fig. 5-56). These corresponding increases indicate that sulphide segregation occurred at
~400 m. This sudden increase could be explained by the introduction of external S into
the magma, which would have increased the S/Se values. Alternatively, the segregation
of sulphides may have preferentially removed Se relative to Cu (Se and Cu have similar
partition coefficients), leading to elevated S/Se ratios. In the plots of Pd/Ir and Cu/Ni, the
uppermost samples have elevated values relative to the lower samples, suggesting that
hydrothermal processes were involved in the development of the upper sample sulphides
(Keays et al., 1982).
Primitive mantle-normalized PGE and chalcophile element diagrams (recalculated to
metals in 100% sulphide) are shown in Figure 5-57. Two distinct groups are apparent
from these plots; Group-1, comprising samples RK-2, 13, 14, 19, JB97-4B and JB98-114,
displays positive slopes that are similar to those of average continental flood basalt and
average chilled margin gabbro; and, Group-2, comprising samples RK-7, 8, 9, 10, 11, 12
and 18, has positive slopes but with pronounced elevation in concentrations of Ni-Ir-Ru-
Rh-Pt relative to average flood basalt and average chilled margin gabbro. Group-1
samples (Fig. 5-57b), collected from sites across the width of the intrusion, show typical
Nipissing gabbro fractionation patterns and correlate mainly with CIPW gabbro and
gabbronorite. Group-2 samples (Fig. 5-57c), collected from sites located mainly in the
northern (lower) parts of the section, have MgO compositions (i.e. ~12-17 wt% MgO)
that are unusually high relative to other Nipissing Gabbro (cf. Lightfoot and Naldrett,
1996), and as seen elsewhere in this study, probably reflect a high proportion of
orthopyroxene phenocrysts and/or olivine. Moreover, as seen in samples from the Bell
Lake section and Nairn location, these PGE patterns, with much lower Pd/Ir values to that
of continental flood basalt, indicate that these rocks formed from magmas that were not
as fractionated as those which formed average continental flood basalt.
229
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
RK-14
RK-19
RK-13
RK-2
JB97-4B
JB98-114
Chilled Margin Avg
Flood Basalt Avg
EBL Hydrothermal Avg
GROUP-1
A gabbro (CIPW)) gabbronorite (CIPW)B olivine gabbronorite (CIPW)# leucogabbro (CIPW)
(A)
Figure 5-57a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for Group-1 sulphides from Makada Lake
intrusion rocks, Waters Township. Data for average chilled margin is from this study;
data for average flood basalt is from Naldrett (1981); data from average East Bull Lake
intrusion hydrothermal sulphide is from Peck et al. (1993b). Mantle normalizing values
are from Barnes et al. (1988) and McDonough and Sun (1995).
230
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
RK-18RK-12RK-7RK-11RK-8RK-9RK-10Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
GROUP-2
(B)
A gabbro (CIPW)) gabbronorite (CIPW)D leucogabbronorite (CIPW)
Figure 5-57b. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for Group-2 sulphides from Makada Lake
intrusion rocks, Waters Township. Data for average chilled margin is from this study;
data for average flood basalt is from Naldrett (1981); data from average East Bull Lake
intrusion hydrothermal sulphide is from Peck et al. (1993b). Mantle normalizing values
are from Barnes et al. (1988) and McDonough and Sun (1995).
231
0.01
0.1
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB97-78AJB97-76AJB97-76BJB98-165JB97-74ARK-1RK-3RK-4Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
(>0.1 wt% S)A gabbro (CIPW)) gabbronorite (CIPW)B olivine gabbronorite (CIPW)# leucogabbro (CIPW)
(C)
Figure 5-57c. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for high sulphur (>0.05wt% S) samples from
Makada Lake intrusion rocks, Waters Township. Data for average chilled margin is from
this study; data for average flood basalt is from Naldrett (1981); data from average East
Bull Lake intrusion hydrothermal sulphide is from Peck et al. (1993b). Mantle
normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
232
In Figure 5-57c, samples with high S concentrations (>0.1 wt% S) exhibit positive
fractionation patterns and are consistently depleted in PGE relative to average chilled
margin gabbro and average flood basalt; these patterns are interpreted to have resulted
from hydrothermal redistribution of the PGE.
5.9 Makada Lake Intrusion - Drill Hole A1-97
Diamond drill hole A1-97 (360 Az, -45 inclination), located about 30 m south of Pit
#2, targeted the mineralization under the western edge of Pit #2 (Fig. 5-51). The drill
hole intersected gabbro over its entire length (56.4 m) inclusive of an alteration zone
which extended from 37.19 m to 55.10 m. A total of 46 core samples were selected for
PGE, Au, S, Se and multi-element (Co, Cr, Cu, Ni) analyses; a complete listing of these
data is provided in Appendix 3. A summary of the drill hole information and data is
provided in Table 5-15. For the purposes of plotting, a value of one half of the lower
limit of detection is used where elements have concentrations that are below the lower
limits of detection; this is particularly relevant for Au, Pt and Pd, as the majority of
samples have concentrations that are below the lower limit of detection.
On the basis of geochemistry and geology from the surface section, this drill hole is
interpreted to have been drilled down-section toward the base (north) of the intrusion.
The drill hole intersected medium-grained gabbro over the first 36.47 m, followed by
altered gabbro to 55.10 m, and finally fine- to medium-grained gabbro to the end of the
hole; transition between the relatively fresh gabbro and the altered gabbro is gradational
over a few centimetres. The altered gabbro is characterized by green-grey colouration,
diffuse grain boundaries and patches of felt-textured mafic minerals. Within the
alteration zone (from 37.19 to 55.10 m), patches of blue quartz are a prominent feature
from 43.59-49.27 m. From about 49 to 51 metres the percentage of blue quartz decreases
and biotite becomes increasingly common, peaking in the altered biotite-rich gabbro from
51.21-55.10 m.
5.9.1 Chalcophile (PGE, Cu, Ni) and Trace Element Variations
Chalcophile elements (Pt, Pd, Au, Cu, Ni, S, Se) and minor elements (Cr, Co) are
plotted against depth in the drill hole in Figures 5-58 and 5-59. Highest concentrations of
Pt, Pd, Cu and Ni occur over a 0.65 m interval, from 53.95-54.76 m, in the altered biotite-
bearing gabbro.
233
0
10
20
30
40
50
601 10 100 1000 10000 100000 1000000 10000000
concentration (ppb)
Dril
l Hol
e Le
ngth
(m)
Au
SePt
Pd
Ni
Cu S
gabbro
gabbro(altered)
gabbro(altered-blue quartz)
gabbro(altered-biotite)
fg-mg gabbro
surface(A)
Figure 5-58a. Profiles through drill hole A1-97 from the Rauhala property (Makada Lake
intrusion), showing stratigraphic variations in Au, Pd, Pt, Se, Ni, Cu and S. Lower limits
of detection are: 2.5 ppb Au, 5 ppb Pd, 7.5 ppb Pt and 50 ppb Se.
234
0
10
20
30
40
50
6010 100 1000 10000
S/Se
Dril
l Hol
e Le
ngth
(m)
gabbro
gabbro(altered)
gabbro(altered-blue quartz)
gabbro(altered-biotite)
fg-mg gabbro
surface(B)
Figure 5-58b. Profiles through drill hole A1-97 from the Rauhala property (Makada Lake
intrusion), showing stratigraphic variations in S/Se.
235
0
10
20
30
40
50
601 10 100 1000 10000
concentration (ppm)
Dril
l Hol
e Le
ngth
(m)
gabbro
gabbro(altered)
gabbro(altered-blue quartz)
gabbro(altered-biotite)
fg-mg gabbro
surface
CrCo
(A)
Figure 5-59a. Profiles through drill hole A1-97 from the Rauhala property (Makada Lake
intrusion), showing stratigraphic variations in Co and Cr.
236
0
10
20
30
40
50
600.001 0.01 0.1 1 10
Pt/Se and Pd/Se
Dril
l Hol
e Le
ngth
(m)
Pd/Se
Pt/Se
gabbro
gabbro(altered)
gabbro(altered-blue quartz)
gabbro(altered-biotite)
fg-mg gabbro
surface(B)
Figure 5-59b. Profiles through drill hole A1-97 from the Rauhala property (Makada Lake
intrusion), showing stratigraphic variations in Pt/Se and Pd/Se ratios.
237
No Description VS From To Au Pt Pd Cu Ni S Se(m) (m) ppb ppb ppb ppm ppm wt% ppb
LLD --> 5 15 10 5.0 5.0 0.05 1001 mg gabbro 0 2.23 2.43 - - 10 58 47 0.096 1932 mg gabbro 0 4.27 4.57 - - - 84 50 0.037 -3 mg gabbro 0 6.10 6.30 - - - 36 45 0.021 2354 mg gabbro 0 7.32 7.52 - - 15 77 54 0.029 -5 mg gabbro 0 8.53 8.85 - - - 59 54 0.020 -6 mg gabbro 0 10.06 10.26 - - - 55 62 0.018 -7 mg gabbro 0 11.58 11.78 - - - 45 51 0.023 6328 mg gabbro 0 13.11 13.40 - - - 28 54 0.018 3049 mg gabbro 0 14.63 14.85 - - - 19 47 0.011 320
10 mg gabbro 0 16.46 16.66 - - - 21 50 0.016 -11 mg gabbro 0 17.68 17.88 - - - 23 51 0.013 10212 mg gabbro 0 19.20 19.40 - - - 73 80 0.041 81713 mg gabbro 0 20.42 20.62 - - - 76 55 0.032 10414 mg gabbro 0 21.64 21.84 - - - 28 69 0.022 198015 mg gabbro 0 23.77 23.97 - - - 59 53 0.023 57816 mg gabbro 0 25.30 25.50 11 - - 60 57 0.019 68617 mg gabbro 0 26.09 26.29 - - - 51 49 0.016 84518 mg gabbro 0 27.43 27.63 - - - 55 55 0.024 -19 mg gabbro 0 28.96 29.16 - - - 59 55 0.021 -20 mg gabbro 0 30.78 30.98 - - - 60 55 0.036 26921 mg gabbro 0 32.16 32.36 - - - 70 54 0.024 -22 mg gabbro 0 33.68 33.88 - - - 81 50 0.027 -23 mg gabbro 0 35.05 35.25 - - - 80 66 0.025 311
Table 5-15. Summary of chalcophile element concentrations and ratios for samples from
diamond drill hole A1-97, Rauhala property, Makada Lake intrusion, Waters Township.
Sample prefixes = WT99; VS = visible sulphide; LLD=lower limit of detection; "-
"=below detection.
238
No Description VS From To Au Pt Pd Cu Ni S Se(m) (m) ppb ppb ppb ppm ppm wt% ppb
LLD --> 5 15 10 5.0 5.0 0.05 10024 mg gabbro 0 36.27 36.47 9 - - 75 62 0.020 -25 altered gabbro <1 37.19 37.52 - - - 18 45 0.010 14526 altered gabbro <1 38.31 38.59 - - - 9 57 - 47627 altered gabbro <1 38.71 38.93 - - - 29 126 0.041 46628 altered gabbro <1 38.95 39.21 - - - 49 163 0.075 59129 altered gabbro <1 39.62 39.85 - - - 12 183 0.024 170230 altered gabbro <1 40.39 40.63 - - - 11 65 - 55531 altered gabbro <1 40.84 41.06 - - - 9 85 0.026 19532 altered gabbro <1 42.0624 42.2624 - - - 53 62 0.038 -33 altered gabbro; blue qtz 5 43.5864 43.7864 577 - - 55 60 0.016 41034 altered gabbro; blue qtz 5 45.1866 45.42 7 - - 32 65 0.022 57335 altered gabbro; blue qtz 5 46.6344 46.8344 - - - 39 71 0.028 -36 altered gabbro; blue qtz 5 48.1584 48.45 - - - 58 44 0.021 -37 altered gabbro; blue qtz 5 49.0728 49.2728 - - - 69 55 0.024 -38 altered gabbro; biotite 10 51.2064 51.4064 - - - 68 44 0.023 26739 altered gabbro; biotite 10 52.1208 52.3208 8 - - 41 49 0.019 -40 altered gabbro; biotite 10 53.9496 54.2 19 32 167 234 189 0.074 37441 altered gabbro; biotite 10 54.2544 54.4544 62 120 715 484 433 0.172 57142 altered gabbro; biotite 10 54.5592 54.7592 130 217 1033 1077 1101 0.424 113043 altered gabbro; biotite 10 54.864 55.1 9 29 28 45 96 0.019 -44 fg-mg gabbro 55.0164 55.2164 - - - 39 114 0.022 59245 fg-mg gabbro 55.4736 55.6736 10 - - 85 69 0.029 57146 fg-mg gabbro 55.9308 56.11 6 - 11 87 87 0.031 -
Table 5-15 (cont). Summary of chalcophile element concentrations and ratios for samples
from diamond drill hole A1-97, Rauhala property, Makada Lake intrusion, Waters
Township. Sample prefixes = WT99; VS = visible sulphide; LLD=lower limit of
detection; "-"=below detection.
239
Peaks in the concentration of S are coincident with the peaks in Pt-Pd-Cu-Ni, suggesting
sulphide control on the PGE; peaks in Co and Cr are also coincident with the highest
PGE-Cu-Ni mineralization. At approximately 40 m down the hole there are peaks in the
Se, S, Cu and Ni concentrations but all PGE are below the lower limits of detection. This
implies that although the magma continued to precipitate sulphides the availability of
PGE had significantly declined, having been stripped from the magma in earlier forming
sulphides (i.e. from 53.95-54.76 m). Values for S/Se within the PGE-Cu-Ni zone are
within the range of uncontaminated magmatic sulphides (Naldrett, 1981). However,
more than 20 of the samples have S/Se values that are <1000, which can be attributed to
S loss and/or preferential incorporation of Se into the sulphide, relative to S, as discussed
in Section 5.2.3. The six samples with S/Se values >5000, is probably due to the
introduction of external sulphur through local contamination.
5.10 Kukagami Lake Intrusion – Traverse
The Kukagami Lake intrusion, located about 45 km northeast of the City of Greater
Sudbury in Kelly Township, is a northwest-trending body that is exposed for more than
12 km from the southeast quadrant of Kelly Township through to Mackelcan Township
in the northwest (Figs. 1-2, 5-60, 5-61 and 5-62). Samples were collected from four areas
along the strike of the Kukagami Lake sill, encompassing seven samples from the
“Kukagami Cliff” area (Photo 4-1), located at the western “end” of the intrusion (Fig. 5-
61); 15 samples that comprise the lithogeochemical section through the central part of the
intrusion (Fig. 5-61); five samples from the Whalen showing (Kukagami Lake
occurrence; Lightfoot et al., 1993), located about 150 m east of the northern part of the
lithogeochemical section (Fig. 5-61); and, seven samples from the area of the Washagami
Lake occurrence (Fig. 5-62). A summary of the samples is provided in Table 5-16 and a
complete listing of the data is provided in Appendix 1.
5.10.1 Geology and Mineralization
Thomson and Card (1963) interpreted the Nipissing Gabbro intrusions in this region
to range from large dikes and sills to small irregularly shaped masses, mapping the
Kukagami Lake body as a sill. On the basis of PGE-Cu-Ni sulphide occurrences and
similar geochemical characteristics, Lightfoot et al. (1993) proposed that the Kukagami
Lake sill and Wanapitei intrusion (Dressler, 1982) are one contiguous sill (Fig. 5-1).
240
Figure 5-60. General geology and location of the Kukagami Lake intrusion, Kelly
Township. Specific sample location areas – Kukagami West and Kukagami East – are
outlined and shown in detail in Figures 5.10-2 and 5.10-3, respectively. Geology is after
Thomson and Card (1963). Map coordinates are UTM, NAD27-Zone17.
241
Figure 5-61. General geology and location of samples collected from the western portion
of the Kukagami Lake intrusion, Kelly Township. Also shown is the location of the
Whalen showing and the Kukagami Cliff area. Geology is after Thomson and Card
(1963). Map coordinates are UTM, NAD27-Zone17.
242
Figure 5-62. General geology and location of samples collected from the eastern portion
of the Kukagami Lake intrusion, Kelly Township. Also shown is the location of the
Washagami Lake occurrence. Geology is after Thomson and Card (1963). Map
coordinates are UTM, NAD27-Zone17.
243
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB97-102 sediment 0.070 300 82 - - - 7.000 5.000JB98-194 G (Q-H) 0.054 292 117 0.053 0.350 0.434 8.350 9.510JB98-195 G (Q-H) 0.056 267 116 - - 0.277 10.610 11.020JB98-196 G (Q-H) 0.032 181 134 - - 0.309 14.450 13.180JB98-197 G (Q-H) 0.058 243 63 - - - - 0.090JB98-198 G (Q-H) 0.085 394 155 - 0.130 - 1.310 1.330JB98-199 G (Q-H) 0.013 204 119 - - - 1.290 0.970JB98-200 GN (H-O) 0.037 261 150 - - 0.098 2.570 2.230JB98-201 G (Q-H) 0.035 212 153 - 0.130 0.096 4.100 3.200JB98-202 G (Q-H) 0.078 311 148 - - 0.142 7.730 7.560JB98-203 G (Q-H) 0.055 147 150 0.050 - 0.387 8.000 9.410JB98-204 G (Q-H) 0.009 100 147 0.056 0.150 0.407 8.540 8.720JB98-205 G (Q-H) 0.016 86 182 0.127 0.190 0.750 9.780 24.600JB98-206 G (Q-H) 0.039 155 146 0.065 0.150 0.446 10.700 10.100JB98-207 G (Q-H) 0.053 168 122 0.070 0.160 0.399 12.340 12.970
JB98-239A sediment 0.115 134 69 0.040 0.130 0.080 1.790 3.120JB97-103E G (Q-H) 0.014 na 125 0.200 - 0.500 15.000 15.000JB97-103D G (Q-H) 0.067 600 148 0.200 - 1.100 12.000 19.000JB97-103C opx gabbro 1.961 6200 2662 0.800 - 12.000 440.000 1550.000JB97-103B GN (H-O) 0.067 700 213 0.500 - 0.700 20.000 55.000JB97-103A opx gabbro 1.734 6400 2773 0.700 - 23.000 380.000 1930.000JB98-239B G (Q-H) 0.086 211 117 - - 0.310 10.400 17.240JB98-239C G (Q-H) 0.040 219 119 - - 0.280 10.590 11.100JB98-240 G (Q-H) 0.044 239 120 - - 0.290 10.610 12.120
JB98-239F G (Q-H) 0.024 180 94 na na na na naJB98-239E G (Q-H) 0.053 237 132 na na na na naJB98-239D GN (H-O) 0.087 221 120 na na na na na
JB97-18 G (Q-H) 0.060 365 150 - - - 4.366 6.156JB97-20 G (Q-H) 0.020 233 140 0.182 - 0.620 27.300 45.041JB97-14 G (Q-H) 0.050 258 160 0.230 - 1.120 32.510 119.000JB97-15 G (Q-H) 0.040 358 130 - - - 1.488 2.671JB97-16 G (Q-H) 0.080 500 180 0.240 - 1.061 28.168 109.656
JB97-19A G (Q-H) 0.040 321 220 0.170 - 0.790 17.830 68.770JB97-19B G (Q-H) 0.070 297 170 0.170 - 0.880 16.050 57.410
Table 5-16. Summary of whole-rock geochemical characteristics for samples from the
Kukagami Lake intrusion, Kelly Township. The main sample section through the
intrusion includes samples JB97-102 through to JB98-239A. "-" below lower limit of
detection; "N" = primitive mantle-normalized; "na"=not analyzed; G=gabbro;
OLGN=olivine leucogabbronorite; LG=leucogabbro; GN=gabbronorite;
opx=orthopyroxene; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-
hypersthene-corundum. Norm wt% = rock types determined on the basis of weight
percent normative minerals calculated to normative weight percent.
244
Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB97-102 1.500 73 2333 0.7 0.9 50 156 4.11JB98-194 3.650 118 1849 1.1 1.0 65 43 2.19JB98-195 2.880 104 2097 1.0 0.9 64 43 2.02JB98-196 - 111 1768 0.9 0.8 70 30 2.05JB98-197 0.820 118 2387 - 1.9 53 60 2.31JB98-198 2.500 227 2157 1.0 1.5 67 39 2.10JB98-199 2.720 138 637 0.8 1.2 66 40 2.22JB98-200 3.700 168 1418 0.9 1.1 70 30 1.98JB98-201 5.300 150 1651 0.8 1.0 72 31 1.93JB98-202 5.740 144 2508 1.0 1.0 68 40 2.02JB98-203 2.470 82 3741 1.2 0.5 72 32 2.19JB98-204 1.970 78 900 1.0 0.5 71 33 2.09JB98-205 2.630 87 1860 2.5 0.5 75 26 2.00JB98-206 3.280 88 2516 0.9 0.6 72 34 2.00JB98-207 4.510 109 3155 1.1 0.9 66 40 2.09
JB98-239A 2.230 40 8582 1.7 0.6 53 129 3.62JB97-103E 1.200 94 - 1.0 0.8 65 36 2.00JB97-103D 1.000 110 1117 1.6 0.7 68 35 2.03JB97-103C 120.000 6259 3162 3.5 2.4 65 29 1.98JB97-103B 2.000 196 957 2.8 0.9 71 29 1.85JB97-103A 120.000 5095 2710 5.1 1.8 64 30 1.87JB98-239B 2.260 77 4076 1.7 0.7 66 40 2.52JB98-239C 3.530 114 1826 1.0 1.0 65 35 2.30JB98-240 3.280 133 1841 1.1 1.1 65 38 2.19
JB98-239F na 73 1333 - 0.8 64 38 2.42JB98-239E na 112 2236 - 0.8 68 34 2.26JB98-239D na 95 3937 - 0.8 68 39 2.60
JB97-18 4.272 170 1644 1.4 1.1 67 37 2.09JB97-20 4.811 120 858 1.6 0.9 68 34 1.96JB97-14 8.010 130 1938 3.7 0.8 70 30 1.91JB97-15 2.257 160 1117 1.8 1.2 65 38 1.94JB97-16 8.586 220 1600 3.9 1.2 67 34 1.86
JB97-19A 17.090 190 1246 3.9 0.9 71 35 2.23JB97-19B 4.330 150 2357 3.6 0.9 71 29 1.89
Table 5-16 (cont). Summary of whole-rock geochemical characteristics for samples from
the Kukagami Lake intrusion, Kelly Township. The main sample section through the
intrusion includes samples JB97-102 through to JB98-239A. "-" below lower limit of
detection; "N" = primitive mantle-normalized; "na"=not analyzed; G=gabbro;
OLGN=olivine leucogabbronorite; LG=leucogabbro; GN=gabbronorite;
opx=orthopyroxene; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-
hypersthene-corundum.
245
However, on the basis of field relationships noted during the course of the current study,
it is more likely that the Kukagami Lake intrusion is contiguous with bodies in Davis
Township to the southeast, and perhaps even the Chiniguchi River intrusion in Janes
Township further to the southeast (Fig. 5-1); together these intrusive bodies appear to
form an inward-dipping arcuate shape, indicative of a cone sheet.
The Kukagami Lake sill is hosted by Gowganda Formation (argillite, quartzite) and
subordinate Lorrain Formation (arkose) sedimentary rocks (Thomson and Card, 1963),
and parallels a large Sudbury Swarm dike which extends for more than 25 km (Shellnutt,
2002). On the basis of field observations and the geology of the section through the
intrusion, the base of the intrusion is interpreted to be along the northern contact.
Locally, the Kukagami Lake section provides a near-complete cross-section through
the sill, exposing the basal contact of the intrusion in the north (Fig. 5-61; Photo 5-5a).
Samples JB98-239A and JB97-102 are used as representatives of the footwall and
hangingwall sedimentary rocks, respectively, in the sample section. From north to south,
the intrusive rocks comprise fine-grained to chilled gabbro (±quartz), medium-grained
gabbro (±magnetite), orthopyroxene gabbro (±magnetite), medium-grained gabbro,
medium-grained gabbro (±magnetite), and finally fine- to medium-grained gabbro along
the northern shore of Carafel Bay (Fig. 5-61). Pegmatitic gabbro and vari-textured
gabbro were noted in several outcrops in the region of JB98-196, JB98-197 and JB98-
198, located in the southern part of the section or in the upper portion of the sill
stratigraphy. Several samples of chilled margin gabbro (sample JB98-239A, 239B and
240) were collected from exposures near the Kukagami cliff (Fig. 5-61).
Several PGE-Cu-Ni sulphide showings occur within the Kukagami Lake intrusion,
specifically toward the western segment of the sill (Kukagami Cliff area; Fig. 5-61), the
central portion of the intrusion (Whalen showing; Fig. 5-61), and the eastern portion of
the sill (Washagami Lake occurrence; Fig. 5-62). Lightfoot et al. (1991a) reported values
of 90 ppb Au, 215 ppb Pt, 1840 ppb Pd, 3200 ppm Cu, 1650 ppm Ni, and 1.0 wt% S from
the Kukagami Cliff area and 600 ppb Au, 945 ppb Pt, 4160 ppb Pd, 8000 ppm Cu, 2800
ppm Ni, and 2.1 wt% S from the Whalen showing (Fig. 5-61; Photo 5-5b).
246
Photo 5-5. Kukagami Lake Intrusion. (A) Sharp contact between Huronian Supergroup sedimentary rocks (sediment) and fine- to medium-grained gabbro, from the northern basal contact of the intrusion. The hammer handle is about 33 cm long. (B) Medium-grained orthopyroxene gabbro from the Whalen showing (sample JB98-103A) with disseminated (ds) and blebby sulphide and very fine-grained blue quartz. The pen magnet is about 12 cm long.
247
Patchy sulphide mineralization (~1% pyrrhotite + chalcopyrite) was noted at several
locations within ~100 m of the northern contact of the intrusion, hosted by dark-
weathering, orthopyroxene gabbro. In 1999, Pacific North West Capital Corp. completed
5 diamond drill holes on the Washagami Lake occurrence, also referred to as the Davis-
Kelly property (Meyer et al., 2000); a summary of the drill results is listed in Table 5-17.
5.10.2 Major Element Variations
Gabbroic samples from the Kukagami Lake intrusion are characterized by averages
of 51.7 wt% SiO2, 0.51 wt% TiO2, 14.1 wt% Al2O3, 8.9 wt% MgO, and an Mg-number of
68. Four samples of chilled margin gabbro average 50.8 wt% SiO2, 0.55 wt% TiO2, 14.6
wt% Al2O3, 8.3 wt% MgO, and an Mg-number of 65. CIPW normative calculations were
completed on 30 of the 32 gabbroic samples collected from the Kukagami Lake sill
(Table 5-16). The majority of samples (27 of 30) classify as quartz-hypersthene-
normative (silica-oversaturated) gabbro with three samples classifying as hypersthene-
olivine-normative (silica-saturated) gabbronorite. In the field, samples described as
orthopyroxene gabbro classified mainly as CIPW gabbro with only one correlating with
CIPW gabbronorite; CIPW gabbro samples cover a range in rock types including gabbro,
vari-textured gabbro, magnetite-bearing gabbro and orthopyroxene gabbro.
With the exception of samples JB98-197, JB98-195 and JB98-194, which are
differentiated rock types within the sill, all of the intrusive rocks from the sample section
and the majority of other samples from other areas of the sill have higher Mg-number and
lower TiO2 concentrations relative to average chilled margin gabbro and relative to the
sample of chilled gabbro collected from the northern margin of the sill (Fig. 5-63).
Assuming that the average chilled margin and chilled margin samples from the Kukagami
Lake sill represent parent magma compositions, then it follows that the rocks within the
main body of the intrusion are much more primitive or less fractionated relative to
“normal” or average Nipissing Gabbro. Much of this sill consists of either massive
orthopyroxene gabbro with ~5-10% phenocrysts of hypersthene (up to 5 mm long) or
orthopyroxene-bearing gabbro with 1-5% primocrysts of orthopyroxene. The primitive
nature of these rocks relative to chilled margin gabbro supports the interpretation that
they are cumulates and that they do not represent the liquids from which the associated
chilled margin gabbro rocks crystallized.
248
DDH From To Interval 3E Cu Ni Cu+Nim m m ppm wt% wt% wt%
DK99-01 20 29.5 9.5 0.55 0.04 0.03 0.0751.2 54.53 3.33 2.66 0.31 0.19 0.5
DK99-02 16 20.5 4.5 0.55 0.04 0.03 0.0726.25 31 4.75 1.26 0.09 0.06 0.15
including 28.5 30 1.5 2.46 0.18 0.11 0.2949.1 53.5 4.4 3.93 0.44 0.3 0.74
including 49.1 52.7 3.6 4.38 0.49 0.33 0.82DK99-03 18.2 19.7 1.5 0.99 0.21 0.08 0.29
31.85 35.6 3.75 1.25 0.12 0.08 0.2DK99-05 28 37.3 9.3 0.16 0.03 0.03 0.06
40.4 41.7 1.7 0.46 0.06 0.05 0.11
Table 5-17. Summary of diamond drill core assay results from the Washagami Lake
occurrence (also referred to as the Davis-Kelly showing), Kelly Township (Meyer et al.,
2000). Diamond drilling was completed in 1999 by Pacific North West Capital Corp..
Values for 3E = Pt+Pd+Au.
249
0.3
0.4
0.5
0.6
0.7
0.8
0.9
3035404550556065707580
Mg-number
TiO
2 (w
t%) JB97-102 (HW)
JB98-194JB98-195JB98-196JB98-197JB98-198JB98-199JB98-200JB98-201JB98-202JB98-203JB98-204JB98-205JB98-206JB98-207JB98-239A (FW)Chilled Margin AvgHuronian Sediment AvgAplite Avg
fractionation
Y mt gabbro (CIPW)A gabbro (CIPW)D vt gabbro) gabbronorite (CIPW)# chilled gabbro+ sediment
vt gabbro
chilled margin
(A)
0.3
0.4
0.5
0.6
0.7
0.8
0.9
3035404550556065707580
Mg-number
TiO
2 (w
t%)
Chilled Margin AvgHuronian Sediment AvgAplite Avg
fractionation
JB98-197Y mt gabbro (CIPW)A gabbro (CIPW)D vt gabbro) gabbronorite (CIPW)# chilled gabbro+ sediment
(B)
Figure 5-63. Bivariate scatter plots of Mg-number and wt% TiO2 for rocks from the Kukagami Lake intrusion. (A) Rocks from the sample section through the intrusion. (B) All samples collected from the intrusion.
250
Variation in selected major elements are plotted against relative distance or
stratigraphic height through the intrusion (Fig. 5-64). The concentration of SiO2 shows
very little variation through the section, averaging ~51.7 wt% SiO2 and the
concentrations of TiO2 display a gradual increase through the section, with the highest
concentration of TiO2, coincident with the highest concentration of SiO2, occurring in the
upper vari-textured gabbro unit (Fig. 5-64). Mg-number shows a slight increase in the
lowermost samples, above the chilled margin, followed by a general decrease upward
through the intrusion, which is indicative of normal fractionation. The Mg-number of the
lower chilled gabbro (Mg-number = 66) approximates that of the uppermost gabbro unit
(Mg-number = 65); the latter was collected from within ~25 m of the hangingwall
sedimentary rocks (Fig. 5-61).
5.10.3 Trace and Rare-Earth Element Variations
In general, rocks from the sample section show very little variation upward through
the intrusion and disregarding the uppermost gabbro (JB98-194) and lowermost chilled
gabbro (JB98-207), there is only a very subtle upward (north to south) increase in the
ratios of (La/Sm)N, (Th/Nb)N and in concentrations of Zr and ∑REE; this suggests normal
fractionation within the sill with very little in-situ contamination.
Primitive mantle-normalized multi-element diagrams for samples from the
Kukagami Lake intrusion are shown in Figures 5-65 and 5-66. The gabbroic samples
have similar overall trace and rare-earth element abundances (~1-50 times primitive
mantle) with moderate LILE enrichment (~1-50 times primitive mantle), an average of
~2.1 (La/Sm)N, and weakly enriched HREE (~1-6 times primitive mantle); sample JB98-
197, which is a differentiated gabbro from the upper stratigraphy of the intrusion, shows
the highest overall REE abundance. All of the gabbroic examples, excepting sample
JB98-197, display lower overall REE abundances relative to the average chilled margin
gabbro of Lightfoot and Naldrett (1996). All of the gabbroic samples, including JB98-
197, display pronounced negative Nb+Ta anomalies and moderate to strongly negative
P* and Ti* anomalies, which is typical of other Nipissing Gabbro intrusions (Lightfoot
and Naldrett, 1996).
251
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
45 50 55 60 65 70 75 80
SiO2 (wt) and Mg-number
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
sediment NORTH
SOUTH
mt gabbro (G)
gabbro (G)
gabbro (G)
mt gabbro (G)
gabbro (G)
gabbro (GN)
opx gabbro (G)
chilled gabbro (G)
vt gabbro (G)
SiO2 Mg-number
Figure 5-64a. Profiles through the Kukagami Lake intrusion showing stratigraphic
variations in Mg-number and SiO2. The relative vertical scale is in metres.
252
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
TiO2 (wt%)
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
sedimentNORTH
SOUTH
mt gabbro (G)
gabbro (G)
gabbro (G)
mt gabbro (G)
gabbro (G)
gabbro (GN)
opx gabbro (G)
chilled gabbro (G)
vt gabbro (G)
Figure 5-64b. Profile through the Kukagami Lake intrusion showing stratigraphic
variations in TiO2. The relative vertical scale is in metres.
253
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tleJB97-102 (HW)
JB98-194
JB98-195
JB98-196
JB98-197
JB98-198
JB98-199
JB98-200
JB98-201
JB98-202
JB98-203
JB98-204
JB98-205
JB98-206
JB98-207
JB98-239A (FW)
Chilled Margin Avg
(A) g mt gabbro (CIPW)A gabbro (CIPW)D vt gabbro) gabbronorite (CIPW)# chilled gabbro+ sediment
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-103E
JB97-103D
JB97-103C
JB97-103B
JB97-103A
Chilled Margin Avg
(B)A gabbro (CIPW)) gabbronorite (CIPW)
Figure 5-65. Primitive mantle-normalized multi-element diagrams for rock samples from the Kukagami Lake intrusion, Kelly Township. (A) Sample Section through sill. (B) Detailed sampling from Whalen sulphide showing. Mantle normalizing values are from McDonough and Sun (1995).
254
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-207
JB98-239B
JB98-239C
JB98-240
Chilled Margin Avg
(A)
# chilled gabbro
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-194JB98-195JB98-196JB98-197JB98-198JB98-199JB98-200JB98-201JB98-202JB98-203JB98-204JB98-205JB98-206JB98-207JB97-103EJB97-103DJB97-103CJB97-103BJB97-103AJB98-239BJB98-239CJB98-240JB98-239FJB98-239EJB98-239DJB97-18JB97-20JB97-14JB97-15JB97-16JB97-19AJB97-19BChilled Margin Avg
(B)g mt gabbro (CIPW)A gabbro (CIPW)D vt gabbro) gabbronorite (CIPW)# chilled gabbro
Figure 5-66. Primitive mantle-normalized multi-element diagrams for rocks from the Kukagami Lake intrusion. (A) Chilled margin gabbro. (B) All gabbroic rocks. Mantle normalizing values are from McDonough and Sun (1995).
255
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-194JB98-195JB98-197JB98-198JB98-202JB98-203JB98-207JB97-103DJB97-103CJB97-103BJB97-103AJB98-239BJB98-239EJB98-239DJB97-18JB97-16JB97-19BChilled Margin Avg
(C)g mt gabbro (CIPW)A gabbro (CIPW)D vt gabbro) gabbronorite (CIPW)# chilled gabbro
(>0.05 wt% S)
Figure 5-66. Primitive mantle-normalized multi-element diagrams for rocks from the
Kukagami Lake intrusion, Kelly Township. Samples plotted are gabbroic rocks with
elevated sulphur (>0.05 wt% S). Mantle normalizing values are from McDonough and
Sun (1995).
256
5.10.4 Chalcophile (PGE, Cu, Ni) Element Variations
As described earlier, there are several sulphide showings containing anomalous
PGE-Cu-Ni mineralization within the Kukagami Lake sill (Figs. 5-61 and 5-62). Five
samples were collected from the immediate area of the Whalen showing (Fig. 5-61) with
maximum values of 120 ppb Au, 440 ppb Pt, 1930 ppb Pd, 5095 ppm Cu, 2773 ppm Ni,
and ~2.0 wt% S. Two samples were collected from the immediate area of the
Washagami Lake occurrence (Fig. 5-62) with maximum values of 17 ppb Au, 18 ppb Pt,
69 ppb Pd, 190ppm Cu, 220 ppm Ni, and 0.07 wt% S. In this area, the highest precious
metals values are from sample JB97-14 (orthopyroxene gabbro or CIPW gabbro), located
about 200 m northwest of the Washagami Lake occurrence, which contains 8 ppb Au, 33
ppb Pt, 119 ppb Pd, 130 ppm Cu, 160 ppm Ni, and 0.05 wt% S.
Selected chalcophile elements and ratios are plotted against relative distance through
the intrusion in Figure 5-67. For the most part the concentrations of Pt, Pd, Cu, Ni, and
S, along with the ratios of Cu/Ni and Pd/Pt, show no systematic variation through this
section of the sill and the gabbroic samples have S/Se ratios (~637-3741) that are
generally indicative of uncontaminated magmatic sulphide (Naldrett, 1981). However, of
particular interest are the ratios of Pt/Se, Pd/Se and Cu/Pd which are highest in the
lowermost and uppermost gabbroic units, peaking at ~600 m (Fig. 5-67). These trends
suggest that, as at the Charlton Lake sill (see Section 5.5.4), there was co-precipitation of
sulphides in the magma along two sulphide precipitation fronts; one moving downward
from the upper part of the sill and the other moving upward from the lower part of the
sill.
Primitive mantle-normalized PGE and chalcophile element diagrams (recalculated to
metals in 100% sulphide) are shown in Figures 5-68 and 5-69. All of the gabbroic
samples from the Kukagami Lake intrusion are characterized by positive slopes with the
Pt-Pd-Au-Cu (~600-20,000 times primitive mantle) portion elevated relative to the Ni-Ir-
Ru-Rh portion (~7-300 times primitive mantle). Although much lower in chalcophile
abundance, the sample of sedimentary rock also features a positive slope and parallels the
patterns of the gabbroic rocks. Most of the gabbroic samples show a peak in Pd, have
Ni/Ir values that are close to 1 or greater (negative slopes) and display profiles that are
similar to average chilled margin and average flood basalt.
257
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
0.01 0.1 1 10 100 1000 10000 100000 1000000 10000000
Concentration and Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
sediment NORTH
SOUTH
mt gabbro (G)
gabbro (G)
gabbro (G)
mt gabbro (G)
gabbro (G)
gabbro (GN)
opx gabbro (G)
chilled gabbro (G)
vt gabbro (G)
Pd (ppb)
Pt (ppb)
(A)
S (ppb)
Ni (ppm) Cu (ppm) S/Se
Cu/Pd
Figure 5-67a. Profiles through the Kukagami Lake intrusion sample section, showing
stratigraphic variations in Pd, Pt, Ni, Cu, S/Se, Cu/Pd and S. The arrows show the
direction of the sulphide precipitation front. The relative vertical scale is in metres.
258
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
0.0001 0.001 0.01 0.1 1 10
Ratio
Rel
ativ
e D
ista
nce
(not
to sc
ale)
sediment
sedimentNORTH
SOUTH
mt gabbro (G)
gabbro (G)
gabbro (G)
mt gabbro (G)
gabbro (G)
gabbro (GN)
opx gabbro (G)
chilled gabbro (G)
vt gabbro (G)
Pt/Se
Pd/PtCu/Ni
Pd/Se
(B)
Figure 5-67b. Profiles through the Kukagami Lake intrusion sample section, showing
stratigraphic variations in Pt/Se, Pd/Se, Cu/Ni and Pd/Pt. The arrows show the direction
of the sulphide precipitation front. The relative vertical scale is in metres.
259
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-194
JB98-201
JB98-203
JB98-204
JB98-205
JB98-206
JB98-207
JB98-239A (FW)
Chilled Margin Avg
Flood Basalt Avg
g mt gabbro (CIPW)A gabbro (CIPW)# chilled gabbro+ sediment
(A)
Figure 5-68a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from samples collected through
the Kukagami Lake intrusion. Data for average chilled margin is from this study; data for
average flood basalt is from Naldrett (1981). Mantle normalizing values are from Barnes
et al. (1988) and McDonough and Sun (1995).
260
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB97-103E
Chilled Margin Avg
Flood Basalt Avg
A gabbro (CIPW)
(B)
Figure 5-68b. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from detailed sampling at the
Whalen sulphide showing, Kukagami Lake intrusion. Data for average chilled margin is
from this study; data for average flood basalt is from Naldrett (1981). Mantle
normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
261
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-207
JB98-239B
JB98-239C
JB98-240
Chilled Margin Avg
Flood Basalt Avg
# chilled gabbro
(A)
Figure 5-69a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from chilled margin gabbro,
Kukagami Lake intrusion. Data for average chilled margin is from this study; data for
average flood basalt is from Naldrett (1981). Mantle normalizing values are from Barnes
et al. (1988) and McDonough and Sun (1995).
262
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-194
JB98-203
JB98-207
JB98-239B
JB97-16
JB97-19B
Chilled Margin Avg
Flood Basalt Avg
(>0.0.5 wt% S)
A gabbro (CIPW)# chilled gabbro
(B)
Figure 5-69b. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides in gabbroic rocks with elevated
sulphur (>0.05 wt% S), Kukagami Lake intrusion. Data for average chilled margin is
from this study; data for average flood basalt is from Naldrett (1981). Mantle
normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
263
5.11 Manitou Lake Intrusion – Traverse
The sample section through the Manitou Lake intrusion, located about 65 km
northeast of the City of Greater Sudbury, covers a relatively small portion of a much
larger body of Nipissing Gabbro that extends for more than 20 km to the northeast into
Scholes Township, more than 12 km to the northwest into Afton Township, and more
than 12 km to the southeast into Pardo and Hobbs townships where it terminates against
the Grenville Front Boundary Fault (Figs. 1-2 and 5-1). The sample suite consists of nine
samples, collected immediately west of Manitou Lake in Clement Township along
Highway 805, which provides numerous exposures of gabbroic rock (Fig. 5-70). From
north to south the Manitou Lake section exposes homogenous medium-grained gabbro.
A summary of the samples is provided in Table 5-18 and a complete listing of the data is
provided in Appendix 1.
5.11.1 Geology and Mineralization
The Manitou Lake intrusion is relatively undifferentiated, consisting mainly of
medium-grained two-pyroxene gabbro, with fine-grained gabbro (chill?) noted within 3-
7.5 m of the contact, and occasional patches of coarse-grained gabbro and pods of
pegmatitic gabbro (Meyn, 1977). The intrusion, as described by Meyn (1977), comprises
seven sill-like bodies within Afton, Scholes, Macbeth and Clement townships that are in
sharp contact with Gowganda Formation sedimentary rocks and in intrusive contact
(inferred) with Archaean volcanic and sedimentary rocks. The Manitou Lake intrusion
may be contiguous with the Chiniguchi River intrusion, located ~20 km to the south-
southeast in Janes Township (Dressler, 1979), and connected by Nipissing Gabbro rocks
that are apparently continuous through MacBeth (Meyn, 1977) and McNish (Dressler,
1979) townships (Fig. 5-1). Meyn (1977) also described brecciated contacts consisting of
sediment fragments hosted by finer-grained gabbro, and centimetre- to decametre-scale
fragments of sedimentary rocks hosted completely within gabbro. On the basis of
geochemical analyses and the presence of these fragments, Meyn (1977) suggested that
the Nipissing Gabbro was contaminated from interaction with the surrounding
sedimentary rocks.
264
Figure 5-70. General geology and location of the sample section for the Manitou Lake
intrusion, Clement Township. Geology after Meyn (1977).
265
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB97-32 OLGN (N-O) 0.070 121 95 - - - - -JB97-31 G (Q-H) 0.060 233 38 - - - - -JB97-30 G (Q-H) 0.070 302 110 0.178 - 0.275 2.323 7.314JB97-29 G (Q-H) 0.040 277 100 9.820 2.770 4.520 4.020 4.420JB97-28 G (Q-H) 0.070 311 110 - - - - -JB97-27 G (Q-H) 0.060 293 120 - - - 0.500 0.410JB97-26 G (Q-H) 0.070 309 110 - - - 2.363 3.271JB97-25 G (Q-H) 0.050 290 110 - - - 1.356 2.500JB97-24 G (Q-H) 0.020 155 100 - - - - 1.930Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB97-32 - 51 5785 - 0.5 48 149 1.08JB97-31 6.444 40 2575 - 1.1 34 87 1.01JB97-30 2.329 140 2318 3.1 1.3 60 43 1.00JB97-29 3.220 150 1444 1.1 1.5 58 44 0.93JB97-28 - 160 2251 - 1.5 59 46 0.90JB97-27 3.150 150 2048 0.8 1.3 63 37 0.85JB97-26 2.847 160 2265 1.4 1.5 60 38 0.91JB97-25 3.210 150 1724 1.8 1.4 61 38 0.96JB97-24 1.689 150 1290 - 1.5 58 44 0.94
Table 5-18. Summary of whole-rock geochemical characteristics for samples from the
Manitou Lake intrusion, Clement Township. "-" below lower limit of detection; "N" =
primitive mantle-normalized; "na"=not analyzed; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-
O=hypersthene-olivine; Q-H-C=quartz-hypersthene-corundum; N-O=nepheline-olivine.
Norm wt% = rock types determined on the basis of weight percent normative minerals
calculated to normative weight percent.
266
The intrusion is interpreted to be flat-lying (sill-like) on Archaean sedimentary and
volcanic rocks and Gowganda Formation with preserved thicknesses, estimated from
diamond drill hole intersections, ranging from 45 m to 360 m, with variability in
thicknesses attributed to block-faulting (Meyn, 1977).
There are no known sulphide occurrences in the immediate area of the sample
section, although there are several small sulphide (chalcopyrite-pyrite) showings
documented within the larger intrusive body (Meyn, 1977). This sample suite was
collected mainly to provide background values from what appears to be an extremely
undifferentiated intrusion in proximity to Archaean rocks.
5.11.2 Major Element Variations
CIPW normative calculations were completed on the nine samples from the Manitou
Lake section (Table 5-18). Eight of the nine samples classify as quartz-hypersthene-
normative (silica-oversaturated) gabbro. One sample (JB97-32) classifies as a nepheline-
olivine-normative (silica-undersaturated) olivine leucogabbronorite with 19.7%
normative olivine, 8% normative diopside, and 1% normative nepheline, suggesting a
slightly more alkalic gabbro relative to typical sub-alkaline Nipissing Gabbro (see
Appendix 1).
5.11.3 Trace and Rare-Earth Element Variations
Primitive mantle-normalized multi-element diagrams for rocks from the Manitou
Lake section are shown in Figure 5-71. With the exception of sample JB97-32, the
uppermost gabbro, all of the gabbroic rocks show similar trace and rare-earth element
patterns and abundances, with the seven lowermost samples clustering around average
chilled margin gabbro (~1-50 times primitive mantle). These eight samples also display
negative Nb+Ta, P* and Ti* anomalies and moderate LILE enrichment, which are typical
features of Nipissing Gabbro magmas. The pattern of sample JB97-32 is quite different
than that of the other samples, having unusually low Rb and Th values, a positive Sr
peak, and exhibiting positive P* and Ti* anomalies.
267
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-32 (S)
JB97-31
JB97-30
JB97-29
JB97-28
JB97-27
JB97-26
JB97-25
JB97-24 (N)
Chilled Margin Avg
Huronian Sediment Avg
Aplite Avg (PL)
A gabbro (CIPW)) olivine leucogabbronorite (CIPW)
Figure 5-71. Primitive mantle-normalized multi-element diagrams for rock samples from
the sample section in the Manitou Lake intrusion, Clement Township. Values for
average chilled margin gabbro (this study), average Huronian Sedimentary rocks (this
study) and average aplite (Lightfoot and Naldrett, 1996) are shown for comparison.
Mantle normalizing values are from McDonough and Sun (1995).
268
5.11.4 Chalcophile (PGE, Cu, Ni) Element Variations
None of the samples have visible sulphide and are characterized by average
concentrations of 0.06 wt% S, 128 ppm Cu, and 99 ppm Ni. The highest concentrations
of Pt+Pd are from samples JB97-29 (~8.4 ppb Pt+Pd; 1.1 Pd/Pt; 1.5 Cu/Ni) and JB97-30
(~9.6 ppb Pt+Pd; 3.2 Pd/Pt; 1.3 Cu/Ni). Only 1 sample (JB97-29) analyzed greater than
the lower limits of detection for Ir, Ru, Rh, Pt, Pd and Au. Except for sample JB97-32
(S/Se = 5785) , all of the S/Se ratios plot within the range (1000-5000) of uncontaminated
magmatic sulphide (Naldrett, 1981) and all of the samples, except JB97-27, have Pd/Se
ratios which are indicative of second-stage (fertile) magmas. Elevated values for Cu/Pd
(>>19,000) suggest that these rocks underwent sulphide segregation early on, resulting in
loss of Pd relative to Cu (Barnes et al., 1988; Prendergast and Keays, 1989; Hoatson and
Keays, 1989), which attests to the barren nature of these rocks.
5.12 Chiniguchi River Intrusion - Detail
The Chiniguchi River intrusion is located in Janes Township, about 50 km northeast
of the City of Greater Sudbury (Figs. 1-2 and 5-1). Dressler (1979) mapped and
described the Chiniguchi River intrusion, and other intrusions in the area, as irregularly
shaped or sill-like bodies (Figs. 5-1 and 5-72). Samples were collected from four areas
within the Chiniguchi River intrusion, encompassing 26 samples from the immediate area
of the Jackie Rastall (Rastall) occurrence, two samples from the KTO showing, five
samples from the NKTO showing, one sample from the northeast portion of the intrusion,
and one sample from the chilled margin of the intrusion, west of the Rastall occurrence
(Fig. 5-72). One sample was collected from the Sargesson Lake occurrence (Sargesson
Lake intrusion), located about 3.5 km to the east (Fig. 5-72). A summary of the samples
is provided in Table 5-19 and a complete listing of the data is provided in Appendix 1.
5.12.1 Geology and Mineralization
The Chiniguchi River intrusion, the largest continuous body of Nipissing Gabbro in
Janes Township, has an irregular shape with thicknesses, derived from historic diamond
drill hole intersections and current field observations, ranging from a few metres near the
contacts to 767 m within the central parts of the intrusion (Dressler, 1979).
269
Figure 5-72. General geology and location of rock samples from the Chiniguchi River
and Sargesson Lake intrusions, Janes Township. Geology after Dressler (1979).
270
Sample CIPW S Se Ni Ir Ru Rh Pt PdNorm wt% wt% ppb ppm ppb ppb ppb ppb ppb
JB98-224 G (Q-H) 0.059 222 122 0.069 - 0.207 9.530 10.720JB97-40A G (Q-H) 0.090 362 120 - - 0.250 - 1.910JB97-40B G (Q-H) 0.970 4892 650 0.170 - 1.000 3.260 5.920JB97-41A G (Q-H) 0.120 620 170 - - - - 2.260JB97-41B G (Q-H) 1.180 5201 850 0.199 - 0.160 4.992 7.777JB97-41C G (Q-H) 0.120 425 150 - - - - 3.364JB97-42A G (Q-H) 0.110 524 160 - - - - -JB97-42B G (Q-H) 1.860 9892 1300 0.310 1.150 0.750 7.100 9.130JB97-67 G (Q-H) 0.032 152 42 - - - 17.000 32.000
JB97-106A G (Q-H) 0.065 400 124 - - 1.100 21.000 38.000JB97-106C G (Q-H) 0.039 400 117 0.200 - 0.700 12.000 20.000JB97-43A G (Q-H) 3.500 21450 5400 2.943 4.998 - 798.710 7223.970JB97-43B G (Q-H) 0.040 201 140 - - 0.610 10.370 20.260JB97-43C G (Q-H) 2.710 16732 4300 1.300 7.190 12.280 284.500 1577.320JB97-43D G (Q-H) 0.390 2757 720 0.250 1.110 1.190 35.450 80.030JB97-95 G (Q-H) 0.450 3525 868 - - - 35.110 66.090JB97-96 - 3.020 18285 4941 1.320 3.770 1754.750 345.100 7135.610
JB97-106B G (Q-H) 0.049 400 121 0.200 - 0.200 11.000 18.000JB97-107 G (Q-H) 0.044 200 178 0.200 - 0.900 28.000 61.000JB97-108 G (Q-H) 0.035 500 149 0.200 - 0.600 11.000 15.000JB97-109 LG (Q-H) 5.323 35190 10560 2.400 - 23.000 1300.000 4560.000JB97-104 G (Q-H) 0.059 500 190 - - 0.600 11.000 6.000JB97-105 G (Q-H) 0.022 200 135 0.500 - 1.400 30.000 40.000JB97-87A G (Q-H) 0.027 204 58 na na na 12.000 25.000JB97-87B G (Q-H) 0.121 640 218 na na na 53.000 335.000JB97-87C G (Q-H) 1.780 8602 3029 na na na 429.000 2750.000JB97-87D G (Q-H) 3.183 15941 4995 na na na 549.000 3218.000JB97-87E G (Q-H) 2.169 12458 3535 na na na 503.000 3364.000JB97-87F G (Q-H) 2.341 11944 3698 na na na 423.000 2438.000JB97-87G G (Q-H) 1.780 8456 2284 na na na 283.000 1541.000JB97-87H G (Q-H) 1.826 8640 2790 na na na 285.000 1623.000JB97-87I G (Q-H) 1.117 5426 1626 na na na 160.000 905.000JB97-87J G (Q-H) 0.716 4700 1014 na na na 126.000 627.000JB97-87K G (Q-H) 0.097 568 161 na na na 17.000 51.000JB97-115* G (Q-H) 0.770 5683 1116 0.255 0.380 1.012 101.000 116.600
Table 5-19. Summary of whole-rock geochemical characteristics for samples from the Chiniguchi River intrusion, Janes Township. One sample (JB97-115) is from the Sargesson Lake intrusion. *sample from Sargesson Lake occurrence; "-" below lower limit of detection; "N" = primitive mantle-normalized; "na"=not analyzed; G=gabbro; OLGN=olivine leucogabbronorite; LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-hypersthene-corundum. Norm wt% = rock types determined on the basis of weight percent normative minerals calculated to normative weight percent.
271
Sample Au Cu S/Se Pd/Pt Cu/Ni Mg# ∑REE (La/Sm)N
ppb ppm ppmJB98-224 4.730 114 2658 1.1 0.9 60 46 1.80JB97-40A 2.440 160 2486 - 1.3 65 33 2.08JB97-40B 21.030 2300 1983 1.8 3.5 61 33 1.96JB97-41A 4.006 520 1935 - 3.1 66 36 2.16JB97-41B 19.907 3000 2269 1.6 3.5 64 25 2.05JB97-41C 2.275 240 2824 - 1.6 69 28 2.07JB97-42A 4.650 430 2099 - 2.7 68 25 2.07JB97-42B 28.210 4900 1880 1.3 3.8 61 24 1.99JB97-67 1.000 94 2105 1.9 2.2 71 26 1.90
JB97-106A 2.200 90 1625 1.8 0.7 67 34 2.13JB97-106C 1.900 86 975 1.7 0.7 64 38 2.18JB97-43A 462.714 13000 1632 9.0 2.4 56 29 2.02JB97-43B 3.790 110 1990 2.0 0.8 67 37 1.98JB97-43C 352.750 11000 1620 5.5 2.6 58 28 1.94JB97-43D 45.920 1600 1415 2.3 2.2 71 25 1.86JB97-95 44.370 1908 1277 1.9 2.2 70 22 1.51JB97-96 404.250 13069 1652 20.7 2.6 29 2.00
JB97-106B 2.700 71 1225 1.6 0.6 65 35 2.18JB97-107 3.700 129 2200 2.2 0.7 72 24 2.02JB97-108 0.800 87 700 1.4 0.6 69 28 1.91JB97-109 720.000 17080 1513 3.5 1.6 46 52 3.10JB97-104 11.000 250 1180 0.5 1.3 73 22 1.93JB97-105 1.800 77 1100 1.3 0.6 72 22 1.91JB97-87A 3.000 87 1324 2.1 1.5 66 36 2.06JB97-87B 33.000 660 1891 6.3 3.0 65 36 2.04JB97-87C 261.000 7031 2069 6.4 2.3 59 32 2.07JB97-87D 538.000 9458 1997 5.9 1.9 56 30 1.93JB97-87E 455.000 10301 1741 6.7 2.9 59 31 2.16JB97-87F 410.000 9468 1960 5.8 2.6 58 32 2.09JB97-87G 337.000 6227 2105 5.4 2.7 61 30 2.01JB97-87H 279.000 5891 2113 5.7 2.1 62 29 1.99JB97-87I 160.000 3769 2058 5.7 2.3 65 29 2.16JB97-87J 156.000 3072 1523 5.0 3.0 66 29 2.07JB97-87K 15.000 341 1708 3.0 2.1 68 32 2.06JB97-115* 157.300 3217 1355 1.2 2.9 66 32 1.97
Table 5-19 (cont). Summary of whole-rock geochemical characteristics for samples from the Chiniguchi River intrusion, Janes Township. One sample (JB97-115) is from the Sargesson Lake intrusion. *sample from Sargesson Lake occurrence; "-" below lower limit of detection; "N" = primitive mantle-normalized; "na"=not analyzed; G=gabbro; OLGN=olivine leucogabbronorite; LG=leucogabbro; GN=gabbronorite; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-hypersthene-corundum.
272
The deepest drill-indicated portion of the intrusion is located in the area of samples 40A
and 40B (Fig. 5-72). Dressler (1979) interpreted the variations in preserved thicknesses
to be the result of either folding of a tabular, sill-like body or the primary shape of an
oblong lopolith-like intrusion. The Chiniguchi River intrusion and its extensions toward
the north and southwest are hosted by Gowganda Formation (greywacke, quartz arenite,
arkose, conglomerate) sedimentary rocks (Dressler, 1979). The Sargesson Lake
intrusion, interpreted to be a satellite intrusion emanating from the Chiniguchi River
intrusion, is hosted by Lorrain Formation (quartz arenite, arkose) sedimentary rocks
which stratigraphically overly the Gowganda Formation; this suggests that the Sargesson
Lake intrusion is located stratigraphically “above” the Chiniguchi River intrusion. A
large Sudbury Swarm dike cuts through the central region of the Chiniguchi Lake
intrusion, striking northwest through the area of the Kukagami Lake and Rathbun Lake
intrusions (Fig. 5-1).
The most common rock types in the Chiniguchi River intrusion are medium-grained
gabbro (locally variable to leucogabbro) and medium-grained orthopyroxene gabbro.
Other rock types, typical of Nipissing Gabbro intrusion, were also noted including vari-
textured gabbro and pegmatitic gabbro; the latter commonly contains bleb chalcopyrite
and pyrrhotite but has only anomalous PGE concentrations (<100 ppb 3E). Contacts with
the Huronian sedimentary rocks are typically sharp, with a chilled to fine-grained gabbro
extending no more than one metre into the main intrusive body; rarely, fragments of
sedimentary rocks were observed in chilled margin gabbro (Photo 5-6a).
Several PGE-Cu-Ni sulphide showings occur within the intrusive bodies in Janes
Township; the two most significant are the Rastall and Sargesson Lake occurrences (Fig.
5-72). At the Rastall occurrence, work by Goldwright Explorations Inc. and Pacific
North West Capital Corp. between 1998 and 2000 included surface trenching and
sampling, and diamond drilling (Jobin-Bevans et al., 1999; Meyer et al., 2000, 2001).
The Rastall occurrence consists of a series of trenches and stripped areas that
intermittently expose sulphide mineralization over a northeast-trending (30°) strike length
of ~500 m (Fig. 5-73). Exposed surface widths of sulphide mineralization range 1-22 m
and are widest in Trench 1 (Photo 5-6b), which is centrally located in the 500 m long
mineralized zone (Fig. 5-73). In general, sulphide mineralization is dominated by
273
chalcopyrite (chalcopyrite to pyrrhotite to pentlandite of 4:2:1), ranges from 1% to 10%
total sulphide and is hosted by medium-grained, massive, orthopyroxene-bearing (1-10%
hypersthene) gabbro. The orthopyroxene-bearing gabbro unit is in gradational contact
with a gabbro unit to the east and is within about 10-50 m of the footwall gabbro-
sediment contact to the west. At surface, the footwall contact of the gabbroic body dips
at about 30-45° southeast and based on the drilling results, shallows to about 25° down-
dip of the surface showings (Fig. 5-74). Surface exposures of semi-massive
mineralization occur as small (<2.0 m diameter) pods rich in chalcopyrite, pyrrhotite and
pentlandite (Fig. 5-7a). Distribution of these pods may be in part structural, whereby
disseminated sulphides have become concentrated along localised fractures and/or faults
and/or joint planes and/or contacts (Photo 5-7b). Sulphide breccia, consisting of
fragments of sedimentary rocks and gabbroic rocks cemented by a mixture of fine-
grained carbonate and chalcopyrite, have been noted in several drill intersections (Photo
4-6).
In addition to diamond drilling, detailed surface sampling using continuous channel
samples was completed by Pacific North West Capital Corp. in 1998. A summary of
results from the diamond drilling and surface channel sampling programs are provided in
Tables 5-20 and 5-21, respectively. In reference to Table 5-21, samples C, D and E were
taken across a northeast-trending gabbro-sediment contact that is exposed in Trench 4
(Fig. 5-73); sample C is located about 9.25 m southeast of sample B, sample D about 0.6
m southwest of sample C, and sample E about 1.5 m southwest of sample C.
Pacific North West Capital Corp. also completed several diamond drill holes at the
Sargesson Lake occurrence, intersecting anomalous PGE-Cu-Ni values over 10’s of
metres (Meyer et al., 2000); a summary of the drill results is provided in Table 5-22.
Sulphide mineralization (chalcopyrite ≈ pyrrhotite > pentlandite) ranges from 1-5% total
sulphide and is as at the Rastall occurrence, hosted by medium-grained, massive,
orthopyroxene-bearing gabbro and gabbro. The orthopyroxene gabbro unit is gradational
into gabbro-leucogabbro toward the southeast and this sulphide-bearing unit occurs
within about 50 m of the footwall gabbro-sediment contact to the northwest. On the basis
of diamond drilling, the footwall contact (northwest) of the gabbroic body dips at about
30-45° southeast.
274
Photo 5-6. Chiniguchi River Intrusion. (A) Fragments of Huronian sedimentary rocks in very-fine-grained to chilled margin gabbro near Trench 4 at the Rastall occurrence, Janes Township. The Canadian 25 cent piece is about 2.2 cm in diameter. (B) Exposed sulphide mineralization (gossan) of Trench 1 at the Rastall occurrence; the sulphides are hosted by orthopyroxene gabbro and gabbro. The photo was taken looking toward the west and the trend of mineralization is from left to right. The surface exposure is about 25 m wide.
275
Figure 5-73. Schematic map of the Rastall property (Janes Township) showing the
locations of drill holes (selected projections and collars), trenches, the contact between
the Nipissing Gabbro intrusion and sedimentary country rocks, and assay values from
drill hole intersections. The cross-section in Figure 5.12-3 is constructed from drill holes
JR99-01, 06 and 11. The composite section examined in Section 5.13 is from drill holes
JR99-01 and 06.
276
Figure 5-74. Schematic drill hole cross-section (looking ~north) through the area of drill
holes JR99-01, 06 and 11 at the Rastall property, Janes Township. The location of
Trench 1 and the general geology and mineralization intersected in the drill holes is also
shown. The composite section examined in Section 5.13 uses data from drill holes JR99-
01 and 06. The location of this drill section is shown in Figure 5.12-2.
277
5.12.2 Major Element Variations
Samples of gabbroic rock from the Chiniguchi River intrusion are characterized by
averages of 48.9 wt% SiO2, 0.46 wt% TiO2, 13.8 wt% Al2O3, 8.6 wt% MgO, and Mg-
number of 64; the sample (JB97-115) from the Sargesson Lake intrusion is characterized
by 49.9 wt% SiO2, 0.45 wt% TiO2, 13.4 wt% Al2O3, 9.0 wt% MgO, and Mg-number of
66. Gabbroic samples from the Chiniguchi River intrusion with high S (>0.05 wt% S)
are characterized by averages (n=26) of 49.0 wt% SiO2, 0.45 wt% TiO2, 13.5 wt% Al2O3,
8.4 wt% MgO, and Mg-number of 63 and samples with low S (<0.05 wt% S) are
characterized by averages (n=8) of 50.2 wt% SiO2, 0.47 wt% TiO2, 14.4 wt% Al2O3, 8.6
wt% MgO, and Mg-number of 68. CIPW normative calculations were completed on 34
of the 35 samples and these are summarized in Table 5-19. With the exception of sample
JB97-109 which classifies as a quartz-hypersthene-normative leucogabbro, all of the
samples classify as quartz-hypersthene-normative (silica-oversaturated) gabbro.
Drill Hole Location From To Int. 3E Cu Nim m m ppm wt% wt%
JR99-01 ~50 m east of 35 50.05 15.05 3.1 1.08 0.27Trench 1
including -- -- -- 4.64 3.93 1.68 0.26JR99-11 same collar as 32.52 48.68 16.16 2.15 0.64 0.27
JR99-01including -- -- -- 5.67 3.07 0.7 0.31JR99-06 ~30 m south and 10 m east of Trench 1 9.9 23.91 14.01 2.07 0.84 0.35
including -- -- -- 2.4 4.45 0.87 0.47JR99-02 ~0.5 m northwest of channel sample C 7.78 11 3.22 2.49 1.34 0.65
including -- -- -- 0.64 5.25 3.37 1.67JR99-03 ~10 m north of 0 8.68 8.68 4.45 0.69 0.44
JR99-02including -- -- -- 3.06 9.03 1.2 0.91JR99-08 ~30 m south of 35.83 37.37 1.55 6.71 0.35 1.1
JR99-03 Table 5-20. Summary of drill core assay results from diamond drilling by Pacific North West Capital Corp. (1999) at the Rastall property in the Chiniguchi River intrusion, Janes Township. Results are from Jobin-Bevans et al. (1999). Values for 3E = Pt+Pd+Au and Int. = interval.
278
Location Interval Pd Pt Au 3E Cu Nim ppm ppm ppm ppm wt% wt%
Trench 1 13.34 3.52 0.44 0.4 4.36 1.04 0.42including 5.8 -- -- -- 5.08 -- --Trench 10 4.87 1.07 0.19 0.18 1.44 0.33 0.1Trench 4 2.74 2.92 0.62 0.18 3.72 0.51 0.36
(sample A)Trench 4 4.97 3.42 0.73 0.27 4.42 0.55 0.24
(sample B)Trench 4 0.53 31.2 17.2 1.3 49.7 3.41 0.4
(sample C)Trench 4 2.8 13.4 6.2 2.2 21.8 0.61 0.24
(sample D)including 0.8 61.5 18.9 3.2 83.6 1.63 0.08including 0.4 78.4 18.5 5.5 102.4 -- --Trench 4 2.63 -- -- -- 5.2 -- --
(sample E)
Table 5-21. Summary of surface channel sample assay results, collected by Pacific North
West Capital corp. (1998), from the Rastall property in the Chiniguchi River intrusion,
Janes Township. Results are from Jobin-Bevans et al. (1999). Sample B is located about
3.25 m northeast and parallel to sample A – see text for description. Values for 3E =
Pt+Pd+Au.
279
Drill Hole From To Interval 3E Cu Ni Cu+Nim m m ppm wt% wt% wt%
SL99-01 15.1 17 1.9 0.37 0.34 0.12 0.46SL99-01 30 31.2 1.2 1.34 0.19 0.13 0.32SL99-02 25 28.7 3.7 0.41 0.31 0.11 0.42SL99-02 31.25 39.3 8.05 0.33 0.26 0.09 0.35SL99-02 41.45 44 2.55 0.66 0.21 0.13 0.34SL99-03 23 26.55 3.55 0.31 0.05 0.03 0.08SL99-04 8 9.5 1.5 0.3 0.03 0.02 0.05SL99-04 48.6 51.5 2.9 0.71 0.1 0.06 0.16SL99-05 13.5 21 7.5 0.58 0.33 0.14 0.47including 14 17.5 3.5 0.71 0.43 0.18 0.61SL99-05 22.65 25.95 3.3 0.41 0.18 0.08 0.26SL99-06 36.95 37.15 0.2 0.45 0.14 0.11 0.25SL99-06 44.3 55.25 10.95 0.74 0.47 0.21 0.68including 45 53 8 0.88 0.61 0.26 0.87SL99-06 56 58.47 2.47 0.27 0.02 0.06 0.08
Table 5-22. Summary of drill core assay results from diamond drilling by Pacific North
West Capital Corp. (1999) at the Sargesson Lake occurrence in the Sargesson Lake
intrusion, Janes Township. Results are from (Meyer et al., 2000). Values for 3E =
Pt+Pd+Au.
280
Sample JB97-109 is a medium-grained orthopyroxene gabbro containing ~15% visible
sulphide (chalcopyrite, pyrrhotite, pentlandite), collected from the northern part of the
mineralized trend (Trench 4) at the Rastall occurrence (Fig. 5-73; Photo 5-7).
All of the samples plot with much lower TiO2 concentrations than average chilled
margin gabbro and the sample of chilled margin gabbro (JB98-224) from the Chiniguchi
River intrusion, and the vast majority of samples have higher MgO concentrations than
average chilled margin gabbro (Fig. 5-75). This same characteristic is recorded in other
intrusions in this study (i.e. Charlton Lake, Bell Lake, and Kukagami Lake intrusions)
and as in the other intrusions this feature is attributed to the presence of orthopyroxene
phenocrysts in much of the gabbro that makes up the Chiniguchi River intrusion.
5.12.3 Trace and Rare-Earth Element Variations
Ratios of (La/Sm)N and (Th/Nb)N show little evidence for local crustal contamination
in either the mineralized (>0.05 wt% S) or unmineralized (<0.05 wt% S) rocks and
moreover, the ratios are tightly constrained, ranging ~4-8 (Th/Nb)N and ~1.8-2.2
(La/Sm)N, which suggests a major contamination event in a deeper seated magma
(staging) chamber. As with many of the mineralized Nipissing Gabbro intrusions in this
study (Fig. 5-13), the Pd concentrations from these samples show no correlation with
either of these ratios, indicating that the sulphide mineralizing event was independent of
this major contamination event. The values of the two samples that fall outside of these
ranges are the result of local contamination. For example, sample JB97-109 (5.3 wt% S,
1300 ppb Pt, 4560 ppb Pd, 17080 ppm Cu, 10560 ppm Ni) which has very high ratios, is
extensively altered and was collected from Trench 4 at the Rastall occurrence (Fig. 5-73),
within ~1-2 m from the contact with sedimentary country rock, and proximal to a
sediment-gabbro breccia.
Primitive mantle-normalized multi-element diagrams for samples from the
Chiniguchi River intrusion are shown in Figure 5-76; one sample (JB97-115) is from the
Sargesson Lake intrusion (Fig. 5-72). With the exception of the patterns exhibited by the
LILE, the patterns from all of the rocks are near-parallel and typical of Nipissing Gabbro
with relatively elevated LILE (~1-50 times primitive mantle) and negative Nb+Ta, P*
and T* anomalies; variations in the LILE are likely the result of alteration and subtle re-
mobilization of these elements.
281
Photo 5-7. Chiniguchi River Intrusion, Rastall occurrence (Trench 4). (A) Gossan from semi-massive to massive sulphide mineralization proximal to the contact (shown as dashed line) with sedimentary rocks. At this exposure, the gabbro forms a tongue-like body into the surrounding sediments. The surface exposure is about 6 m wide. (B) Malachite-stained (malachite) sulphide mineralization at the sheared and brecciated (sediment-gabbro breccia) contact with fine-grained (chilled) gabbro. The Canadian one dollar coin is about 2.5 cm in diameter.
282
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
4567891011
MgO (wt%)
TiO
2 (w
t%)
JB98-224JB97-40AJB97-40BJB97-41AJB97-41BJB97-41CJB97-42AJB97-42BJB97-67JB97-106AJB97-106CJB97-43AJB97-43BJB97-43CJB97-43DJB97-95JB97-106BJB97-107JB97-108JB97-109JB97-104JB97-105JB97-87AJB97-87BJB97-87CJB97-87DJB97-87EJB97-87FJB97-87GJB97-87HJB97-87IJB97-87JJB97-87KJB97-115Chilled Margin Avg
fractionation
(B) B A ) gabbro (CIPW)+ leucogabbro (CIPW)D chilled margin gabbro (CIPW gabbro)
Figure 5-75. Bivariate scatter plot of MgO versus TiO2 for rock samples from the
Chiniguchi River and Sargesson Lake (JB97-115) intrusions. Average chilled margin
gabbro is from this study.
283
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB98-224
Chilled Margin Avg
D chilled margin gabbro (CIPW gabbro)
(A) CHILLED MARGIN GABBRO
0.1
1
10
100
1000
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti* Tb Y Tm Yb
Sam
ple/
Prim
itive
Man
tle
JB97-41AJB97-43AJB97-43CJB97-95JB97-96JB97-109JB97-87CChilled Margin Avg
B A ) gabbro (CIPW)+ leucogabbro (CIPW)
(B) ATYPICAL SAMPLE PROFILES
Figure 5-76. Primitive mantle-normalized multi-element diagrams for rock samples from the Chiniguchi River and Sargesson Lake (JB97-115) intrusions, Janes Township. Mantle normalizing values are from McDonough and Sun (1995).
284
5.12.4 Chalcophile (PGE, Cu, Ni) Element Variations
Mineralized samples (>500 ppm Cu and >0.1 wt% S) were collected from 4 areas;
15 samples from the Rastall occurrence, one sample from the Sargesson Lake occurrence,
one sample from the KTO showing, and 4 samples from the NKTO showing (Fig. 5-72).
The sulphides are primarily disseminated and bleb textured, ranging from 1-5 volume %,
and dominated by chalcopyrite and pyrrhotite with subordinate pentlandite and rare
pyrite. The highest concentrations of PGE, collected from Trench 1 at the Rastall
occurrence (Fig. 5-73), are from samples JB97-43A (~8023 ppb Pt+Pd; ~9.0 Pd/Pt; ~2.4
Cu/Ni), JB97-96 (~7481 ppb Pt+Pd; ~20.7 Pd/Pt; ~2.7 Cu/Ni), and JB97-109 (~5860
Pt+Pd; ~3.5 Pd/Pt; ~1.6 Cu/Ni); a series of 7 samples, also collected from Trench 1, have
concentrations ranging from 1065 ppb Pt+Pd to 3867 ppb Pt+Pd (average ~5.9 Pd/Pt,
~2.4 Cu/Ni). Metal ratios in the mineralized (>0.05 wt% S) samples average 6.6 Pd/Pt
and 2.3 Cu/Ni with a median of 4.7 Pd/Pt and 3.2 Cu/Ni, and unmineralized (<0.05 wt%
S) samples average 1.8 Pd/Pt and 0.8 Cu/Ni with a median of 1.9 Pd/Pt and 0.7 Cu/Ni.
These high Pd/Pt and Cu/Ni ratios are indicative of fractionated sulphides.
There is strong correlation between concentrations of Cu-Pt and Cu-Pd (Fig. 5-77),
as well as S-Pt and S-Pd, indicating that the PGE are largely sulphide controlled. The
bivariate plots in Figure 5-77 also exhibit two distinct groups. Group-1 consists of
unmineralized and mineralized samples from the Rastall and Sargesson Lake
occurrences, includes the sample of chilled gabbro and average chilled margin gabbro,
and has higher concentrations of Pt and Pd relative to Group-2. Group-2 consists solely
of mineralized samples (>0.05 wt% S) collected from the KTO and NKTO showings
(Fig. 5-73).
With the exception of two unmineralized samples, the whole-rock S/Se
concentrations of the rocks lie within the field of uncontaminated magmatic sulphides
(Naldrett, 1981), between 1000 and 5000 S/Se; the two samples (JB97-106C and JB97-
108) that have <1000 S/Se have probably suffered some loss of S through weathering
(Fig. 5-78a). Figure 5-78b is a plot of Se versus Pd, useful for discriminating between
rocks that formed from S-undersaturated (second-stage or fertile) versus S-saturated
(first-stage or infertile) magmas such as MORB (Peck et al., 2001).
285
1
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100
1000
10000
10 100 1000 10000 100000
Cu (ppm)
Pt (p
pb)
JB98-224 Chill
<0.05wt% S
>0.05wt% S
Chilled Margin Avg
Group-1
Group-2
(A)
1
10
100
1000
10000
10 100 1000 10000 100000
Cu (ppm)
Pd (p
pb)
JB98-224 Chill
<0.05wt% S
>0.05wt% S
Chilled Margin Avg
Group-1
Group-2
(B)
Figure 5-77. Scatter plots of whole-rock chalcophile elements for rock samples from the Chiniguchi River and Sargesson Lake intrusions. (A) Variations in Cu and Pt. (B) Variations in Cu and Pd.
286
1
10
100
1000
10000
100 1000 10000
S/Se
Pd (p
pb)
JB98-224 Chill<0.05wt% S>0.05wt% SChilled Margin AvgHuronian Sediment Avg
sulphur loss magmaticcontamination
+R-factor
JB97-115
JB97-108
JB97-106C
(A)
Figure 5-78a. Discrimination diagram of S/Se versus Pd plotting unmineralized (<0.05
wt% S), mineralized (>0.05 wt% S) and chilled gabbro samples from the Chiniguchi
River and Sargesson Lake intrusions, Janes Township. Samples with S/Se ratios that
range 1,000 to 5,000 are within the range of uncontaminated magmatic sulphides
(Naldrett, 1981) and samples with S/Se <1,000 are attributed to sulphur loss through
weathering or other secondary processes (Reeves and Keays, 1995). Value for average
chilled margin gabbro is from the current study.
287
0.1
1
10
100
1000
10000
0.1 1 10 100 1000 10000 100000
Se (ppb)
Pd (p
pb)
JB98-224 Chill<0.05wt% S>0.05wt% SChilled Margin AvgHuronian Sediment AvgMORB Avg
First-Stage Magmas (MORB)
Second-Stage Magmas (Fertile)
Average MORB
41C
41A
42A40A
41B
40B
42B
(B)
Figure 5-78b. Discrimination diagram of Se versus Pd plotting unmineralized (<0.05
wt% S), mineralized (>0.05 wt% S) and chilled gabbro samples from the Chiniguchi
River and Sargesson Lake intrusions, Janes Township. Value for average chilled margin
gabbro is from the current study. Value for average MORB is from Hamlyn and Keays
(1986).
288
All of the unmineralized samples, along with the chilled gabbro and average chilled
gabbro, plot within the field of second-stage magmas, implying that the source magmas
were PGE metal-fertile magmas which had not previously undergone sulphide
segregation. Seven of the samples, all collected from either the KTO or NKTO sample
sites (Fig. 5-72), plot within the field of first-stage or S-saturated magmas. These
sulphides are extremely enriched in base metal concentrations relative to PGE (~71,338
to 536,692 Cu/Pd) and have clearly precipitated from a magma that has already
experienced sulphide segregation. This suggests that this region of the Chiniguchi River
intrusion has either been fed by a S-saturated magma that was severely deleted in PGE or
that there are PGE-rich sulphide elsewhere in the intrusion.
The majority of samples, and in particular all of the unmineralized (<0.05 wt% S)
samples, have Cu/Pd values of <6500; mineralized samples (>0.05 wt% S) and chilled
gabbro have >6500 Cu/Pd values. Hoatson and Keays (1989) suggested that rocks with
Cu/Pd values >6500 have undergone earlier sulphide segregation and would therefore
contain relatively depleted concentrations of Pd. Within the current sample suite, Pd
concentrations are clearly anomalous and perhaps more significantly, unmineralized
samples have Cu/Pd values that are <6500. Assuming that chilled gabbro represents the
composition of a particular parent magma, then it follows that the rocks sampled from
within the intrusion did not form directly from this same magma. Moreover, although
these magmas are likely related, they clearly represent two differing magma
compositions, either as a result of their petrogenesis, their bulk (source) composition, or
both.
Figure 5-79, a discrimination plot of Ni/Cu versus Pd/Ir is useful to determine
whether or not sulphides are magmatic or hydrothermal in origin, with increasing Pd/Ir
and decreasing Ni/Cu values trending towards a hydrothermal origin. The majority of
samples plot within the region of layered intrusions as described by Barnes (1990), and
these sulphides are interpreted to be magmatic. In contrast, 4 of the mineralized samples,
containing some of the highest concentrations of Pt+Pd, plot near or within the field of
hydrothermal mineralization (Barnes, 1990), suggesting remobilized sulphide.
289
0.01
0.1
1
10
100
1000
10000
100000
0.01 0.1 1 10 100 1000
Ni/Cu
Pd/Ir
JB98-224 Chill<0.05wt% S>0.05wt% SChilled Margin AvgHuronian Sediment Avg
hydrothermal
increased fractionation
mantle
+chromite+olivine
JB97-115
96
43A
43C
109
layered intrusions
Figure 5-79. Discrimination diagram of Ni/Cu versus Pd/Ir of mineralized (>0.05 wt%
S), unmineralized (<0.05 wt% S), and chilled margin gabbro samples from the
Chiniguchi River and Sargesson Lake intrusions, Janes Township. The fields of mantle,
layered intrusions and hydrothermal are approximated from Barnes (1990).
290
Primitive mantle-normalized PGE and chalcophile diagrams (recalculated to metal in
100% sulphide) for 15 mineralized and unmineralized samples that have complete or
near-complete PGE data are shown in Figures 5-80 and 5-81; concentrations of PGE that
are below the lower limit of detection, which are more commonly Ir, Ru and Rh, are
assigned the average value of the lower limit of detection (i.e. Ir = 0.27 ppb; Ru = 0.66
ppb; Rh = 0.26 ppb; Pt = 1.43 ppb; Pd = 1.88 ppb). All of the sulphides are characterized
by positive slopes that approximate those profiles of average chilled margin gabbro and
average flood basalt (Naldrett, 1981) and define two distinct sets of profiles. Group-1
comprises unmineralized (<0.05 wt% S) samples and the sample of chilled gabbro (0.059
wt% S), and Group-2 samples comprise mineralized (>0.05 wt% S) samples (Fig. 5-81).
Group-1 samples have higher overall PGE abundances and slightly shallower positive
slopes, relative to Group-2 samples. Conversely, Group-2 samples have steeper positive
slopes and lower PGE abundances, particularly in Ir, Ru and Rh, relative to Group-1 and
are therefore less fractionated than Group-1 sulphides. Three samples (JB97-43A, 96 and
109), which have some of the highest concentrations of Pt+Pd, plot with much different
profiles in comparison to groups 1 and 2 (Fig. 5-80). These samples, which also plot
within or near the field of hydrothermal sulphides on the Ni/Cu versus Pd/Ir diagram
(Fig. 5-79), have patterns that are similar to those of hydrothermal sulphide
mineralization from the East Bull Lake intrusion (Peck et al., 1993a, 1993b) and from the
South Roby Zone, Lac des Iles Complex (J. Hinchey, unpublished data, 2004).
Indications of hydrothermal mineralization, combined with the magmatic S/Se
values and other indications that these sulphides are magmatic, suggest that a number of
the samples from this sample suite have suffered a hydrothermal overprint. This
interpretation is supported by the mineralogy of the Cu-sulphides which tend to be locally
recrystallized along micro-structures and veinlets as observed in hand samples and thin
sections (Appendix 2).
291
0.1
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10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-224JB97-40BJB97-41BJB97-42BJB97-106CJB97-43AJB97-43CJB97-43DJB97-96JB97-106BJB97-107JB97-108JB97-109JB97-105JB97-115Chilled Margin AvgFlood Basalt Avg
A gabbro (CIPW)+ leucogabbro (CIPW)D chilled margin gabbro (CIPW gabbro)
(A)
Figure 5-80a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from all rock samples,
Chiniguchi River and Sargesson Lake intrusions, Janes Township. Data for average
chilled margin is from this study and data for average flood basalt is from Naldrett
(1981). Mantle normalizing values are from Barnes et al. (1988) and McDonough and
Sun (1995).
292
0.1
1
10
100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB97-43A
JB97-96
JB97-109
Chilled Margin Avg
Flood Basalt Avg
Lac des Iles SRZ Avg
EBL Hydrothermal Avg
A gabbro (CIPW)+ leucogabbro (CIPW)
(B)
Figure 5-80b. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides with atypical patterns, Chiniguchi
River and Sargesson Lake intrusions, Janes Township. Data for average chilled margin
are from this study; data for average flood basalt is from Naldrett (1981); data for
average Lac des Iles – South Roby Zone (SRZ) is from J. Hinchey (unpublished data,
2004); data for average East Bull Lake intrusion hydrothermal sulphide is from Peck et
al. (1993b). Mantle normalizing values are from Barnes et al. (1988) and McDonough
and Sun (1995).
293
0.1
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100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB98-224JB97-106CJB97-106BJB97-107JB97-108JB97-105Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
A gabbro (CIPW)D chilled margin gabbro (CIPW gabbro)
(A) GROUP-1
Figure 5-81a. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from Group-1 samples,
Chiniguchi River intrusion, Janes Township. Data for average chilled margin is from this
study; data for average flood basalt is from Naldrett (1981); data for average East Bull
Lake intrusion hydrothermal sulphide is from Peck et al. (1993b). Mantle normalizing
values are from Barnes et al. (1988) and McDonough and Sun (1995).
294
0.1
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100
1000
10000
100000
1000000
10000000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
JB97-40BJB97-41BJB97-42BJB97-43CJB97-43DJB97-115Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
A gabbro (CIPW)
(B)GROUP-2
Figure 5-81b. Primitive mantle-normalized PGE-chalcophile element diagrams
(recalculated to metals in 100% sulphide) for sulphides from Group-2 samples,
Chiniguchi River and Sargesson Lake intrusions, Janes Township. Data for average
chilled margin is from this study; data for average flood basalt is from Naldrett (1981);
data for average East Bull Lake intrusion hydrothermal sulphide is from Peck et al.
(1993b). Mantle normalizing values are from Barnes et al. (1988) and McDonough and
Sun (1995).
295
5.13 Rastall Occurrence - Drill Holes JR99-01 and 06
In 1999, Pacific North West Capital Corp. completed a diamond drilling program at
the Rastall occurrence (Figs. 5-1 and 5-72) in Janes Township (Jobin-Bevans et al., 1999;
Meyer et al., 2000, 2001). A portion of the drilling program was targeted at semi-
massive to massive sulphide mineralization intersected at the Rastall occurrence by
Kennco Explorations Inc. (ca. 1968), which reported 1.59% Cu and 1.27% Ni over 10.7
m. This same drill core was re-examined by Falconbridge Ltd. in the late 1980s and was
shown to contain 1.86% Cu, 1.51% Ni, 1780 ppb Pt-Pd-Au over 7.9 m.
Core from two of the diamond drill holes, JR99-01 and JR99-06, was examined as
part of the current study (Fig. 5-73). Diamond drill hole JR99-01 (300 Az, -46
inclination, grid BL0+00/0+29E) is located about 31 m north and 20 m east of JR99-06
(300 Az, -45 inclination, grid L0+31S/0+09E). These 2 drill holes, along with a third
(JR99-11), define a southeast-dipping (25-35°) layer of Cu-Ni-PGE sulphide-bearing
orthopyroxene gabbro with a true width of about 14.0 m and extending a minimum of 60
m down-dip from surface mineralization in Trench 1 (Fig. 5-74). On the basis of field
observations, the increase in the ratio of felsic to mafic minerals in rock samples from
west to east and the increase in the ratio of felsic mafic minerals in core samples upward
through the hole, the western contact is interpreted to be the basal contact of the
intrusion. A total of 23 samples, including a sample of footwall sedimentary rock, were
selected for whole-rock major element, PGE, Au, S, Se, Cu and Ni analyses, comprising
8 samples from drill hole JR99-01 and 15 samples from drill hole JR99-06. These data
were combined into a composite drill hole section (Table 5-23; Fig. 5-74). For the
purposes of plotting, a value of one half of the lower limit of detection is used where
elements have concentrations that are below the lower limits of detection (i.e. Ir = 0.025
ppb; Ru = 0.125 ppb; Rh = 0.125 ppb; Pt = 0.5 ppb; Pd = 0.5 ppb; Au = 0.5 ppb). A
complete listing of the data, along with drill core logs, are provided in Appendix 3.
5.13.1 Major Element Variations
The 22 core samples of intrusive rocks from the composite drill hole section are
characterized by 48.3 wt% SiO2, 0.42 wt% TiO2, 14.0 wt% Al2O3, 9.1 wt% MgO, and
Mg-number of 67. The main mineralized zone, consisting of 9 core samples from 12.54
m to 23.09 m, is characterized by 47.8 wt% SiO2, 0.42 wt% TiO2, 13.9 wt% Al2O3, 8.5
296
wt% MgO, and Mg-number of 63. All of the samples CIPW normative calculations,
completed on the 22 samples (Table 5-19), classify 17 samples as quartz-hypersthene-
normative (silica-oversaturated) gabbro, 4 samples as hypersthene-olivine-normative
(silica-saturated) gabbronorite (~1.4-7.0 wt% normative olivine), and 1 sample as
hypersthene-olivine-normative olivine leucogabbronorite (~27 wt% normative olivine).
In the field, core samples described as vari-textured gabbro classify as CIPW gabbro
and gabbronorite, orthopyroxene gabbro classify mainly as gabbro and subordinate
gabbronorite, and gabbro classify as gabbro and olivine leucogabbronorite. Except for
sample 44725, a medium-grained massive gabbro (CIPW olivine leucogabbronorite)
which plots in the field of alkaline rocks.
In comparison to average chilled margin gabbro, all of the samples plot with lower
TiO2 compositions and higher MgO concentrations and most of the samples have higher
Mg-numbers (Fig. 5-82). Specifically, gabbroic rocks from the upper portion of the drill
hole have lower TiO2 and generally higher Mg-numbers and MgO concentrations relative
to the gabbroic rocks from the lower portion of the drill hole; rocks from the main
mineralized zone have the lowest Mg-numbers and MgO concentrations. The higher
MgO and lower TiO2 compositions, relative to average chilled margin gabbro, can be
attributed to the presence of orthopyroxene phenocrysts (hypersthene) in most of the core
samples.
Variations in selected major elements are plotted against diamond drill hole depth
(stratigraphic height) in Figures 5-83 and Figure 5-84. Concentrations of SiO2, although
variable in the lowermost samples, display a general increase upward through the drill
hole. Within the main mineralized zone, SiO2 concentrations are generally lower relative
to the underlying gabbro samples, followed by a sharp decrease in SiO2 immediately
above the main mineralized zone, followed by a gradual upward increase (Fig. 5-83).
Concentrations in TiO2 exhibit a gradual upward decline through the drill section (Fig. 5-
83). The highest concentrations are in the lowermost gabbros which may attributed to
contamination from footwall sedimentary rocks.
297
Sample Drill Hole Description CIPW From To Interval CompositeNorm wt% (m) (m) (m) Depth (m)
44731 JR99-01 mg; vt gabbro GN (H-O) 2.50 2.95 0.45 1.0044737 JR99-01 fg-mg; vt gabbro G (Q-H) 5.54 6.16 0.62 4.2144744 JR99-01 mg; opx-gabbro GN (H-O) 9.41 10.41 1.00 8.4644769 JR99-01 mg; opx-gabbro GN (H-O) 14.00 14.45 0.45 12.5044792 JR99-01 mg; opx-gabbro GN (H-O) 17.43 17.95 0.52 16.0044799 JR99-01 mg; opx-gabbro G (Q-H) 20.50 21.25 0.75 19.3044805 JR99-01 mg; opx-gabbro G (Q-H) 24.46 25.07 0.61 23.1244812 JR99-01 mg; opx-gabbro G (Q-H) 29.28 30.15 0.87 28.2044685 JR99-06 mg; opx-gabbro G (Q-H) 10.15 10.45 0.30 33.2044692 JR99-06 mg; opx-gabbro G (Q-H) 12.54 12.75 0.21 35.5044700 JR99-06 mg; opx-gabbro G (Q-H) 15.64 15.98 0.34 38.7344705 JR99-06 mg; opx-gabbro G (Q-H) 17.84 18.27 0.43 41.0244708 JR99-06 mg; opx-gabbro G (Q-H) 19.13 19.50 0.37 42.2544711 JR99-06 mg; opx-gabbro G (Q-H) 20.09 20.45 0.36 43.2044713 JR99-06 mg; opx-gabbro G (Q-H) 20.86 21.33 0.47 44.0844714 JR99-06 mg; opx-gabbro G (Q-H) 21.33 21.87 0.54 44.6244716 JR99-06 mg; opx-gabbro G (Q-H) 22.16 22.41 0.25 45.1644718 JR99-06 mg; opx-gabbro G (Q-H) 22.64 23.09 0.45 45.8444720 JR99-06 mg; opx-gabbro G (Q-H) 23.52 23.91 0.39 46.6644722 JR99-06 mg; gabbro G (Q-H) 24.25 24.75 0.50 47.5044725 JR99-06 mg; gabbro OLGN (H-O) 25.50 25.68 0.18 48.4344758 JR99-06 mg; gabbro G (Q-H) 28.49 29.00 0.51 51.7544861 JR99-06 sediment sediment 44.38 45.74 1.36 68.49
Table 5-23. Summary of drill hole data for the composite drill hole, comprising drill
holes JR99-01 and JR99-06, from the Rastall property, Chiniguchi River intrusion, Janes
Township. "-" below lower limit of detection; "N" = primitive mantle-normalized;
"na"=not analyzed; fg=fine-grained; mg=medium-grained; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; opx=orthopyroxene; vt=vari-
textured; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-
hypersthene-corundum. Norm wt% = rock types determined on the basis of weight
percent normative minerals calculated to normative weight percent.
298
Sample Composite Pt Pd Cu Ni S Se Mg#Depth (m) ppb ppb wt% wt% wt% ppb
44731 1.00 15.30 40.00 63 43 0.03 192 7444737 4.21 19.00 68.10 106 60 0.05 280 7544744 8.46 28.00 141.60 193 104 0.09 421 7444769 12.50 38.20 81.90 1635 654 0.50 2564 7444792 16.00 62.50 123.50 2991 1206 0.80 4770 7244799 19.30 42.80 46.70 1759 782 0.44 2614 7244805 23.12 94.30 181.00 4578 1948 1.34 6878 6844812 28.20 92.60 313.00 4489 1625 1.33 6150 6744685 33.20 268.00 858.00 8793 4642 3.23 16912 6144692 35.50 353.00 1540.00 11788 3640 2.82 14415 6244700 38.73 311.00 1617.00 6769 2510 1.69 8242 6544705 41.02 378.00 2009.00 7851 2914 1.92 10290 6344708 42.25 395.00 2119.00 7306 2712 1.84 8235 6344711 43.20 554.00 2677.00 8604 4719 2.65 10718 6144713 44.08 549.00 2482.00 9147 4539 2.61 9990 6144714 44.62 548.00 2118.00 10182 4827 2.83 13462 6044716 45.16 310.00 1603.00 5410 2964 1.75 7320 6544718 45.84 356.00 1624.00 6195 2914 1.83 7545 6444720 46.66 152.00 851.00 2633 1202 0.59 2985 6844722 47.50 13.30 33.40 154 107 0.06 244 6944725 48.43 10.50 19.30 42 101 0.22 155 7644758 51.75 9.90 11.95 76 68 0.06 222 6944861 68.49 1.37 2.84 18 91 0.02 32 77
Table 5-23 (cont). Summary of drill hole data for the composite drill hole, comprising
drill holes JR99-01 and JR99-06, from the Rastall property, Chiniguchi River intrusion,
Janes Township. "-" below lower limit of detection; "N" = primitive mantle-normalized;
"na"=not analyzed; fg=fine-grained; mg=medium-grained; G=gabbro; OLGN=olivine
leucogabbronorite; LG=leucogabbro; GN=gabbronorite; opx=orthopyroxene; vt=vari-
textured; Q-H=quartz-hypersthene; H-O=hypersthene-olivine; Q-H-C=quartz-
hypersthene-corundum.
299
0.30
0.35
0.40
0.45
0.50
0.55
0.60
0.65
0.70
0.75
50556065707580
Mg-number
TiO
2 (w
t%)
4473144737447444476944792447994480544812446854469244700447054470844711447134471444716447184472044722447254475844861Chilled Margin Avg
fractionation
Mineralized Zone
Lower Gabbros
Upper Gabbros
A g gabbro (CIPW)) gabbronorite (CIPW)# olivine leucogabbronorite (CIPW)+ sediment
(A)
0.30
0.35
0.40
0.45
0.50
0.55
0.60
0.65
0.70
0.75
4567891011121314
MgO (wt%)
TiO
2 (w
t%)
4473144737447444476944792447994480544812446854469244700447054470844711447134471444716447184472044722447254475844861Chilled Margin Avg
fractionation
A g gabbro (CIPW)) gabbronorite (CIPW)# olivine leucogabbronorite (CIPW)+ sediment
(B)
Figure 5-82. Bivariate scatter plots of core samples from the composite drill hole from the Rastall property, Chiniguchi River intrusion. (A) Variations in Mg-number and TiO2. (B) Variations in MgO and TiO2. Average chilled margin gabbro is from this study.
300
0
10
20
30
40
50
60
7040 42 44 46 48 50 52 54 56
SiO2 (wt%)
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
(A)
main mineralized zone
Figure 5-83a. Profile through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, showing stratigraphic variations in SiO2.
301
0
10
20
30
40
50
60
700.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7
TiO2 (wt%)
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
(B)
main mineralized zone
Figure 5-83b. Profile through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, showing stratigraphic variations in TiO2.
302
0
10
20
30
40
50
60
7050 55 60 65 70 75 80
Mg-number
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
(A)
main mineralized zone
Figure 5-84a. Profile through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, showing stratigraphic variations in Mg-number.
303
0
10
20
30
40
50
60
706 7 8 9 10 11 12 13 14
MgO (wt%)
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
(B)
main mineralized zone
Figure 5-84b. Profile through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, showing stratigraphic variations in MgO.
304
Within the main mineralized zone, TiO2 shows a sharp decline relative to the underlying
gabbros, followed by a gradual decline upward through the remainder of the drill section.
As illustrated in the diagrams of Mg-number and MgO versus TiO2 (Fig. 5-82b),
concentrations of MgO and Mg-numbers are highest in the rocks that underlie the main
mineralized zone, and display a gradual upward increase through the overlying gabbros,
followed by a decrease through the uppermost vari-textured gabbro (Fig. 5-84).
5.13.2 Chalcophile (PGE, Cu, Ni) Elements
Stratabound sulphide mineralization consisting of ~3-5% disseminated sulphide, was
intersected in drill holes JR99-01 and JR99-06, where it is hosted by massive to locally
fractured orthopyroxene gabbro (Fig. 5-83). In the composite drill section, this main
mineralized zone is represented by the interval from 35.50 m to 45.84 m as summarized
in Table 5-23. The main mineralized zone averages 2394 ppb Pt+Pd, 8139 ppm Cu and
3527 ppm Ni (4.7 Pd/Pt; 2.3 Cu/Ni), contrasting the concentrations in 2 unmineralized
(<0.05 wt% S) samples which average 71 ppb Pt+Pd, 84.5 ppm Cu and 51.5 ppm Ni (3.1
Pd/Pt; 1.6 Cu/Ni). The highest individual PGE concentration is from sample 44711
which contains 554 ppb Pt, 2677 ppb Pd, 405 ppb Au, 8604 ppm Cu and 4719 ppm Ni
(4.8 Pd/Pt; 1.8 Cu/Ni).
Selected bivariate plots of chalcophile element concentrations for the drill core
samples are provided in Figure 5-85. Correlations between the chalcophile elements Pt-
Cu and Pd-Cu are very good, indicating that the PGE are strongly sulphide controlled.
All of the samples except 44725, a CIPW olivine leucogabbronorite from the lower part
of the drill hole section, have S/Se values between 1000 and 5000 and plot within the
field of uncontaminated magmatic sulphide (Fig. 5-86a). Sample 44725, which has a
contamination signature suggesting addition of external S, is located within about 20 m of
the footwall sedimentary rocks. In the discrimination diagram of S/Se versus Pd, all of
the samples, and in particular the unmineralized samples, plot within the field of second-
stage, PGE-fertile, magmas (Fig. 5-86b), as described by Peck et al. (2001) and Hamlyn
et al. (1985). All of the samples, except 44725, have restricted MgO compositions (~8.1-
10.1 wt% MgO) with the samples from the main mineralized zone having the highest Ir
concentrations, reflecting the primitive nature of these rocks and their higher PGE
abundances.
305
1
10
100
1000
10000
100000
1 10 100 1000 10000
Pt (ppb)
Cu
(ppm
)
<0.05wt% S
>0.05wt% S
Main Mineralized Zone
Chilled Margin Avg
(A)
1
10
100
1000
10000
100000
1 10 100 1000 10000
Pd (ppb)
Cu
(ppm
)
<0.05wt% S
>0.05wt% S
Main Mineralized Zone
Chilled Margin Avg
(B)
Figure 5-85. Bivariate scatter plots of whole-rock chalcophile elements for core samples from the Rastall property, Chiniguchi River intrusion, sorted by mineralized (>0.05 wt% S), unmineralized (<0.05 wt% S), and chilled gabbro (JB98-224). (A) Variations in Pt and Cu. (B) Variations in Pd and Cu. Average chilled margin gabbro is from this study.
306
1
10
100
1000
10000
100 1000 10000 100000
S/Se
Pd (p
pb)
<0.05wt% S
>0.05wt% S
Main Mineralized Zone
Chilled Margin Avg
sulphur loss magmatic contamination
+R-factor
44725 (OLGN)
(A)
Figure 5-86a. Discrimination diagram of S/Se versus Pd plotting unmineralized (<0.05
wt% S), mineralized (>0.05 wt% S), and chilled gabbro samples from the Rastall
property, Chiniguchi River intrusion. Samples with S/Se ratios that range 1,000 to 5,000
are within the range of uncontaminated magmatic sulphides (Naldrett, 1981) and samples
with S/Se <1,000 are attributed to sulphur loss through weathering or other secondary
processes (Reeves and Keays, 1995).
307
0.1
1
10
100
1000
10000
0.1 1 10 100 1000 10000 100000
Se (ppb)
Pd (p
pb)
<0.05wt% S>0.05wt% SMain Mineralized ZoneChilled Margin AvgMORB Avg
First-Stage Magmas (MORB)
Second-Stage Magmas (Fertile)
Average MORB
(B)
Figure 5-86b. Discrimination diagram of Se versus Pd plotting unmineralized (<0.05
wt% S), mineralized (>0.05 wt% S) and chilled gabbro samples from the Rastall
property, Chiniguchi River intrusion. Value for average chilled margin gabbro is from
the current study. Value for average MORB is from Hamlyn and Keays (1986).
308
0
10
20
30
40
50
60
700.01 0.1 1 10 100 1000 10000 100000
Concentration and Ratio
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
Cu/Pd
Pt (ppb) Pd (ppb)Pd/SePt/Se
main mineralized zone
S (ppm)
Cu (ppm)
Ni (ppm)
(A)
Figure 5-87a. Profiles through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, Janes Township, showing stratigraphic variations in Pt/Se,
Pd/Se, Pt, Pd, Cu, Ni, S and Cu/Pd.
309
0
10
20
30
40
50
60
700.1 1 10 100 1000 10000 100000
Concentration and Ratio
Dril
l Hol
e D
epth
(m)
sediment
gabbro (OLGN)gabbro (G)
gabbro (G)
orthopyroxene gabbro (G)
orthopyroxene gabbro (GN)
vt gabbro (G)
vt gabbro (GN)
S/SePd/PtCu/Ni
main mineralized zone
Se (ppb)
(B)
Figure 5-87b. Profiles through the composite drill hole from the Rastall property,
Chiniguchi River intrusion, Janes Township, showing stratigraphic variations in Cu/Ni,
Pd/Pt, Se and S/Se.
310
The Ni/Cu and Pd/Ir ratios from these samples are within the range of layered intrusions
with some sulphides (main mineralized zone) having elevated Pd/Ir values, suggesting
that some of the samples have suffered hydrothermal overprint.
Data for selected chalcophile elements and ratios are plotted against drill hole depth
in Figure 5-87. Moving upward in stratigraphy, the transition from non-mineralized
gabbro (lower fine- to medium-grained gabbro) to mineralized gabbro (orthopyroxene-
bearing gabbro) is gradational. In contrast the base of the mineralized zone is marked by
a rapid increase in Pt-Pd and Cu-Ni values over several centimetres. In general,
concentrations of Pt, Pd, Cu, Ni and S, including their maxima, are positively correlated
and the remarkably uniform concentrations through the main mineralized zone testify to
their magmatic origin. Subsequent to peaking within the lower part of the main
mineralized zone, Pt, Pd, Cu, Ni and S exhibit a systematic and gradual decline upward
through the section. The relationship between ratios of Pt/Se and Pd/Se and whole-rock
abundances of Pt, Pd and Se are shown plotted against drill hole depth in Fig. 5-87. The
maxima of Pt, Pd and Se are positively correlated, occurring within the lower part of the
main mineralized zone. However, the maxima for Pt/Se and Pd/Se ratios are offset from
this maxima, with the Pt/Se peak occurring below the main mineralized zone, in the
CIPW olivine leucogabbronorite, and the Pd/Se peak occurring immediately prior to the
main mineralized zone; the peak Se concentration is also offset from peak Pt and Pd
concentrations. The overall decline in Pt/Se and Pd/Se is indicative of precipitation of
PGE-bearing sulphides, with the magma becoming progressively depleted in PGE and
relatively enriched in Se (and S) as the sulphides formed; it is probable that sulphide
fractionation would have also been accompanied by sulphide settling. Barnes et al.
(1988) and Hoatson and Keays (1989) demonstrated that in general, Cu/Pd ratios of
<6500 were indicative of magmas that had not experience sulphide segregation. In
Figure 5-87a, Cu/Pd values are <6500 within the lower portion of the drill hole,
increasing through the main mineralized zone, surpassing 6500 near the upper part of the
main mineralized zone, increasing gradually upward through the section, then declining
through the upper part of the orthopyroxene gabbro and into the vari-textured gabbros.
These data suggest that the magma became S-saturated or was nearly S-saturated at the
stratigraphic level immediately underlying the main mineralized zone, becoming fully S-
311
saturated at approximately the 35 m level; similar trends were noted by Reeves and
Keays (1995) in the Bucknalla Complex, Australia. Apart from changes in the total
sulphide content, there are no petrologic breaks between upper and lower mineralized and
non-mineralized rock units. This suggests that the PGE-rich sulphide mineralization in
the main mineralized zone developed through normal fractionation processes, and are
therefore enriched toward the base of the intrusion. However, it is unclear as to whether
the sulphide-rich orthopyroxene gabbro unit is part of a single magma pulse or just one of
several pulses that may have formed the Chiniguchi River intrusion.
Primitive mantle-normalized PGE and chalcophile element diagrams for mineralized
and unmineralized drill core samples shown in Figure 5-88, and are compared to average
chilled margin gabbro (this study), average flood basalt (Naldrett, 1981), average South
Roby Zone from the Lac des Iles Complex (J. Hinchey unpublished data, 2004); and
hydrothermal sulphide mineralization from the East Bull Lake intrusion (Peck et al.,
1993b). All of the samples display positive slopes with elevated Pt, Pd, Au and Cu
relative to Ni, Ir, Ru and Rh and in general follow patterns that are similar to average
chilled margin gabbro and average flood basalt. However, in detail the sulphide patterns
define two groups, distinguished by peaks in the abundance of Pd. Group-1 (Fig. 5-88a),
characterized by Pd peaks that are well above that of average chilled gabbro, comprises
the 3 uppermost samples, all of the samples from the main mineralized zone, and 2
samples that immediately underlie the main mineralized zone. Group-2 (Fig. 5-88b),
characterized by Pd abundances that are lower than Group-1 and lower than average
chilled margin gabbro, comprises 6 samples that immediately overly the main
mineralized zone, and the 2 lowermost gabbroic samples in the section. The majority of
Group-1 and -2 samples display profiles that are similar to that of East Bull Lake
hydrothermal sulphide mineralization but with higher peak Pd abundances in Group-1
and lower Pd abundances in Group-2. The nine core samples from the main mineralized
zone (Fig. 5-88c) have patterns that are similar to the profiles of East Bull Lake
hydrothermal mineralization (Peck, 1993) and remobilized sulphide mineralization from
the South Roby Zone, Lac des Iles Complex (Brügmann et al., 1989), suggesting that
these sulphides have suffered hydrothermal overprint.
312
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
4473144737447444469244700447054470844711447134471444716447184472044722Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
A g gabbro (CIPW)) gabbronorite (CIPW)
(A)
GROUP-1
Figure 5-88a. Group-1 samples. Primitive mantle-normalized PGE-chalcophile element
diagrams (recalculated to metals in 100% sulphide) for sulphides from the composite
drill hole core samples, Rastall property, Chiniguchi River intrusion, Janes Township.
Data for average chilled margin is from this study; data for average flood basalt is from
Naldrett (1981); data for average East Bull Lake intrusion hydrothermal sulphide is from
Peck et al. (1993b). Mantle normalizing values are from Barnes et al. (1988) and
McDonough and Sun (1995).
313
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
4476944792447994480544812446854472544758Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal Avg
(B)
A g gabbro (CIPW)) gabbronorite (CIPW)# olivine leucogabbronorite (CIPW)
GROUP-2
Figure 5-88b. Group-2 samples. Primitive mantle-normalized PGE-chalcophile element
diagrams (recalculated to metals in 100% sulphide) for sulphides from the composite
drill hole core samples, Rastall property, Chiniguchi River intrusion, Janes Township.
Data for average chilled margin is from this study; data for average flood basalt is from
Naldrett (1981); data for average East Bull Lake intrusion hydrothermal sulphide is from
Peck et al. (1993b). Mantle normalizing values are from Barnes et al. (1988) and
McDonough and Sun (1995).
314
1
10
100
1000
10000
100000
Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
100
% S
ulph
ide/
Prim
itive
Man
tle
446924470044705447084471144713447144471644718Chilled Margin AvgFlood Basalt AvgEBL Hydrothermal AvgLac des Iles SRZ Avg
A g gabbro (CIPW)
(C)
Mineralized Zone
Figure 5-88c. Main Mineralized Zone. Primitive mantle-normalized PGE-chalcophile
element diagrams (recalculated to metals in 100% sulphide) for sulphides from the
composite drill hole core samples, Rastall property, Chiniguchi River intrusion, Janes
Data for average chilled margin is from this study; data for average flood basalt is from
Naldrett (1981); data for average Lac des Iles – South Roby Zone (SRZ) is from J.
Hinchey (unpublished data, 2004); data for average East Bull Lake intrusion
hydrothermal sulphide is from Peck et al. (1993b). Mantle normalizing values are from
Barnes et al. (1988) and McDonough and Sun (1995).
315
5.14 Summary
Nipissing Gabbro suite intrusions cover more than 25% of the study area where they
form an extensive system of mafic intrusions. The distribution of these sills, dikes and
possible cone sheets suggest that they represent the intrusive portion of an eroded
continental flood basalt (Lightfoot et al., 1986, 1987; Lightfoot and Naldrett, 1996). The
current study has augmented earlier work by such as authors as Lightfoot and Naldrett
(1996) and Conrod (1988), and presents detailed information specifically regarding the
chalcophile elements in these mafic bodies. On the basis of the geochemical data
presented in the current study, and from previous studies (e.g. Lightfoot and Naldrett,
1996), a number of conclusions can be made regarding the chemistry and petrogenesis of
these intrusions in the context of the sulphide mineralization.
Controls on Mineralization
1) The identification of lower portions of the Nipissing Gabbro intrusions and in
particular the identification of the lowermost Orthopyroxene Gabbro (gabbronorite)
Unit. This unit has been identified as the most prospective to host magmatic
sulphides and would most likely be encountered in the least differentiated intrusions.
2) Base metal (Cu, Ni) concentrations with very low PGE were recorded in rocks from
the upper stratigraphy in intrusions that also host significant PGE-rich magmatic
sulphide near the base of the intrusion (e.g. Chiniguchi River intrusion). This
difference in base-metal to PGE concentrations suggests that PGE-rich sulphide
precipitated through normal in-situ fractionation, from the base upwards, resulting in
a sharp increase in the base-metal to PGE ratio, toward the hangingwall of the
intrusion.
Major Element Chemistry
1) Rocks from Nipissing Gabbro intrusions are for the most part sub-alkaline and
tholeiitic but with more evolved rocks trending toward calc-alkaline compositions.
The majority of samples from this study classify as CIPW silica-oversaturated,
quartz-hypersthene-normative gabbro and leucogabbro; several of the more mafic
samples, referred to as orthopyroxene gabbro, classify as CIPW melagabbronorite,
316
olivine gabbronorite and gabbronorite. However, most of the rocks considered to be
orthopyroxene gabbro classified as CIPW gabbro.
2) Geochemical characteristics of the sample suite include median values of ~51.3 wt%
SiO2 (lowest = 45.9 wt%), 0.52 wt% TiO2 (lowest = 0.4 wt%), 8.4 wt% MgO
(highest = 19.41 wt%) and an Mg-number of 66 (highest = 83). Chilled margin
gabbro, considered to be reflective of parental magma compositions, are
characterized by 49.8-51.9 wt% SiO2 (average = 50.0 wt% SiO2), 0.52-0.89 wt%
TiO2 (average = 0.69 wt% TiO2), 6.13-8.43 wt% MgO (average = 7.73 wt% MgO),
and 52-66 Mg-number (average = 61 Mg number).
3) Wide ranges in the relative concentrations of MgO and TiO2 and with the Mg-
number, suggest that the magmas underwent a considerable amount of in situ
fractionation.
Trace Element Geochemistry
1) Primitive mantle-normalized REE patterns for the majority of Nipissing Gabbro
rocks are characterized by LREE enrichment, narrow ranges in (La/Yb)N, and
chondrite-normalized modest positive and negative Eu anomalies. REE patterns
from mineralized samples are similar to those from unmineralized samples,
suggesting a common origin.
2) Consistently low (La/Sm)N values record a crustal contamination signature and
are similar in mineralized and unmineralized rocks, suggesting that the
contamination signature had nothing to do with the mineralizing event. In
addition, the high (Th/Yb)N values (~2-10 times primitive mantle) are interpreted
to be a consequence of crustal contamination of a mantle-derived magma.
3) The majority of REE patterns exhibit LILE enrichment and negative Nb and Ta
anomalies. In each case, however, the negative Nb anomalies are much larger
than those of Ta. The majority of samples have Nb, Ta, Th values that fit a
mixing curve between N-MORB and continental sediments, with values on that
curve that suggest ~20% crustal contamination of the source magma. Continental
flood basalts or boninitic magmas are good candidates for this chemistry,
exhibiting continental crust signatures.
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4) All of the rock samples from the Nipissing Gabbro intrusions have very low
Nb/Ta and Zr/Sm values relative to MORB, primitive mantle, continental crust
and modern adakites. This is interpreted to mean that Nipissing gabbro magmas
interacted with an extensive crustal reservoir, adopting crustal signatures typical
of rift-related magmas and/or continental flood basalt.
Chalcophile Geochemistry
1) The estimated background PGE-Cu-Ni composition for Nipissing Gabbro
intrusions, which also provides an estimate for the parental magma composition,
is ~4 ppb Au, 12 ppb Pt, 21 ppb Pd, 91 ppm Cu and 149 ppm Ni.
2) Good correlations exist between the chalcophile elements indicating that the
majority PGE are strongly sulphide controlled. Metal ratio diagrams (Ni/Cu-
Pd/Ir, Cu/Ir-Ni/Pd, wt% MgO-Pd/Ir; S/Se; Pd/Ir) also support a magmatic origin.
3) Sulphides in chondrite-normalized PGE diagrams exhibit patterns that are
consistent with a magmatic origin for the sulphides. Sulphides from chilled
gabbro and gabbroic rocks have PGE patterns that are most similar to continental
flood basalt, suggesting a common origin. A few PGE patterns with very low
Pd/Ir values suggest that at least some of the rocks were formed from magmas
that were less fractionated that continental flood basalt.
4) Discrimination plots of Se vs Pd show that the magmas from which the sulphides
precipitated were PGE metal-fertile second-stage magmas (S-undersaturated) that
had not previously segregated sulphides to any large degree.
5) Evidence for PGE depletion in sulphide-bearing rocks that potentially overly
PGE-rich mineralization suggests that the sulphides were dissolved in the magmas
when they entered the chamber and that they precipitated under normal
fractionation within the Nipissing Gabbro chamber
6) The majority of the sulphides from mineralized rocks can be modelled using R
factors that are dominantly <1000.
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CHAPTER 6: RIVER VALLEY INTRUSION
6.1 Introduction
Comprehensive and systematic studies of the East Bull Lake suite intrusions began
with the work of Born (1979), who documented the geology of the East Bull Lake
intrusion. Academic studies and minor base metal exploration, focusing mainly on the
East Bull Lake and Agnew Lake intrusions, continued through the 1980’s (e.g. James and
Born, 1985; McCrank et al., 1989) and 1990’s (e.g. Peck and James, 1990; Peck et al.,
1993a). However, it was not until the mid to late 1990’s that base metal and PGE
exploration interests began to shift toward the River Valley intrusion, due in part to the
work of Ashwal and Wooden (1989). Since 1999, the mafic intrusions of the East Bull
Lake intrusive suite, and especially the River Valley intrusion, have been the subject of
ongoing Cu-Ni-PGE mineral exploration. It is this increased economic interest in these
intrusions that has led to a renewed academic interest in the geology, stratigraphy,
geochemistry and mineralogy of the East Bull Lake suite. Moreover, understanding the
geology of the East Bull Lake intrusive suite is of significant importance in
understanding the earliest evolution of the Palaeoproterozoic Southern Province in central
Ontario and there are now numerous professional publications that describe and discuss
the geology, geochemistry, and mineral deposit potential of these intrusions (e.g. James et
al. 2002a, 2002b; Easton, 2000a, 2003).
6.2 General Geology of the River Valley Intrusion
The River Valley intrusion is best exposed in Dana Township (Fig. 6-1) where it
locally exhibits well preserved primary mineralogy and textures and has been the subject
of several recent studies (Easton and Hrominchuk 1999, 2001a, 2001b; James et al.,
2002a, 2002b; Easton 2003; Easton et al., 2004). In comparison to the other East Bull
Lake suite bodies, the River Valley intrusion shows the clearest relationships with other
members of the Palaeoproterozoic rifting suite (Easton et al., 2004). However, studies on
the stratigraphy, geochemistry and mineralization in the River Valley intrusion are
limited in comparison to similar studies on the East Bull Lake (Peck et al., 1993a, 1995,
2001) and Agnew Lake (Vogel et al., 1998a, 1999) intrusions.
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Figure 6-1. General geological map of the River Valley intrusion illustrating the
distribution of stratigraphic zones that form the bulk of the intrusion and locations of
principal PGE sulphide mineralization and occurrences. Many of the northeast-trending
faults (dashed lines) are fault or shear zones that range from a few metres to 10’s of
metres in width. The Dana Lake Shear Zone is considered part of the Grenville Front
Boundary Fault system (solid lines). North of the Sturgeon River Fault Zone, the
intrusion contains large areas of preserved or partly-preserved primary mineralogy,
whereas south of the Sturgeon River Fault, in Crerar Township, the intrusion is
thoroughly recrystallized to upper amphibolite facies rock assemblages (modified after
James et al., 2002b).
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The River Valley intrusion is cut by mafic dikes that are geochemically correlated with
the Hearst-Matachewan Dike Swarm, as well as by felsic intrusive rocks coeval with the
Huronian Supergroup volcanic rocks (Easton and Hrominchuk 1999, 2001b). In addition,
granitic rocks in Street Township, located about 20 km west of the River Valley
intrusion, are dated at 2460±20 Ma and contain inclusions of East Bull Lake suite rocks
(James et al., 2002a). Similar inclusions were also reported by Easton (2003) in granitic
rocks in Henry and Loughrin townships, located immediately east of Street Township.
The River Valley intrusion is also cut by magnetite-olivine diabase dikes of the 1238 Ma
Sudbury Dike Swarm and the 590 Ma Grenville Dike Swarm (Easton, 2000a).
6.2.1 External Contacts
The identification of primary igneous contacts between lithological units, in
particular those that form boundaries to the Marginal Series which hosts the potentially
economic PGE-Cu-Ni sulphide mineralization (Fig. 6-1), is essential to successful
mineral exploration in the River Valley intrusion. Easton (2003) noted that three main
contact types are present between the River Valley intrusion and country rock units in
Dana Township, viz: 1). preserved intrusive contacts; 2). tectonized or disrupted intrusive
contacts, and, 3). wholly tectonic or fault contacts. It is likely that most of the northern
contact of the River Valley intrusion in Dana Township is primary, however, as the
contact is followed southeast it becomes more difficult to confirm the presence of a
primary contact, mainly due to a lack of exposure. In the northwest quadrant of Dana
Township, in the area of Pacific North West Capital Corp.’s Dana North, Dana South,
Lismer’s Ridge North and Lismer’s Ridge South deposits, the north-northeastern contacts
of the intrusion are interpreted as primary, although they are locally cut, with minimal
lateral offset (generally <50m horizontally), by relatively narrow (10’s to 100’s of metres
wide) northeast striking mylonitic zones that are related to the Grenville Front Tectonic
Zone (Fig. 6-1). The nature of the intrusive contact in the area of Azen Creek and
eastward toward the McWilliams Township line is much more obscure as the structures
(faults, folds?) within this region of the intrusion become much more complex.
Easton (2003) suggested that the western contact of the River Valley intrusion, along
Highway 805, in the southern half of Dana Township represents a tectonized igneous
contact and may represent an upper, rather than a basal, contact of the intrusion (Photo 6-
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1a). The northwestern contact is tectonic and is complicated by the presence of several
faults relating to the Grenville Front Boundary Fault, which obscure the relationship
between the River Valley intrusion and the Huronian Supergroup rocks (Fig. 6-1). In this
region, the River Valley intrusion is either in thrust contact with quartzite of the
Mississagi Formation (Davidson 1986) or is in an unclear contact relationship with
bimodal (mafic-felsic) metavolcanic rocks of the lower Huronian Supergroup (Easton and
Hrominchuk, 1999). Easton and Hrominchuk (1999) suggested that the metavolcanic
rocks are ~2460 Ma in age (geochemical correlation) and were therefore probably
deposited post-emplacement of the River Valley intrusion; this supports the interpretation
that the River Valley intrusion is in thrust contact with Huronian Supergroup rocks in this
area.
6.2.2 Country Rocks
Easton (2003) grouped the country rocks to the River Valley intrusion into four
gneissic associations (Culshaw et al., 1988). These units, from northwest to east, are: the
Front, Street, Crerar, Pardo gneiss associations. Easton (2003) considered these four
gneissic associations to represent a southward-deepening section of crust, with exposure
of each section likely the result of north-northwest-directed transport along Grenville-age
thrust faults. Of these four associations, the Pardo gneiss is most relevant to this study as
it lies alongside the northern contact of the River Valley intrusion in Dana Township
(Fig. 6-1). On the basis of field observations and geochemistry, Easton (2003)
considered a fifth gneissic unit, the Red Cedar Lake gneiss, to be a more deformed
(flattened) and cataclastic equivalent of the Pardo gneiss, probably as a result of increased
Grenvillian deformation, and suggested their formation to be between 2685 and 2675 Ma.
The Pardo gneiss consists mainly of fine-grained, biotite quartzofeldspathic gneiss
(metagreywacke) cut by granodioritic and tonalitic leucosome veins (5-25% of the rock)
and medium-grained, granodioritic to monzogranitic gneiss, possible representing
plutonic rocks that intruded the metasedimentary migmatites (Easton, 2003).
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Photo 6-1. (A) Tectonized contact along the western margin (Grenville Front Boundary Fault) of the intrusion, Highway 805, Dana Township. The arrow indicates the plane of foliation. The pen is about 15 cm long. (B) Chaotic Zone, correlative with the Marginal and/or Inclusion/Autolith-bearing zones, was identified by Mustang Minerals Corp. in the eastern part of Dana Township. An eight centimetre ruler is provided for scale.
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Lumbers (1973) mapped metagreywacke and granodiorite immediately north of the
Grenville Front Boundary Fault in Pardo Township, and it is probable that these rocks
represent non-migmatized equivalents of the Pardo gneiss, preserved at higher structural
levels (Easton, 2003). Easton (2003), noting that the gneissosity and folds in the Pardo
gneiss are cut by both Matachewan and Sudbury dike swarms, suggested that the main
migmatitic event affecting the Pardo gneiss occurred prior to 2445 Ma and was likely
Neoarchaean in age. Easton (2003) also noted that the area underlain by the Pardo gneiss
was affected by high-grade metamorphism after 1240 Ma. At several localities along the
northern contact of the River Valley intrusion, Pardo gneiss immediately in contact with
River Valley intrusion rocks show a higher degree of migmatization over several metres
away from the contact, suggesting that contact metamorphism was responsible for further
deformation of the proximal Pardo gneiss.
6.2.3 Structure, Deformation and Metamorphism
Within the River Valley intrusion, in Dana Township, numerous northeast-trending
linear zones of alteration and deformation, generally less than 1 km wide and typically
10’s to 100’s of metres wide, dissect the igneous stratigraphy (Fig. 6-1). These discrete
linear domains comprise steeply-dipping, gneissic rocks (mylonitic) that confine
generally northwest-trending regions or “cores” of relatively unaltered and/or preserved
intrusive rocks that can be kilometres in length, and include preserved magmatic textures,
mineralogy and mineralization within the Marginal Series rocks.
In the northernmost part of the intrusion, in the Dana Lake and Lismer’s Ridge areas,
there is an increase in metamorphic grade southeast into the main Grenville terrain,
ranging from greenschist in the Dana Lake area to amphibolite facies or higher in the
Lismer’s Ridge area, a distance of about 5 km (Fig. 6-1). Moving further southeast along
the contact region, the metamorphic grade increases from upper amphibolite in the Azen
Creek area to granulite facies toward Razor and into McWilliams Township (Fig. 6-1).
The Neoproterozoic to Early Paleozoic Sturgeon River Fault Zone (Fig. 6-1) is an
important northwest-trending structural feature that cuts through the River Valley
intrusion. North of the Sturgeon River Fault, the River Valley intrusion contains large
areas of preserved or partly-preserved primary mineralogy, and deformation is
concentrated along discrete vertical and sub-horizontal shear zones that cut the intrusion
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(Easton and Hrominchuk 1999, 2001b; Hrominchuk 2000). The geometry of the
intrusion north of the Sturgeon River appears to be sheet-like, with igneous layering
generally dipping at 20-30° to the south and southeast (Easton et al., 2004). This
configuration has led to the exposure of the basal contact and/or margin and/or sidewall
of the River Valley intrusion (Marginal Series rocks) for about 10 km along the north and
northeastern margin of the intrusion (Dana Township), providing an extensive
exploration target area for contact-type PGE-Cu-Ni mineralization (Fig. 6-1).
South of the Sturgeon River Fault, in Crerar Township, the River Valley intrusion
consists of a moderately dipping (40-60°), synformal sequence that is more thoroughly
recrystallized to upper amphibolite facies assemblages than the rocks in Dana Township
(Easton and Hrominchuk, 1999, 2001a). Grenvillian deformation is principally
concentrated near the Grenville Front Boundary Fault, along the west side of the
intrusion; work by Tettelaar (2000) and Easton and Hrominchuk (1999), estimated
Grenvillian metamorphic conditions to be 5-7 kb and 625°C.
6.3 Stratigraphy, Mineral Chemistry and Petrography
Easton (2003) presented generalized cross-sections for the East Bull Lake suite
intrusions, correlating the exposed stratigraphy of the northern and southern parts of the
River Valley intrusion with the lower stratigraphy of the East Bull Lake and Agnew Lake
intrusions. Hrominchuk (2000) proposed an estimated 900 m thick stratigraphy for the
northern part of the River Valley intrusion, which is in Dana Township, north of the
Sturgeon River Fault (Fig. 6-1). In this interpretation, the River Valley intrusion consists
of an inclusion-bearing Marginal Zone, which hosts most of the mineralization in the
intrusion, overlain by layered, mainly melanocratic, rocks of the Olivine Gabbronorite
Zone, which are in turn overlain by progressively fractionated rocks of the Gabbronorite
and Leucogabbronorite zones. An autolith-bearing unit, termed the Inclusion/Autolith-
bearing Zone (Hrominchuk, 2000), intrudes the lower Gabbronorite Zone, and like the
Marginal Zone is mineralized (e.g. Azen Creek, Fig. 6-1). Marginal Zone and
Inclusion/Autolith-bearing Zone rocks form a discontinuous, typically disordered and
heterogeneous magmatic assemblage, occurring where primary intrusion contacts are
preserved, and are host to much of the mineralization discovered to date; the Marginal
Zone (Hrominchuk, 2000) is encompassed by rocks of the Marginal Series (see Section
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6.5). Some specific features of these zones are as follows (Hrominchuk, 2000; James et
al., 2002b; Easton, 2003):
1. Marginal Zone (Marginal Series): ~100 m thick, consisting of mineralized
gabbronorite with fragments (gabbronorite/pyroxenite) and scarce footwall
xenoliths (gneisses/granitic). The matrix is composed of primocrysts of
plagioclase (An81-39), inverted pigeonite (En76-44) and augite. Fragments are
variable in size, ranging from metres to decametres in maximum dimension, and
commonly obscure the location of the contact. Small but widespread amounts of
white and/or blue-grey quartz and plagioclase with up to ~An40 compositions
(sodic), suggest local magma contamination. This zone represents the primary
exploration target for PGE-Cu-Ni sulphides comprising PGE-rich disseminated
chalcopyrite, pyrrhotite and pentlandite mineralization (1-5%) which occur in the
matrix assemblage (~70%) and less commonly (~30%) in the mafic fragments.
Fragment-bearing rocks decrease rapidly away from the base of this zone,
generally over widths of about 25-50 m (maximum widths of ~100 m).
2. Olivine Gabbronorite, Gabbronorite and Leucogabbronorite zones: ~700 m
thick sequence of progressively fractionated rock compositions from olivine
melagabbronorite to leucogabbro and anorthosite. The Olivine Gabbronorite
Zone consists of decametre thick, metre-scale layered sequences of troctolite,
melatroctolite and olivine gabbronorite (primocryst olivine, inverted pigeonite,
plagioclase). The Gabbronorite Zone consists of thick, weakly layered or
discontinuously layered norite and gabbronorite (primocryst inverted pigeonite,
plagioclase, ± augite). Leucogabbronorite dominates the Leucogabbronorite Zone
which also consists of massive but localized anorthositic rocks (primocryst
plagioclase, augite, ± orthopyroxene). The compositions of the primocrysts
(plagioclase (An78-56), olivine (Fo76-72), orthopyroxene (En76-56)), and their
stratigraphic distribution above the Marginal Zone, suggests that the upper portion
of the original River Valley intrusion is missing due to tectonism and/or erosion
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(James et al., 2002b). This contrasts with the igneous stratigraphy of the Agnew
Lake intrusion, which is largely intact (Vogel et al., 1998a).
3. Inclusion/Autolith-bearing Zone: intrudes the lower/marginal ~300 m portion of
the River Valley intrusion. At Azen Creek (Fig. 6-1), this zone occurs within
about 300 m of the north contact of the intrusion. This zone is dominated by
fragments of rock types that comprise the Marginal, Olivine Gabbronorite, and
Gabbronorite zones, as well as minor footwall xenoliths. The matrix, consisting
of primocryst olivine (~Fo68), plagioclase (An73-68) and inverted pigeonite (En69-
55), is more mafic in composition than the Marginal Zone which lack olivine.
Like the Marginal Zone, the matrix of the Inclusion/Autolith-bearing Zone
contains PGE that are associated with disseminated chalcopyrite, pyrrhotite and
pentlandite mineralization.
In the eastern part of Dana Township and into McWilliams Township, Pacific North
West Capital Corp. and Mustang Minerals Corp. have identified PGE mineralization
associated with 0.5-5% disseminated chalcopyrite, pyrrhotite and subordinate pentlandite.
This mineralization is hosted by what Mustang Minerals Corp. have termed the “Chaotic
Zone” (PGE occurrence 7, Fig. 6-1; Photo 6-1b). This zone appears to be correlative
with the Breccia Unit of the Marginal Series, is 25-150 m wide in plan view and is
continuous for about 3 km along strike, extending northwest into the Razor PGE
occurrence (PGE occurrence 6, Fig. 6-1). James et al. (2002b) described the Chaotic
Zone matrix as consisting of equigranular, poikilitic and pegmatitic gabbronorite and
melagabbronorite. Autoliths form 50% or more of rocks in this zone and range in
composition from websterite and orthopyroxenite to gabbronorite and anorthosite in
which orthopyroxene, clinopyroxene and plagioclase are the primocryst phases. Mustang
Minerals Corp. have also identified layered olivine-bearing rocks, olivine websterite to
troctolite in composition, which overly the Chaotic Zone and may be correlative with the
Olivine Gabbronorite Zone (Hrominchuk, 2000) and the PGE occurrence at Azen Creek
(PGE occurrence 4, Fig. 6-1).
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6.4 General Geochemistry
The geochemistry of River Valley intrusion rocks is similar to that of other East Bull
Lake suite intrusions; geochemical data for rocks from the River Valley intrusion can be
found in Hrominchuk (2000), Easton and Hrominchuk (2002), James et al. (2002a) and
Easton (2003). A summary of the geochemical features as presented by Hrominchuk
(2000) and Easton et al. (2004) is as follows:
1. Marginal Zone: generally <50 wt% SiO2 and CIPW quartz-normative. Rocks
show much higher Ti, Fe, Rb, Sr, K, Na, P, Ba, Zr and Y contents than in the
overlying units and this is interpreted to be the result of contamination, probably
through wall rock assimilation.
2. Olivine Gabbronorite Zone: olivine-normative rocks, characterized by high
MgO (15-24 wt%) and low SiO2 (38-45 wt%), with anomalous Ni contents
attributed to primocryst olivine.
3. Inclusion/Autolith-bearing Zone: matrix composition is elevated in Mg, Ca, Al,
and Fe, which is consistent with its plagioclase, orthopyroxene and olivine-
dominated mineralogy. The fragments, inclusions and xenoliths of this zone are
extremely varied in composition, partially resorbed and commonly mineralized.
Mafic inclusions are similar to the rocks in the lowest part of the layered Olivine
Gabbronorite Zone.
4. Gabbronorite Zone: gradual fractionation to Si-, Al-, Ca-, Na-, K-rich and Mg-
poor compositions; a trend also observed in the uppermost Leucogabbronorite
Zone.
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Figure 6-2. Generalized geology of the northwest portion of the River Valley intrusion
showing the locations of the (1) Dana North, (2) Dana South, (3) Lismer’s North, and (4)
Lismer’s South PGE-Cu-Ni deposits. Also shown are the approximate locations and
projections of drill holes (A) RV00-22 and (B) DL-14, 15 and 16 (modified after James et
al., 2002b).
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6.5 Marginal Series Stratigraphy, Mineralization and Geochemistry
To date, four contact-type PGE-Cu-Ni deposits have been outlined along the
northern margin of the River Valley intrusion in Dana Township; from northwest to
southeast they are; Dana North, Dana South, Lismer’s North and Lismer’s South (Fig. 6-
2). Small, plug-like alkaline intrusions of unknown age, but considered by Easton (2003)
to be Archaean (2640 Ma), occur along the intrusive contact where they displace the
Marginal Zone rocks (Fig. 6-2). As well, faults related to the Grenville Front Boundary
Fault and a 1.24 Ga Sudbury Dyke Swarm olivine-magnetite gabbro dike cut or displace
the Marginal Zone (Fig. 6-2). Silicate assemblages that host the mineralization in this
part of the River Valley intrusion range from greenschist facies assemblages in the
northwest to amphibolite facies in the southeast, contrasting with the preserved magmatic
assemblages and/or textures that dominate the upper amphibolite to granulite facies
mineralogy in the remainder of the intrusion toward the south-southeast (Fig. 6-1).
A detailed stratigraphy for the variably mineralized Marginal Series rocks has been
developed by the author, on the basis of outcrop mapping and greater than 80,000 metres
of diamond drill core logging as part of the exploration work carried out under author’s
direction (Fig. 6-3). Average PGE and base metal concentrations for the Marginal Series
rocks are provided in Table 6-1. The Marginal Series is in abrupt, intrusive contact to the
east with Neoarchaean-age Pardo gneiss, and bounded to the west by a sequence of
weakly layered to massive leucogabbro, gabbro and melagabbro. The Marginal Series,
which includes the Marginal Zone as described by Hrominchuk (2000), consists of four
distinct units that are capped by the Layered Units and is normally ~100 m wide in plan
view but generally ranges from 10 to 50 metres in width (Fig. 6-3).
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Figure 6-3. Schematic of typical stratigraphy through the Marginal Series rocks
(Marginal Zone) in the River Valley intrusion. The stratigraphy is largely based on the
more than 50,000 metres of diamond drill core from the Dana Lake and Lismer’s Ridge
areas. The Breccia Unit, the primary target for potentially economic PGE-Cu-Ni
mineralization, consists mainly of autoliths (black fragments), with very (<<1%) few
xenoliths (modified after James et al., 2002b).
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Unit n Data Au Pt Pd Ni Cu Pd:Pt Cu:Nippb ppb ppb ppm ppm
*Layered Units 277 average 6.0 22.0 19.4 97.1 70.2 0.8 0.9(LU) median 5.0 20.0 14.0 83.0 78.1 0.7 0.9Inclusion-Bearing Unit 691 average 11.2 60.5 78.0 84.4 122.1 1.1 1.7(IBZ) median 7.0 34.0 32.0 70.0 80.7 0.9 1.1Breccia Unit 2317 average 53.2 253.1 707.2 166.4 803.6 2.3 4.8(BX) median 28.0 120.0 246.0 119.0 517.0 2.3 4.4Boundary Unit 185 average 9.7 45.6 102.4 116.6 223.6 1.9 2.5(BZ) median 7.0 26.0 43.0 87.0 169.0 1.8 1.9Footwall 197 average 6.9 8.9 8.7 120.9 75.5 0.7 0.8(FW) median 4.0 0.0 5.0 129.0 72.7 0.5 0.6Mafic Dikes 68 average 19.2 51.3 109.9 97.4 280.6 1.3 2.8
median 8.0 21.0 17.0 45.0 142.5 0.9 2.7*Mafic Dikes-2 21 average 22.9 19.0 15.7 54.7 42.9 0.8 1.0
median 10.0 19.0 16.0 43.0 40.9 0.7 0.9Felsic Dikes 22 average 10.3 29.9 54.4 24.3 174.2 1.2 7.3
median 9.0 18.0 16.5 16.0 70.3 0.8 3.5 Table 6-1. Average and median values and metal ratios for whole-rock precious and base
metal concentrations from Marginal Series and associated rocks, River Valley Intrusion.
The Layered Units were calculated using samples with <100 ppm Cu (assumed low
sulphur); data from drill core analyses supplied by Pacific North West Capital Corp. and
Anglo American Platinum Corporation Limited. *Averages from the Layered Units and
Mafic Dikes-2 are used as estimates of parental magma compositions – see text for
discussion.
332
From the footwall Pardo gneiss (Photo 6-2a), westward into the intrusion, the sequence
and character of the four distinguishable units in the Marginal Series (Photos 6-2 to 6-5)
are:
1. Footwall Breccia Unit (FBX): 5 to 15 metres wide, but may be absent. Consists
of partly rounded to angular, centimetre- to decimetre-size fragments of country
rock (~75% - Pardo gneiss, Archaean gabbro, diabase, diorite) and River Valley
intrusion material (~25% - chilled gabbro and medium-grained melagabbro) in a
matrix of finer grained rock of similar composition and/or aplitic/granitic matrix.
A narrow zone of migmatite at the contact of the intrusion is likely due to contact
metamorphism, and granitic veins can be traced from the Footwall Breccia Unit
into the footwall gneiss. Sulphides are dominantly pyrite and pyrrhotite with
local areas of trace to 1% chalcopyrite + pyrrhotite; PGE concentrations are
normally <25 ppb. The contact between this unit and the overlying Boundary
Unit is gradational, marked by a gradual decrease in the ratio of xenoliths
(country rock fragments) to autoliths (primarily chilled gabbro?) derived from
River Valley intrusion rocks.
2. Boundary Unit (BZ): 5 to 20 metres wide, but may be absent (Photo 6-2b).
Consists of partly rounded to subangular, centimetre- and decimetre-size
fragments of country rock (typically 10-25%), and autoliths of melagabbro,
gabbro and less commonly leucogabbro to anorthosite in a matrix of gabbro to
melagabbro ± aplite/granite, as in the Footwall Breccia Unit. The footwall
xenoliths (mainly alkali granites and granodiorite-tonalite) in the Boundary Unit,
and in the Footwall Breccia Unit, share many similarities to those described by
Peck et al. (2001) for xenoliths in the Border zone of the East Bull Lake intrusion.
In particular, at the River Valley intrusion there is also evidence of in-situ melting
such as granophyric xenomelts in or proximal to the country rock xenoliths and
fragments. Sulphide minerals are mainly pyrite and pyrrhotite, with locally up to
3% chalcopyrite + pyrrhotite; PGE concentrations are typically <75 ppb with
local concentrations >1000 ppb. The contact between this unit and the overlying
333
Breccia Unit is sharp to gradational, marked by an abrupt to gradual decrease in
the occurrence of country rock fragments, which become near-absent in the
Breccia Unit.
3. Breccia Unit (BX): in general 20 metres wide but ranges to >100 metres wide
(Photo 6-3). This unit contains as much as 95% fragments that are dominantly
fine-grained gabbro to melagabbro with subordinate medium- to coarse-grained
gabbro and leucogabbro. On the basis of field observations, it is not clear whether
these fragments are autoliths derived locally or from elsewhere in the River
Valley intrusion, or if they are xenoliths. The fragments are hosted by a medium-
grained matrix of similar composition; matrix compositions vary abruptly from
melagabbro to gabbro to leucogabbro over very short distances. Fragments are
partly rounded to rounded, most likely as a result of partial assimilation, and
centimetre to decimetre in size – those greater than a metre (rafts and possibly
pendants) are mainly xenoliths of footwall compositions (gneiss) and these
fragments tend to be larger with increasing proximity to the intrusive contact; a
single fragment of layered gabbroic rocks, presumably derived from the Layered
Units, was observed at the South Zone (Fig. 6-12b). Sulphide minerals comprise
1 to 5% pyrrhotite + chalcopyrite and occur as both blebby and disseminated
textures; PGE contents are highly varied, but most values range from 500-6000
ppb with local concentrations >10,000 ppb. Blue-grey quartz is commonly
associated with sulphide accumulations and higher than average PGE
concentrations suggesting assimilation of local country rock; Peck et al (2001)
attributed the presence of blue quartz to a metasomatic event that was restricted to
the margins of the East Bull Lake intrusion. Notably, the Breccia Unit, which
contains the highest and most persistent PGE-rich sulphide mineralization, has the
smallest proportion of footwall inclusions (<<1%), perhaps an indication that
magma contamination through assimilation of local country rocks is not a major
controlling factor on mineralization (James et al., 2002b). The contact between
the Breccia Unit and the overlying Inclusion-bearing Unit is abrupt, marked by a
rapid increase in the occurrence of felsic autoliths (derived from the overlying
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Layered Units) and a decrease in fine-grained mafic fragments mafic, an increase
in overall fragment size, a decrease in the ratio of fragment to matrix volume, and
a decrease in the volume percent of visible sulphide.
4. Inclusion-bearing Unit (IBZ): 10 to 50 metres wide (Photo 6-4a). This unit
contains >90% autoliths of leucogabbro, subordinate gabbro and lesser
melagabbro in a matrix of either medium-grained leucogabbro or gabbro; the
leucogabbro xenoliths are subangular to partly rounded, dominantly decimetre to
metre in scale, and appear to be inclusions that were stoped from the overlying
Layered Units (the Leucogabbronorite Zone of Hrominchuk, 2000). Sulphide
minerals include trace to 3% pyrrhotite + chalcopyrite; PGE contents range from
100-500 ppb with local concentrations >1000 ppb. The contact between the
Inclusion-bearing Unit and the overlying Layered Units is gradational, marked by
a decrease in recognizable fragments and finally the presence of massive rock
units.
In the Dana Lake area, the overlying Layered Units (LU) consist of massive leucogabbro
and gabbro with subordinate melagabbro. In general, metre- to decametre-scale modal
and textural layering is poorly developed and contacts between layers are almost always
gradational (Photo 6-5). The LU contain only trace (<<1%) sulphide minerals
(chalcopyrite + pyrrhotite) but have PGE concentrations that are anomalous (~22 ppb Pt,
19 ppb Pd) in terms of average mafic rocks (Hamlyn et al., 1985).
Fine-grained gabbro and diabase dikes cut all of the above units as well as the
Layered Units (the Leucogabbronorite Zone of Hrominchuk, 2000) in the main part of the
intrusion (Photo 6-4b). These dikes are metamorphosed at a grade similar to the River
Valley intrusion in the Dana North area, are distinct from younger dikes of the Sudbury
and Grenville swarms (Easton, 2003) and many are plagioclase-phyric, suggestive of
Matachewan Swarm dikes.
An east-west cross section through the Dana South PGE-Cu-Ni Deposit is shown in
Figure 6-4; this section is based on mapping of surface geology and data from more than
40 drill holes in the immediate area (South Zone). The data suggest that the dip of the
335
contact of the IBZ and BX with the footwall gneiss in this area ranges from about 65° to
75° west (inward towards the intrusion). However, this dip is highly variable along strike
changing from 65° to 85° west to 65° to 85° east over strike distances of <100 metres; it
is unclear as to whether this variability is a primary feature or is the result of folding.
The attitude of metre-scale layering in the Layered Units (the Leucogabbronorite Zone of
Hrominchuk, 2000) adjacent to the IBZ or BX is poorly constrained but is estimated to be
at ~60-70° west, and possibly shallowing (i.e. <60° dip) westward into the intrusion.
Figure 6-4. Schematic geological section (east-west, looking north) through the
mineralized Dana South deposit. This section is based on data from drill holes DL-14,
DL-15, and DL-16; intersections of sulphide mineralization through the Breccia Unit are
shown as 3E = Pt+Pd+Au (modified after James et al., 2002b).
336
Photo 6-2. (A) Typical footwall (hangingwall) paragneiss to the River Valley Intrusion. The Canadian 25 cent piece is about 2.2 cm in diameter. (B) Boundary Unit with light coloured granitic matrix and fine-grained mafic fragments, Lismer’s Ridge area. The hammer handle is about 70 cm long.
337
Photo 6-3. (A) Breccia Unit with medium-grained mafic matrix and fine-grained mafic fragments (xenoliths?) from the South Zone, Dana South Deposit. The hammer handle is about 33 cm long. (B) Breccia Unit with medium- to coarse-grained gabbro-leucogabbro matrix and fine- to medium-grained mafic fragments (xenoliths?) from the Central Zone, Dana North Deposit. The pencil is about 18 cm long.
338
Photo 6-4. (A) Inclusion-bearing Unit with fine- to medium-grained mafic matrix and medium- to coarse-grained fragments (autoliths) of gabbro-leucogabbro from the South Zone, Dana South Deposit. The hammer handle is about 30 cm long. (B) Fine-grained (diabase) mafic dike cutting through the Breccia and Inclusion-bearing units from the South Zone, Dana South Deposit; the smaller dike is cutting through a felsic fragment (autolith) from the Inclusion-bearing Unit. The hammer handle is about 70 cm long.
339
Photo 6-5. (A) Modal and textural layering in olivine gabbronorite from the Razor area, southeast Dana Township. The pen magnet is about 12.5 cm long. (B) Flat-lying layering in olivine gabbronorite from the region south of the Azen Creek Zone, south-central Dana Township. The hammer handle is 33 cm long.
340
In Figure 6-4 anomalous PGE values (>500-1000 ppb Pt and/or Pd) occur throughout the
length of all three drill holes and higher-grade intersections are indicated, typically
occurring as a “core” area within the lower one-third of the mineralized zone. Similar
geology, geometry and mineralization occurs within the Marginal Series rocks at the
Dana North PGE-Cu-Ni Deposit (Fig. 6-2).
6.5.1 General Geochemistry
Average and median PGE-Cu-Ni concentrations for mineralized and unmineralized
samples from the Marginal Zone in the River Valley intrusion are listed in Table 6-1.
Data from sulphide-bearing felsic and mafic dykes and the BZ, BX and IBZ all show
moderate to high average Pt+Pd, reaching a maximum in the BX. Samples from the IBZ,
BX, and BZ have average Pd/Pt and Cu/Ni ratios of 1.1 to 2.3 and 1.7 to 4.8,
respectively, which is distinctive from the low sulphide, Cu-poor assemblages of the LU
and Mafic Dikes-2 (Table 6-1); two samples from the latter have average Pd/Pt and
Cu/Ni ratios of 0.8 and 0.95, respectively. The concentrations of PGE in the
unmineralized and mineralized samples are similar to those reported in the East Bull
Lake (Peck et al., 1995) and Agnew Lake intrusions (Pacific North West Capital Corp.
and Anglo American Platinum Corporation Limited, unpublished data). Footwall rocks
have low Pt, Pd and Au (average = 24.4 ppb Pt+Pd+Au), and Pd/Pt and Cu/Ni are <1
(Table 6-1).
Metal values for unmineralized rocks (i.e. samples with <100 ppm Cu and/or <0.05
wt% S) that form large parts of the intrusion and/or which are feeders, are provided by
data from the LU and Mafic Dikes-2 in Table 6-1. These rocks have anomalous PGE
concentrations, averaging ~34-41 ppb Pt+Pd, and their metal ratios, Pd/Pt and Cu/Ni, are
both <1, which is unlike the mineralized samples from the IBZ (~139 ppb Pt+Pd, 1.1
Pd/Pt, 1.7 Cu/Ni) and BX (~960 Pt+Pd, 2.3 Pd/Pt, 4.8 Cu/Ni). Similar PGE
concentrations of 7 ppb Pd and 13 ppb Pt (20 ppb Pt+Pd) are reported from
unmineralized mafic rocks from below the J-M Reef in the Stillwater Complex, Montana
(Peck and Keays, 1990).
Chondrite-normalized PGE diagrams (recalculated to metals in 100% sulphide) for
mineralized (3-5% pyrrhotite + chalcopyrite) and unmineralized samples (<100 ppm Cu
341
and/or <0.05 wt% S) from the Dana Lake and Lismer’s Ridge areas are presented in
Figure 6-5.
Figure 6-5. Chondrite-normalized (metals in 100% sulphide) diagram comparing data for
contact-type sulphide mineralization from the Lower Series rocks at East Bull Lake
intrusion (EBLI) and mineralized and non-mineralized rocks from the River Valley (RVI)
intrusion with chalcophile data from the J-M Reef (Stillwater) and the Portimo Complex,
Finland. River Valley data are averages (6 samples) from the Dana Lake and Lismer’s
Ridge areas (after James et al., 2002b). Also included for comparison is structurally
controlled sulphide mineralization from the East Bull Lake intrusion (Parisien Lake
Deformation Zone).
Metal abundances and patterns for mineralized samples from the River Valley intrusion
are very similar to those from the East Bull Lake intrusion, and both data sets show
patterns and absolute abundances that are similar to contact-type, low sulphide PGE
mineralization at the Konttijarvi-Portimo Complex, Finland (Alapieti and Lahtinen,
342
2002) and sulphides from the J-M Reef, Stillwater, USA (Barnes and Naldrett, 1985),
both of which are accepted to be magmatic, sulphide-associated PGE deposits. Samples
with trace mineralization show a wide variation in PGE abundance and the pattern from
an average of six unmineralized samples, shown in Figure 6-5, shows a pattern not unlike
the mineralized samples; this suggests that the mineralized and unmineralized rocks are
genetically related. Overall, the PGE patterns are consistent with those of magmatic
sulphides and contrast sharply with the hydrothermal pattern exhibited by structurally-
controlled sulphide mineralization from the Parisien Lake Deformation Zone in the East
Bull Lake intrusion (Peck et al., 1993a).
6.6 Petrology and Geochemistry of Drill Hole RV00-22
Diamond drill hole RV00-22, located in the area of the Dana North deposit, was
completed in July 2000 as part of the initial exploration drilling program by Pacific North
West Capital and Anglo American Platinum Corporation Limited (Fig. 6-2). The drill
hole, drilled at an inclination of 45° toward 86° and totalling 259 m, was collared in the
massive Layered Unit and continued through the Inclusion-bearing, Breccia, Boundary,
and Footwall Breccia units, terminating in the Footwall rocks. A summary of the
stratigraphy recorded in the drill core of RV00-22 and some of the principal geochemical
features are provided in Tables 6-2 and 6-3; the drill core log and complete assay results
are provided in Appendix 3. Selected photographs of the drill core are provided in
Photos 6-6 to 6-9.
Two data sets were compiled from the core samples. The first, referred to as Group-
1, consists of 112 core samples, with ninety-nine of these samples coming from the
logging and sampling efforts of Pacific North West Capital Corp. geologists, sampling at
approximately 1-2 m intervals; these core samples were analyzed for Pt, Pd, Au, Cu and
Ni at XRAL Laboratories and S, Se at the Geoscience Laboratories in Sudbury.
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Unit From To Int n Samples Rock Type(m) (m) (m)
LU 2.50 89.50 87.00 27 22690 to 29642 melagabbro, gabbro, leucogabbro;rare, crude layering
IBZ 91.00 160.80 69.80 20 29643 to 29683 pegmatitic leucogabbro-gabbroBX 160.80 224.93 64.13 55 29684 to 29753 melagabbro-gabbro-leucogabbro fragments in
gabbroic matrix; blue quartz patches and biotiteBZ 229.00 233.20 4.20 4 29754 to 29759 felsic fragments, felsic dykes;
gabbro matrix and gabbro dykesFBX 233.20 241.50 8.30 3 29760 to 29764 felsic gneiss; sheared gabbro
FW 244.00 256.00 12.00 3 RV22-01, 02, 03 felsic gneiss; sheared gabbro Table 6-2a. Summary of drill core log for drill hole RV00-22, Dana Deposit (North),
River Valley intrusion.. LU = Layered Units, IBZ = Inclusion-Bearing Unit, BX =
Breccia Unit, BZ = Boundary Unit, FBX = Footwall Breccia; n = number of samples.
Unit *Avg. 3E Avg. Cu Avg. Ni Pd/Pt Cu/Ni Pd/Cu(ppb) (ppm) (ppm)
LU 61 457 131 0.6 3.5 10620
IBZ 223 63 47 1 1.8 713BX 2380 1317 256 2.7 5.1 1144
BZ 197 217 145 2.2 1.9 3236
FBX 44 82 138 1.6 0.6 16354
FW 6 72 175 1.2 0.4 73937
Table 6-2b. Summary of important whole-rock chalcophile averages and ratios for drill
hole RV00-22, Dana Deposit (North), River Valley intrusion. Values for 3E = Pt+Pd+Au;
LU = Layered Units, IBZ = Inclusion-Bearing Unit, BX = Breccia Unit, BZ = Boundary
Unit, FBX = Footwall Breccia. See Appendix 1 for complete data listing.
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Se S Ni Ir Ru Rh PtUnit ppb wt% ppm ppb ppb ppb ppb
Layered (n=8) A 219 0.06 189.00 0.72 1.13 1.06 16.01metal in 100% sulphide B 36.50 114975.00 438.00 687.42 644.83 9739.42Inclusion-bearing (n=6) A 73 0.02 40.00 2.88 1.75 10.93 99.08metal in 100% sulphide B 36.50 73000.00 5256.00 3193.75 19947.25 180821.00Breccia (n=9) A 2093 0.33 321.00 13.88 4.84 45.39 663.61metal in 100% sulphide B 36.50 35504.55 1535.21 535.33 5020.41 73399.29Boundary (n=1) A 598 0.15 94.00 1.46 0.87 8.50 68.30metal in 100% sulphide B 36.50 22873.33 355.27 211.70 2068.33 16619.67Footwall Breccia (n=1) A 292 0.43 123.00 0.19 0.36 0.69 3.53metal in 100% sulphide B 36.50 10440.70 16.13 30.56 58.57 299.64Footwall (n=3) A 226 0.36 175.00 0.17 0.42 0.17 2.61metal in 100% sulphide B 36.50 17743.06 17.24 42.58 17.24 264.63
Pd Au Cu S/Se Cu/Ni Pd/Pt Pd/IrUnit ppb ppb ppm
Layered (n=8) 15.32 5.08 116.00 2746 0.61 0.96 21.3metal in 100% sulphide 9321.69 3090.33 70566.67Inclusion-bearing (n=6) 412.16 6.57 47.00 2506 1.18 4.16 143.1metal in 100% sulphide 752192.00 11990.25 85775.00Breccia (n=9) 1865.69 109.30 1231.00 1564 3.83 2.81 134.4metal in 100% sulphide 206356.62 12089.24 136156.06Boundary (n=1) 214.00 18.50 476.00 2508 5.06 3.13 146.6metal in 100% sulphide 52073.33 4501.67 115826.67Footwall Breccia (n=1) 4.87 1.71 95.60 14726 0.78 1.38 25.6metal in 100% sulphide 413.38 145.15 8114.88Footwall (n=3) 3.06 0.36 72.00 16077 0.41 1.17 18.0metal in 100% sulphide 310.25 36.50 7300.00
Table 6-3. A: Average whole-rock chalcophile element concentrations for core samples
from drill hole RV00-22 and some important average ratios. B: Concentrations in the
same samples (n = number of samples), recalculated to metal 100% sulphide. See
Appendix 1 for complete data listing.
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An additional 13 “fill-in” samples were subsequently collected and analyzed for Pt, Pd,
Au, Cu, Ni, S and Se at the Geoscience Laboratories in Sudbury; these samples are also
used in the 28 sample set of Group-2. Group-1 data provides a detailed
chemostratigraphic section, in terms of Pt, Pd, Au, Cu, Ni, S and Se, through the
stratigraphy of the Marginal Series rocks (LU to FBX) and into the FW. The second data
set, referred to as Group-2, consists of 28 samples, mainly derived from the original core
pulp samples but also comprising an additional 13 samples from original drill core (also
used in the Group-1 data set), analyzed for PGE (Ir, Ru, Rh, Pd, Pt, Au), and whole-rock
major, trace and rare-earth elements at the Geoscience Laboratories; complete listings of
these data are in Appendix 3. Group-2 data provides more detailed information in terms
of the geochemical variation through the Marginal Series rocks (LU to FBX) rocks.
A total of 21 thin sections from Group-1 were examined in detail and petrographic
descriptions for these samples are provided in Appendix 2. Layered Unit samples (3
samples) comprise medium-grained gabbronorite with relict granular-idiomorphic and
granular-hypidiomorphic textures (Photo 6-9b). Inclusion-bearing Unit samples (2
samples) comprise medium-grained leucogabbro with relict granular-idiomorphic
textures. The 13 samples from the Breccia Unit are dominated by medium-grained
gabbro and subordinate melagabbro with relict granular-idiomorphic and granular-
hypidiomorphic textures (Photo 6-8). Of these 13 samples, 8 have well preserved
igneous textures but 5 samples, which are finer grained, are extensively recrystallized.
Relict igneous textures consist of actinolite and blue-green hornblende pseudomorphing
pyroxene, tremolite after olivine (rare), and plagioclase, replaced in varying degrees, by
sericite, amphibole and saussurite.
All samples possess mineral assemblages (chlorite-actinolite/tremolite) typical of
greenschist facies metamorphism along with evidence for secondary, low-temperature
(hydrothermal) alteration (i.e. saussuritization, secondary quartz, Photo 6-6b). Sulphides
(chalcopyrite > pyrrhotite > pentlandite > pyrite) with magmatic textures (mainly
disseminated and interstitial, Photo 6-8a) are atypical and most sulphides occur as very
fine-grained patches associated with fine- to medium-grained patches of saussuritization
which is within or adjacent to plagioclase grains; these sulphide patches commonly
comprise biotite, blue-green hornblende and epidote.
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Photo 6-6. Core from diamond drill hole RV00-22. (A) Footwall (RV22-03; 2.1 ppb Pd, 1.7 ppb Pt, 60 ppm Cu, 133 ppm Ni): Fine-grained migmatite with felsic leucosome (cream-white-yellow) and mafic melanosome with several percent disseminated sulphide (ds) and blue quartz (bq); pyrite is dominant with subordinate chalcopyrite and pyrrhotite. (B) Boundary Unit (29756; 214 ppb Pd, 68 ppb Pt, 476 ppm Cu, 94 ppm Ni): Fine- to medium-grained CIPW gabbronorite with saussuritized and epidotized plagioclase grains (a-plag) and fine-grained blue quartz. The Canadian one cent piece is about 1.8 cm in diameter.
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Photo 6-7. Core from diamond drill hole RV00-22. (A) Breccia Unit (29753; 1102 ppb Pd, 347 ppb Pt, 348 ppm Cu, 341 ppm Ni): CIPW olivine gabbronorite with several % finely disseminated sulphide (chalcopyrite-pyrrhotite) and distinct blue quartz; the latter is often associated with higher PGE grades. (B) Breccia Unit (29733; 872 ppb Pd, 324 ppb Pt, 1130 ppm Cu, 328 ppm Ni): CIPW quartz normative gabbro with several % disseminated sulphide (ds) and a distinct patch of altered cream-white feldspar and blue-grey quartz (bq). The Canadian one cent piece is about 1.8 cm in diameter.
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Photo 6-8. Core from drill hole RV00-22. (A) Breccia Unit (29707; 1733 ppb Pd, 718 ppb Pt, 2700 ppm Cu, 615 ppm Ni): Medium-grained gabbro with interstitial sulphide (is), disseminated sulphide (ds), and veinlets of remobilized sulphide (vs); chalcopyrite and pyrrhotite are the dominant sulphides. (B) Breccia Unit (29702; 6670 ppb Pd, 2375 ppb Pt, 3600 ppm Cu, 532 ppm Ni): Medium-grained gabbro with disseminated sulphide (ds) and fine-grained blue-grey quartz. The Canadian one cent piece is about 1.8 cm in diameter.
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Photo 6-9. Core from drill hole RV00-22. (A) Inclusion-bearing Unit (29645; 1864 ppb Pd, 169 ppb Pt, 41 ppm Cu, 44 ppm Ni): Coarser grained gabbroic autolith in medium-grained mafic matrix with trace disseminated sulphide (ds). (B) Layered Unit (22692; 21 ppb Pd, 21 ppb Pt, 117 ppm Cu, 116 ppm Ni): Medium-grained CIPW olivine gabbronorite with minor disseminated sulphide (ds) and relict igneous textures - pyroxene is pseudomorphed by actinolite and blue-green hornblende and plagioclase is replaced in varying degrees by sericite, amphibole (uralite) and saussurite. The Canadian one cent piece is about 1.8 cm in diameter.
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Fine-grained disseminated chalcopyrite, pyrrhotite and pyrite can occur with tremolite,
which occurs as pseudomorphs after olivine and/or orthopyroxene.
6.6.1 General Geochemistry
Whole-rock major, trace, rare-earth element, and PGE data for selected samples from
Group-2 (28 samples) data are presented in Table 6-4; a compete listing of the Group-2
data is provided in Appendix 3. All of the samples from the intrusion, with the exception
of sample 29753 from the BX, classify as sub-alkaline rocks (Miyashiro, 1978). CIPW
normative calculations were completed on 25 of the 28 samples and a summary of these
results for selected samples are provided in Table 6-5; rock types were determined on the
basis of the weight percent normative minerals. All eight samples from the LU are
olivine-normative with seven samples classifying as olivine leucogabbronorite and one
sample (29612) classifying as gabbronorite. All six samples from the IBZ are olivine-
normative with three samples classifying as olivine leucogabbronorite and the other three
classifying as leucogabbronorite. Nine of the ten samples from the BX are olivine-
normative with only one sample (29733), a gabbro, being quartz-normative (quartz
oversaturated). Five of the samples are classified as gabbronorite, two as
leucogabbronorite, one as olivine leucogabbronorite and one as olivine gabbronorite.
The single FBX sample is olivine-normative and are classified as leucogabbronorite with
a low (0.18) calculated corundum content, due to an increase in aluminium which could
be a result of interaction with the footwall paragneiss.
Rock compositions from the Breccia Unit typically display the widest variation due
to extreme irregularity in the proportions of fragments and matrix. Estimating the
proportion of fragments and matrix in drill core is also problematic due to a lack of
obvious contacts between fragments and the hosting matrix and in many instances it is
difficult to discern the fragments from the matrix.
6.6.2 Major Element Variations
Selected major elements for samples from Group-2 are plotted against stratigraphic
height (drill hole depth) in Figure 6-6. Silica concentrations range from 45.26 to 51.09
wt% SiO2 in the intrusion, and samples from the FW, FBX and BZ show the highest
overall wt% SiO2.
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Sample 22692 29635 29645 29683 29702 29753 29756 29762 RV22-03From (m) 2.5 77 92.5 160 181 224.7 229 236.5 255.78
Unit LU LU IBZ IBZ BX BX BZ FBX FWSiO2 48.62 45.26 49.64 51.09 48.81 45.79 51.18 50.59 55.70TiO2 0.47 0.68 0.39 0.14 0.14 0.27 0.34 0.71 0.37Al2O3 16.84 13.58 22.73 21.85 20.48 16.40 15.79 18.00 19.38
Fe2O3* 12.11 15.56 6.85 5.52 8.70 11.43 11.28 10.40 7.25MnO 0.17 0.21 0.10 0.10 0.12 0.18 0.17 0.13 0.08MgO 8.74 11.01 4.52 5.63 5.98 10.54 8.06 7.21 4.97CaO 9.32 8.40 10.90 10.99 9.67 7.89 9.98 6.18 4.44Na2O 2.24 1.49 3.21 2.90 2.70 2.36 2.10 3.22 4.64K2O 0.63 0.79 0.87 0.80 0.79 0.89 1.00 1.34 1.14P2O5 0.06 0.06 0.05 0.01 0.01 0.03 0.01 0.06 0.05
S 0.06 0.08 0.03 0.01 0.78 0.34 0.15 0.43 0.26Total 101.0 99.4 100.5 100.4 98.9 98.6 100.9 100.2 100.3Mg# 62.68 62.22 60.56 70.36 61.53 68.21 62.45 61.74 61.47
Pt 21.4 9.76 168.6 60.6 2375 347 68.3 3.53 1.71Pd 20.9 12.02 1864 125.5 6670 1102 214 4.87 2.12Ni 116 158 44 19 532 341 94 123 133Cu 117 134 40.5 48.9 3600 348 476 95.6 60La 7.46 6.86 5.61 1.76 2.27 6.09 3.13 17.41 38.80Ce 15.47 14.47 11.73 3.54 4.62 12.04 6.31 29.69 65.62Pr 1.95 1.85 1.47 0.45 0.58 1.44 0.83 3.28 6.57Nd 7.85 7.34 5.71 1.81 2.31 5.90 3.55 11.30 21.86Zr 39.89 48.02 34.60 13.71 9.56 15.30 11.62 30.55 55.50Sm 1.82 1.75 1.28 0.42 0.54 1.26 0.98 1.60 2.60Eu 0.70 0.67 0.64 0.32 0.50 0.70 0.57 1.74 2.30Gd 1.96 1.91 1.40 0.49 0.60 1.31 1.15 1.18 1.88Tb 0.34 0.33 0.24 0.09 0.11 0.21 0.20 0.16 0.21Dy 2.14 2.06 1.48 0.61 0.68 1.32 1.25 0.90 1.06Y 12.97 11.92 8.65 3.48 4.00 7.87 7.79 5.64 6.09
Ho 0.49 0.46 0.33 0.14 0.15 0.28 0.30 0.20 0.22Er 1.39 1.26 0.91 0.36 0.44 0.84 0.86 0.63 0.71Tm 0.21 0.21 0.14 0.06 0.07 0.14 0.14 0.10 0.13Yb 1.37 1.23 0.91 0.38 0.43 0.95 0.88 0.76 0.84Lu 0.22 0.21 0.15 0.06 0.07 0.16 0.15 0.14 0.15
∑REE 44 41 32 11 13 33 21 70 143(Th/Yb)N 5.46 6.27 5.99 9.46 2.83 3.48 3.16 8.55 15.74(Nb/Th)N 0.19 0.20 0.25 0.15 0.18 0.17 0.09 0.14 0.09
Zr/Sm 21.92 27.44 27.03 32.64 17.70 12.14 11.86 19.09 21.35Nb/Ta 13.87 14.80 13.13 5.07 2.13 3.64 2.53 8.73 4.39
Table 6-4. Geochemical data (Group-2) from drill hole RV00-22, Dana North Deposit, River Valley intrusion. Fe2O3*=total iron; SiO2 to Total=wt%; Pt, Pd=ppb; Ni to Lu=ppm; N=primitive mantle-normalized
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Sample 22692 22696 29601 29607 29612 29618 29622 29635 29645 29662 29670Rock Type OGN OGN OGN OGN GN OGN OGN OGN OLGN LGN OLGN
Unit LU LU LU LU LU LU LU LU IBZ IBZ IBZNorm Minerals
quartzplagioclase 53.91 53.50 56.67 55.81 58.01 47.03 57.45 42.44 73.12 65.43 66.27orthoclase 3.78 3.60 3.60 3.31 4.14 3.13 3.90 4.85 5.20 4.37 2.54corundumdiopside 9.54 8.77 6.71 9.31 8.72 12.07 8.64 11.19 7.03 8.75 5.28
hypersthene 18.03 19.15 16.58 16.50 17.67 19.16 16.81 17.65 0.53 11.42 10.53olivine 10.91 11.35 12.58 11.41 7.90 14.53 9.50 18.85 11.70 7.65 13.32ilmenite 0.91 0.74 0.82 0.89 0.85 0.80 0.84 1.35 0.74 0.49 0.21
magnetite 2.49 2.52 2.52 2.42 2.23 3.00 2.38 3.29 1.41 1.55 1.70apatite 0.14 0.12 0.14 0.12 0.14 0.05 0.09 0.14 0.12 0.07 0.02zircon 0.01 0.01 0.01
chromitepyrite 0.13 0.06 0.13 0.08 0.15 0.11 0.19 0.17 0.06 0.04 0.02calcite 0.16 0.23 0.27 0.16 0.23 0.16 0.25 0.09 0.14 0.25 0.14
*Total: 100.01 100.04 100.02 100.02 100.04 100.04 100.05 100.03 100.05 100.02 100.03
Sample 29683 29689 29696 29702 29707 29717 29721 29733 29744 29756 29762Rock Type LGN GN GN LGN GN GN LGN G OLGN GN LGN
Unit IBZ BX BX BX BX BX BX BX BX BX FBXNorm Minerals
quartz 3.34plagioclase 69.73 52.45 39.35 65.97 55.10 51.10 62.23 32.83 62.15 48.91 59.01orthoclase 4.79 1.77 3.37 4.79 2.25 2.84 2.72 4.37 3.49 5.97 8.16corundum 0.18diopside 8.19 16.09 14.53 5.41 13.34 10.97 9.21 13.02 9.45 15.38
hypersthene 11.08 18.65 35.24 12.85 21.52 30.54 18.46 41.80 10.37 24.64 21.19olivine 4.65 8.73 3.52 7.24 3.59 1.63 5.19 12.14 1.76 6.81ilmenite 0.27 0.25 0.46 0.27 0.36 0.32 0.30 0.55 0.42 0.65 1.39
magnetite 1.13 1.88 2.78 1.81 2.09 2.16 1.65 2.93 1.78 2.31 2.16apatite 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.05 0.02 0.02 0.14zircon
chromitepyrite 0.02 0.08 0.64 1.70 1.70 0.38 0.11 1.04 0.02 0.32 0.93calcite 0.14 0.09 0.16 0.05 0.14 0.09 0.16 0.11 0.20 0.09 0.07
*Total: 100.02 100.01 100.07 100.11 100.11 100.05 100.05 100.04 100.04 100.05 100.04
Table 6-5. CIPW normative calculations for samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion. CIPW minerals normalized to 100%; rock names based on weight % normative minerals; OGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite; OLGN=olivine leucogabbronorite; LG=leucogabbro
353
0
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100
125
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175
200
225
250
2750 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
TiO2 (wt%)
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBXBZ
Figure 6-6a. Variation in wt% TiO2 with drill hole depth (metres) from drill hole RV00-
22, Dana North Deposit, River Valley intrusion.
354
0
25
50
75
100
125
150
175
200
225
250
2750 2 4 6 8 10 12
MgO (wt%)
Dril
l Hol
e D
epth
(m)
14
LU
IBZ
BX
FW
FBXBZ
Figure 6-6b. Variation in wt% MgO with drill hole depth (metres) from drill hole RV00-
22, Dana North Deposit, River Valley intrusion.
355
There is a slight overall decrease through the anomalous BX, a further decrease through
the IBZ and a still further decrease into the lower LU; silica contents show a gradual
increase upward through the LU. The relative rise in SiO2 values in the BX corresponds
well with the highest Pt+Pd concentrations in this unit, suggesting a relationship between
increased silica content and higher grade PGE. This supports observations that higher
grades of PGE tend to be associated with patches of blue-grey quartz.
The concentration of TiO2 is primarily controlled by the abundance of Fe-Ti oxide
minerals, primarily titanomagnetite, and by fractionation whereby TiO2 behaves
incompatibly. The TiO2 concentration ranges from 0.11 to 0.68 wt% TiO2 in the
intrusion and are highest in the LU, FBX and FW. In the BX, TiO2 is the lowest,
averaging 0.20 wt% and in the overlying IBZ, TiO2 is slightly higher averaging 0.23
wt%; the lowest single value of 0.11 wt% TiO2 comes from the lower IBZ. A maximum
of 0.68 wt% TiO2 is reached just above the contact between the LU and IBZ, followed by
a drop in TiO2 concentrations to an average 0.43 wt% for the remainder of the LU
samples. In the BX itself, the highest TiO2 concentration of 0.28 wt% is coincident with
the only quartz-normative sample (29733). In drill core, this 0.70 m long sample section
contains a high proportion (~10%) of blue quartz which occurs with about 2% finely
disseminated sulphide (Photo 6-7). This association between relatively high SiO2 and
TiO2 whole-rock concentrations suggests that the blue to blue-grey quartz colouration is
due impurities of titanium in the quartz. Ma et al. (2001) presented data which indicated
that sub-micrometre inclusions of ilmenite are a common cause of the blue colour in
quartz.
Concentrations of Fe2O3* range from 5.52 to 15.56 wt% Fe2O3* with the highest
average values (12.54 wt%) occurring in the LU where the samples define a gradual up-
section decrease in Fe2O3*. As with peak TiO2 concentrations, a maximum of 15.56 wt%
Fe2O3* is reached just above the contact between the LU and IBZ, followed by a drop in
Fe2O3* concentrations for the remainder of the LU samples. The concentration of Fe2O3*
is elevated in the BX (average = 10.40 wt%) relative to the IBZ (average = 6.79 wt%)
with values in the BX approaching those in the LU (average = 12.54 wt%). In the BX
itself, and as seen with TiO2, the highest concentration of 13.99 wt% Fe2O3* is coincident
with the only quartz-normative sample (29733).
356
The Mg-number ranges from 0.61 to 0.73 in the intrusion, averaging 0.62 in the LU,
and averaging 0.67 in both the IBZ and BX; the average Mg-number from the LU is the
same as the individual Mg-numbers of the BZ and FBX and the average Mg-number of
the FW. The higher Mg-numbers in the IBZ and BX reflects the primitive (mafic) nature
of the fragments that occur within these units, particularly in the BX where all the
fragments contain >12 wt% MgO (see Section 6.7). Reflecting the high Mg
compositions of the BX fragments, the Mg-number shows an overall increase through the
BX, followed by a relatively sharp decline through the IBZ, and finally a gradual overall
increase in the LU; the increase in Mg-number through the LU is more than likely the
result of fractionation of titanomagnetite and magnetite, which may be what is reflected
in the increased TiO2 and Fe2O3 concentrations in the lower part of the LU.
Compositions of MgO range from as low as 4.3 wt% in the upper part of the IBZ to
11.8 wt% in the BX, with the highest average concentrations occurring in the BX (~9.3
wt% MgO) and LU (~8.9 wt% MgO). Core samples from the LU have the highest CIPW
olivine-normative values (average 12.1% normative olivine) which is reflected in the
high MgO concentrations. Concentrations of MgO mirror those of Fe2O3*, exhibiting the
greatest variation through the BX, and reflecting the variability in the proportion of
fragments to matrix within each of the drill core sample sections; higher MgO and Fe2O3
values are probably a consequence of higher proportions of fragments relative to matrix
(see Section 6.7).
Concentrations of Al2O3 range from 10.95 wt% in the lower BX to 23.49 wt% in the
upper IBZ, share very similar averages in the BX (16.49 wt%) and LU (16.61 wt%) and
is consistently higher in the IBZ where it averages 21.74 wt%. These higher aluminium
contents are reflective of the leucocratic nature of the rocks in the IBZ.
6.6.3 Trace and Rare-Earth Element Variations
Selected trace elements for samples from Group-2 are plotted against stratigraphic
height (drill hole depth) in Figure 6-7. A summary of the principal trace and rare-earth
element abundances and ratios from of the units is provided in Table 6-6. Relative
abundances of the incompatible trace elements Zr, Y, Nb and La are primarily governed
by the proportions of primocrysts (solid) to interstitial components (liquid) in the sample
and their relative amount of differentiation (Vogel et al., 1999).
357
Unit N Eu/Eu* (La/Sm)N (La/Yb)N (La/Yb)N ∑REERange Range Average Range Range ppm
Layered 8 1.094-1.258 2.97-4.38 3.58 2.58-4.06 24-43Inclusion-bearing 6 1.418-2.502 3.16-4.38 3.40 2.30-4.24 6-32
Breccia 9 1.095-2.669 2.88-4.83 2.88 1.53-4.36 7-24Boundary 1 - - 2.42 - -
Footwall Breccia 1 - - 15.60 - -Footwall 3 2.981-4.073 10.67-14.92 20.31 13.27-31.45 83-143
Table 6-6. Principal features of trace and REE abundances and ratios for each of the units
intersected in drill hole RV00-22, River Valley intrusion. N=number of samples in the
average or range. The value Eu/Eu*= EuN/√[(SmN).(GdN)] was calculated using
Geometric Mean method of Taylor and McLennan (1985) where “N” indicates chondrite
normalized.
358
0
25
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75
100
125
150
175
200
225
250
2750 10 20 30 40 50
Zr (ppm)
Dril
l Hol
e D
epth
(m)
60
LU
IBZ
BX
FW
FBXBZ
Figure 6-7a. Variation in whole-rock Zr (ppm) against drill hole depth (metres) from drill
hole RV00-22, Dana North Deposit, River Valley intrusion.
359
0
25
50
75
100
125
150
175
200
225
250
2750 2 4 6 8 10
(Th/Nb)N
Dril
l Hol
e D
epth
(m)
12
LU
IBZ
BX
FW
FBXBZ
Figure 6-7b. Variation in primitive mantle-normalized (Th/Nb)N against drill hole depth
(metres) from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
360
The highest average incompatible trace element abundances occur in the LU (Zr = 32, Y
= 11.33, Nb = 1.7, La = 6.23), reflecting the evolved nature of these rocks, whereas the
lowest average abundances occur in the BX (Zr = 9, Y = 5.39, Nb = 0.5, La = 2.87),
reflecting the primitive (high MgO) nature of these rocks. Upward increasing
concentrations in Y and Nb through the IBZ are indicative of normal fractionation.
Although trace element values in the BX are highly variable, they do define a general up-
section decrease in all of these trace elements. This variability and overall decrease could
reflect the influx of new magma(s) and/or subsequent mixing with resident magma and
rocks. There is a general upward increase in (Th/Yb)N with the greatest variation in the
BX. Values of (Th/Yb)N for samples from the BX, IBZ and LU range from about 2 to 10
times that of primitive mantle (primitive mantle Th/Yb ~0.17; McDonough and Sun,
1995) suggesting that these rocks have been crustally contaminated.
Europium is relatively abundant compared to other REE in plagioclase and Eu
anomalies (positive or negative) can be used as a measure of plagioclase fractionation in
a magma. Values of Eu/Eu* are calculated using the geometric mean method of Taylor
and McLennan (1985) whereby calculated Eu/Eu* values >1 are considered positive and
those <1 are considered negative Eu/Eu* anomalies; for simplicity Eu/Eu* anomalies are
referred to as Eu anomalies. The Eu/Eu* values show a gradual decrease with
stratigraphic height through the IBZ and LU with the Eu anomalies becoming less
pronounced upward through the LU. This gradual decrease likely reflects the removal of
plagioclase from the melt through crystal fractionation.
The ratio of (La/Sm)N (normalized to primitive mantle) can provide a good
indication as to whether or not magma has interacted with crustal rocks; higher ratios
suggests increased crustal assimilation. In the plot of (La/Sm)N, the highest values are
within the FBX ((La/Sm)N = 7.03) and FW (average (La/Sm)N = 8.07); these values are
representative of the country rock (FW) and region of mixing/assimilation (FBX). The
one BZ ((La/Sm)N = 2.06) value is slightly lower than the overlying BX (average
(La/Sm)N = 2.55) and the IBZ (average (La/Sm)N = 2.62) is only slightly higher than the
BX and LU (average (La/Sm)N = 2.52). The consistently low (La/Sm)N values through
the BX and IBZ and their similarity with the overlying LU suggests that there was very
little assimilation of local country rock. If local crustal contamination would have played
361
an essential role, then one would expect that values in the BX and BZ would have been
closer to those for the FBX and FW components. This lack of a local contamination
signature in the BX and in the other units of the Marginal Series rocks is an indication
that chemical contamination from local footwall rocks was not a major factor on
mineralization. However, assimilation of crust appears to have driven the magma to S-
saturation and the formation of sulphides in a deep-seated staging magma chamber, as
suggested for the East Bull Lake intrusion (James et al., 2002a).
Chondrite-normalized REE patterns for rocks from the River Valley intrusion are
illustrated in Figure 6-8 and some of the more important features of these plots are
summarized in Table 6-6. All River Valley intrusion rocks have patterns of LREE
enrichment and a narrow range in (La/Yb)N values from 2.42 to 3.58; La/Yb ratios are
used to demonstrate the relative abundance and extent of fractionation of the LREE from
the HREE. Vogel et al. (1999) reported similar REE patterns and a narrow range in
(La/Yb)N (2.0-6.5) from the Agnew Lake intrusion. The greatest range in (La/Yb)N
values are from the IBZ and BX, reflecting the variability in rock types within these
units. All individual samples from the River Valley intrusion units (LU, IBZ, BX and
BZ) have strong positive Eu anomalies with absolute Eu/Eu* values ranging from 1.09 to
2.67, with the highest average value from the IBZ (1.81); the FBX and FW samples have
strong Eu/Eu* values of 3.85 and 3.40, respectively (Table 6-6). The average ∑REE is
highest in the footwall rocks (105 ppm), gradually decreasing through the FBX (69 ppm)
and BZ (20 ppm). Average ∑REE are lowest in the BX (17 ppm) and IBZ (17 ppm) and
are elevated in the LU (37), increasing upward through the LU. The gradual increase in
∑REE with stratigraphic height and a concomitant decrease in the positive Eu/Eu*
anomalies are consistent with closed-system magmatic differentiation dominated by
plagioclase fractionation.
Individual samples from units in the River Valley intrusion show very similar REE
patterns that generally parallel one another (Fig. 6-8).
362
Figure 6-8. Chondrite-normalized rare-earth element plots for average samples from drill
hole RV00-22, Dana North Deposit, River Valley intrusion. “RVI – Parent Magma” may
represent the parental magma composition for the River Valley intrusion (James et al.,
2002a). Data for “Matachewan Dike” is from Easton and Hrominchuk (1999), and data
for “EBLI – Lower Series” and “EBLI – Parent Magma” (estimate of East Bull Lake
intrusion parental magma composition) are from the East Bull Lake intrusion (Peck et al.,
1995). Normalizing values are from Lodders and Fegley (1998).
363
Slight variations in the REE slope between individual samples, approximated by the
(La/Yb)N ratio (Table 6-6), can be attributed to modal differences whereby samples with
lower La/Yb values have higher relative mafic mineral to plagioclase contents and vice
versa, which is consistent with known REE partitioning in minerals (Henderson, 1984).
Heavy REE and LREE patterns in the LU, IBZ and BX range from about 6-30, 1.5-24
and 2-26 times chondrite, respectively. Footwall rocks and FBX show the highest
enrichment in LREE and the IBZ and BX show the lowest LREE and HREE enrichment
patterns. Average chondrite-normalized patterns from the LU, IBZ, BX and BZ bracket
the pattern for an average of nine samples from the East Bull Lake Lower Series (Fig. 6–
10a).
James et al. (2002a) described samples of boninite-like rocks from the River Valley
and East Bull Lake intrusions, and suggested that these may represent boninitic parent
magma compositions for the East Bull Lake suite intrusions. Of particular note is sample
H292 (Fig. 6-10, “RVI Parent Magma”) which is a fine-grained orthopyroxene-phyric
norite from the Marginal Zone in the River Valley intrusion (Dana Township). This
sample exhibits a flat (~10 x chondrite) to very slightly U-shaped REE pattern and has
relatively high SiO2 (51.2 wt%), Al2O3 (13.1 wt%) and MgO (11.5 wt%; Mg-number =
68), and low TiO2 (0.33 wt%) and alkalis (Na2O+K2O = 0.73 wt%); Easton (2003) also
reported data from the same lithology (sample 99RME-2291).
Primitive mantle-normalized multi-element plots for average concentrations in the
River Valley intrusion units and the BX are shown in Figure 6-9. The patterns are sub-
parallel and show the same relative arrangement between units as in the REE patterns in
Figure 6-8. All of the average primitive mantle-normalized patterns for River Valley
intrusion rocks and all but one of the individual samples (LU 29635) show pronounced
positive Sr anomalies which correlate with high modal plagioclase. Of particular
importance in multi-element patterns are negative high field strength element (HFSE)
anomalies (i.e. Nb, Ta and P); Ti shows subtle positive and negative anomalies. The
average patterns from the LU, IBZ and BX have strong negative Nb, Ta and P anomalies
(relative to the LREE) and weak negative Ti anomalies which, along with LREE-
enrichment trends, are characteristics of magma which has interacted with a crustal
reservoir (Lightfoot and Naldrett, 1996).
364
Figure 6-9. Primitive mantle-normalized multi-element diagrams for samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion. (A) Averages from various units of the River Valley intrusion and footwall rocks. (B) Average compositions of River Valley rocks compared with individual Breccia Unit (BX) compositions. Normalizing values are from McDonough and Sun (1995).
365
The pattern for the BZ also shows negative Nb+Ta and P anomalies but a positive Ti
anomaly and although the majority of individual samples from the LU, IBZ and BX are
dominated by negative Nb+Ta, P and Ti anomalies (all samples have negative P
anomalies), there are a few samples from each of these units that display flat to slightly
positive Nb+Ta and/or Ti anomalies (Fig. 6-9). While the majority of REE patterns
exhibit negative Nb and Ta anomalies, it is important to note that, as in the patterns from
Nipissing Gabbro suite rocks, the negative Nb anomalies are much larger than those of
Ta; this is a characteristic of boninitic magmas (Foley et al., 2002).
6.6.4 Chalcophile (PGE, Cu, Ni) Element Variations
Contact-type, PGE-bearing sulphide mineralization, occurring at or near the
preserved igneous contact of the River Valley intrusion within the Marginal Series,
consists primarily of chalcopyrite-dominated disseminated sulphide and locally coarse-
grained blebby sulphide. Similar sulphide occurrences have been described in the East
Bull Lake intrusion by Peck et al. (1993a, 1995) and James et al. (2002a), and in the
Agnew Lake intrusion by Vogel et al. (1998a, 1999). A summary of the average
chalcophile metals plus Au, along with important metal ratios for core from drill hole
RV00-22 is provided in Table 6-7. The highest average concentration of Pt+Pd is from
the BX (2271 ppb Pt+Pd) which is consistent with the region of highest visible sulphide.
This unit also show the highest average Pd/Pt (2.7) and Cu/Ni (5.1) and the lowest
average S/Se value (1800). All of the unmineralized (≤0.05 wt% S) samples have high
average Pt+Pd, relative to common mafic magmas (e.g. Crocket, 1981, 2002; Hamlyn et
al., 1985; Keays, 1995) and the BX shows the highest average Pd/Pt (2.0) and Cu/Ni (3.5)
values and the lowest average S/Se value (1578). These ratios contrast sharply with
average values from the South Roby Zone (Lac des Iles intrusion), which has a much
higher Pd/Pt (8.7) value and a lower Cu/Ni (1.0) value (based on 51 samples; J. Hinchey,
unpublished data, 2004), and whose sulphide mineralization has a hydrothermal affinity
(Brügmann et al., 1989).
It is well established that the PGE have extremely high Nernst sulphide-silicate
partition coefficients and are sensitive indicators of sulphide ore-forming processes
(Peach et al., 1990; Peach et al., 1994). In addition, their abundance and distribution
provides a measure of the degree of S-saturation or S-undersaturation of the magma from
366
which the rock crystallized (Hamlyn and Keays, 1986; Keays, 1995; Vogel and Keays,
1997). During the fractionation of S-undersaturated mafic magmas, incompatible
elements such as Cu, S, Se, Pd and Pt become concentrated in the residual silicate melt,
whereas compatible elements such as Ni, Ir, Ru and Os are removed with the early
precipitation of silicate and/or oxide phases (Keays, 1995). Once S-saturation of the
magma is achieved, immiscible magmatic sulphides form and the magma becomes
rapidly depleted in PGE relative to other siderophile and chalcophile elements (i.e. Cu, S
and Se) because of the PGE’s very high affinity for sulphide melt. The ratioing of the
PGE against themselves (i.e. IPGE - Os, Ir, Ru versus PPGE – Rh, Pt, Pd) and against
elements such as Cu, S and Se are therefore widely accepted as useful discriminators in
considering the origin of PGE in mafic rocks (e.g. Peck et al., 1993a, 1993b; Keays,
1995; Seitz and Keays, 1997; James et al., 2002a, 2002b) and in the exploration for PGE
deposits (e.g. Hoatson and Keays, 1989; Reeves and Keays, 1995; Maier et al., 1998).
For example, Hoatson and Keays (1989) used ratios and abundances of PGE from surface
transects across the Munni Munni layered intrusion (Australia) to establish the
stratigraphic level at which reef-type PGE mineralization is concentrated. Subsequent
diamond drilling (ca. 1990) led to the definition of a 1-5 m thick layer of disseminated
PGE-rich sulphides (Barnes et al., 1990, 1992) at the approximate level indicated by
Hoatson and Keays (1989) and demonstrated the practical use of PGE and other
chalcophile elements as a robust technique in mineral exploration.
Selected bivariate plots of the chalcophile element concentrations from the variably
mineralized Group-1 data are provided in Figure 6-10 and Group-2 data in Figure 6-11.
In general, correlations between the chalcophile elements are strongest in the samples
from the mineralized BX, indicating that the PGE in the BX are strongly sulphide
controlled. Correlations between Pt and Pd, Cu and S, and Cu and Se from all units of
the River Valley intrusion are very strong. However, correlations between Cu and Ni, Cu
and Pd, Cu and Pt, Ni and Pd, S and Pt, and S and Pd are all very good in only the BX
and are relatively poor with respect to samples from the LU and IBZ. Nonetheless, the
generally positive correlations between the chalcophile metals in the BX and to a lesser
extent in the LU and IBZ, suggests that PGE distribution in the River Valley intrusion is
strongly controlled by sulphide.
367
Unit N *Au *Pt *Pd *3E *Pt+Pd *Ni *CuAll Samples ppb ppb ppb ppb ppb ppm ppm
Layered 27 8 33 20 61 53 131 457Inclusion-bearing 20 11 90 122 223 212 47 63
Breccia 55 110 573 1697 2380 2271 256 1317Boundary 4 16 55 126 197 181 145 217
Footwall Breccia 3 15 14 16 44 30 138 82Footwall 3 0 3 3 6 6 175 72
N *Au *Pt *Pd *3E *Pt+Pd *Ni *Cuunmineralized** ppb ppb ppb ppb ppb ppm ppm
Layered 12 8 33 21 63 54 116 90Inclusion-bearing 19 11 93 127 232 221 46 61
Breccia 9 26 121 278 425 399 81 191
Unit Se S S/Se Pd/Pt Cu/Ni Cu/PdAll Samples ppb wt%
Layered 218 0.14 6385 0.6 3.5 22328Inclusion-bearing 87 0.02 2648 1.4 1.3 514
Breccia 1942 0.34 1772 3.0 5.1 776Boundary 408 0.28 6928 2.3 1.5 1725
Footwall Breccia 262 0.37 14140 1.2 0.6 5127Footwall 226 0.36 16077 1.2 0.4 23664
Se S S/Se Pd/Pt Cu/Ni Cu/Pdunmineralized** ppb wt%
Layered 140 0.04 3164 0.6 0.8 4260Inclusion-bearing 81 0.02 2601 1.4 1.3 482
Breccia 195 0.03 1569 2.3 2.4 685
Table 6-7. Summary of average chalcophile metals plus Au, along with important metal
ratios for core from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
*assays from XRAL Laboratories (PFN); **unmineralized = <0.05 wt% S; Values for 3E
= Pt+Pd+Au; All other assays from Geoscience Laboratories in Sudbury.
368
1
10
100
1000
10000
10 100 1000 10000
Cu (ppm)
Pd (p
pb)
Layered UnitInclusion-Bearing UnitBreccia UnitBoundary Zone UnitFootwall Breccia UnitFootwall
1
10
100
1000
10000
10 100 1000 10000
Cu (ppm)
Pt (p
pb)
Layered UnitInclusion-Bearing UnitBreccia UnitBoundary Zone UnitFootwall Breccia UnitFootwall
Figure 6-10. Bivariate scatter plots of chalcophile metal abundances in mineralized and unmineralized samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
369
0.1
1
10
100
1 10 100 1000 10000
Pd (ppb)
Ir (p
pb)
LUIBZBXBZFBXFW
Group-2 Data
(C)
1
10
100
1000
1 10 100 1000 10000
Pd (ppb)
Pd/Ir
LUIBZBXBZFBXFW
Group-2 Data
(C)
Figure 6-11. Bivariate scatter plots of Group-2 data from drill hole RV00-22. (A) Pd versus Ir and (B) Pd versus Pd/Ir show the moderate to excellent correlation between Pd and Ir, supporting the interpretation that these sulphides are magmatic; some higher Pd/Ir values are probably due to localized hydrothermal redistribution of the sulphide.
370
The poor correlation between the chalcophile elements in the LU and IBZ may be
explained in terms of their wide variation in Pd concentration (Peck et al., 2001). The
moderate to excellent correlation between Pd and Ir in Figure 6-11 clearly supports a
magmatic sulphide controlled origin for the mineralization.
The increase in the Pd/Ir ratio, which increases as Pd increase, is due to the higher
Nernst partition coefficient of Pd (DPd ~35,000; Peach et al., 1990) relative to Ir (DIr
~17,000; Peach et al., 1990) and will increase as a magma becomes more evolved. This
explains the strong enrichment of Pd relative to Ir in some of the BX and IBZ samples
and it is probable that some of these higher values are due to localized remobilization of
the sulphide, related to deuteric and/or hydrothermal (overprint) upgrade of the sulphide.
Figure 6-12 is a plot of Se and Pd data for unmineralized rocks from Group-1 that
have <0.05 wt% S. This plot is useful for discriminating between rocks that formed from
S-undersaturated second-stage versus S-saturated first-stage magmas (Vogel and Keays,
1997; Peck et al., 2001). Second-stage magmas have high PGE (Pd) and low Se and S
tenors whereas first-stage magmas are typified by higher Se and S tenors and lower
relative PGE (Pd) concentrations (Hamlyn et al., 1985; Hamlyn and Keays, 1986).
Sulphur and Se are readily interchangeable in such plots (Peck et al., 1993a) but Se is
much less soluble and less mobile than S under low temperature conditions
(Goldschmidt, 1954). As in the samples from the Nipissing gabbro suite, all of the River
Valley samples plot within the field of fertile second-stage magmas, contrasting with the
field of depleted first-stage magmas in which average mid-ocean ridge basalts (MORB)
plot. This implies that the parental magmas of the River Valley intrusion were S-
undersaturated, PGE-fertile and had not previously segregated sulphides.
Figure 6-13 are plots of S/Se values versus Pt+Pd concentrations for all mineralized
and unmineralized samples from Group-1; in Figure 6-13b, the concentrations of Pt+Pd
have been recalculated to metals in 100% sulphide. All but one of the samples (LU
sample 26875) from the main units of the River Valley intrusion (LU, IBZ and BX) plot
within the range of uncontaminated magmatic sulphides (Naldrett, 1981) and
approximate the estimated S/Se ratio for mantle of ~3300 (McDonough and Sun, 1995).
Recalculating the Pt+Pd concentrations to 100% sulphide (Fig. 6-13b) has the affect of
elevating the IBZ values closer to and overlapping most of the values from the BX,
371
suggesting that the IBZ sulphide contains as much PGE in the sulphide fraction as most
of the samples from the BX.
In Figure 6-14, S/Se ratios from the Group-1 data set is plotted against drill hole
(RV00-22) depth. In the lower IBZ the S/Se values rapidly increase then show a gradual
decline upward through the IBZ.
0.1
1
10
100
1000
10000
10 100 1000 10000 100000
Se (ppb)
Pd (p
pb)
LUIBZBXAVG MORB
First-Stage Magmas (MORB)
Second-Stage Magmas (Fertile)(<0.05wt% S)
MORB
Figure 6-12. Discriminant plot of Se (ppb) versus Pd (ppb) concentrations for
unmineralized (<0.05 wt% S) rocks from drill hole RV00-22, Dana North Deposit, River
Valley intrusion. Field Boundary and average MORB data are from Hamlyn et al.
(1985).
372
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1 10 100 1000 10000 100000
S/Se
Pt+
Pd (p
pb)
LUIBZBXBZFBXFW
sulphur loss magmaticcontamination(mss fractionation)
+R-factor
Konttijarvi Marginal Series(disseminated sulphide)
J-M Reef(Stillwater)
Merensky Reef(Bushveld)
(A)
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10000000
1 10 100 1000 10000 100000
S/Se
Pt+
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100
% su
lphi
de (p
pb)
LUIBZBXBZFBXFW
sulphur loss magmaticcontamination(mss fractionation)
+R-factor
(B)
Figure 6-13. Discriminant plots of whole-rock S/Se ratios against (A) whole-rock Pt+Pd (ppb) concentrations and (B) Pt+Pd concentrations recalculated to metals in 100% sulphide; the majority of samples plot within the field of magmatic sulphide (~1,000 to 5,000 S/Se; Naldrett, 1981). River Valley intrusion data are the mineralized (>0.05 wt% S) and unmineralized (<0.05 wt% S) samples from drill hole RV00-22. Data for Merensky Reef and average J-M Reef are from Naldrett (1981); data for average Konttijarvi Marginal Series rocks is from Iljina (1994).
373
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225
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2751000 10000 100000
S/Se
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBX
BZ
Figure 6-14a. Variation in whole-rock S/Se ratios for core samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
374
0
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100
125
150
175
200
225
250
2751 10 100 1000 10000
Pd (ppb)
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBXBZ
Figure 6-14b. Variation in whole-rock Pd concentrations (ppb) for core samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
375
0
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100
125
150
175
200
225
250
27510 100 1000 10000
Cu (ppm)
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBXBZ
Figure 6-15a. Variation in whole-rock Cu contents (ppm) for core samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
376
0
25
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100
125
150
175
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225
250
2750.1 1 10
Pd/Pt
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBXBZ
Figure 6-15b. Variation in whole-rock Pd/Pt ratios for core samples from drill hole RV00-22, Dana North Deposit, River Valley intrusion.
377
Through the LU, the S/Se values show the most consistent values and the highest average
S/Se value (3251) relative to the IBZ and BX. The FW and FBX have the highest S/Se
values which decrease rapidly through the lower BX and decrease further still upward
through the BX. The relatively higher S/Se values toward the base of the BX likely
reflect minor, local crustal contamination. The S/Se data presented in Figures 6-13 and
6-14 are consistent with the interpretation that most of the S in these rocks is magmatic.
The FW samples, along with the BZ and FBX samples, which contain numerous
inclusions of FW rocks, plot within the field of contamination (Fig. 6-13) suggesting
introduction of external sulphur from the immediate footwall rocks. However, the
marked difference between the S/Se ratios of the FW and FBX and the overlying units
(Fig. 6-14a), particularly the BX, suggest that the immediate FW is not likely the source
of the S in the mineralized (BX) zone.
An important trend in Figure 6-13 is the decrease in S/Se ratios with increasing Pd
concentrations; the sulphides with the highest Pd compositions also have the highest Se
values. As Pd and Se are both highly chalcophile elements, this trend can be explained in
terms of the Nernst partition coefficients for Pd and Se (DPd ~35,000 and DSe ~1770;
Peach et al., 1990). These sulphides, assumed to have formed under conditions of high R
factor (R = silicate:sulphide mass ratio; Naldrett et al., 1979), are rich in Pd and Se
because the segregated sulphide liquid came in contact with a large amount of silicate
magma. It is also suggested that these high R factors were not achieved entirely within
the River Valley intrusion, but rather in a deep-seated staging chamber (cf. James et al.,
2002a) where the initial parental magmas were crustally contaminated, as evidenced by
increased (Th/Yb)N values. This interpretation is given a lot of support because there is
no chalcophile metal depletion in the IBZ and LU which overly the BX, as would be
expected if the Pd-rich sulphides had formed in the River Valley intrusion. In
comparison, Keays and Lightfoot (2004) described depletion signatures in Ni, Cu and
PGE from rocks overlying both barren and mineralized sections of the lower contact of
the Sudbury Igneous Complex, reasoning that the sulphides had crystallized within the
complex itself, settling out of the magma and accumulating toward the base of the
complex.
378
Further plots of metal abundances versus drill hole (RV00-22) depth for Group-1
data are provided in Figure 6-15. Concentrations of Pt, Pd, Au, Cu and Ni are all highest
within the BX and with the exception of Cu and Ni, show a gradual decline upward
through the IBZ and LU. The concentrations of Cu and Ni show an upward, stepwise
increase through the IBZ and LU with relatively high Ni concentrations in the LU, most
likely a consequence of higher olivine in these rocks. This variation in Cu/Ni, and in
particular the pronounced increase in Ni in the LU, is best appreciated in the plot of
Cu/Ni which clearly shows a gradual decrease upward through the IBZ and LU relating
to an increase in the modal abundance of olivine and accordingly an increase in silicate-
bound Ni.
Studies by a number of authors (Hamlyn et al., 1985; Hamlyn and Keays, 1986;
Barnes et al., 1988; Hoatson and Keays, 1989; Barnes et al., 1992) have demonstrated
that Cu/Pd ratios could be used not only in ore genesis, to determine whether or not a
magma has experienced sulphide segregation, but also in exploration. Palladium is a
highly incompatible element in S-undersaturated magmas, accumulating in the residual
silicate fraction where it remains dissolved until such time as the magmas become S-
saturated (Keays, 1995). Primitive mantle has a Cu/Pd ratio of ~7700, whereas normal
MORB, which represents a S-saturated magma derived from incomplete (<25%) partial
melting of the upper mantle, has a Cu/Pd ratio of ~16,000 (Hamlyn et al. 1985; Keays,
1995). These authors have suggested that in a S-undersaturated magma, Cu/Pd ratios
would be much lower in the segregating sulphide melt relative to the silicate magma
because of the very high partition coefficient between sulphide and Pd relative to
sulphide and Cu. Barnes et al. (1992), in the their study of the Munni Munni Complex,
demonstrated that the Cu/Pd ratio of S-undersaturated magma is on the order of ~10,000.
Recent work on the Skaergaard Intrusion (Momme, Keays, and Tegner, unpublished data,
2004), which was formed by S-undersaturated magma derived from the Icelandic Plume
(Momme et al., 2003), has shown that the average Cu/Pd ratio of the Skaergaard rocks,
prior to S-saturation is about 13,000. A consequence of this is that rocks with Cu/Pd
ratios below ~10,000 should contain Pd-rich sulphides, whereas rocks with Cu/Pd ratios
>10,000, being S-saturated, may have lost Pd through earlier sulphide segregation. For
379
rocks from the River Valley intrusion, a value of 12,000 Cu/Pd was chosen to mark the
change from S-undersaturation to S-saturation (Fig. 6-16).
0
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150
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2751 10 100 1000 10000 100000 1000000
Cu/Pd
Dril
l Hol
e D
epth
(m)
LU
IBZ
BX
FW
FBXBZ
12,000 Cu/Pd
S-saturatedS-undersaturated
Figure 6-16. Variations in the whole-rock Cu/Pd ratio in core samples, plotted against diamond drill hole depth from drill hole RV00-22, River Valley intrusion. The marker line at 12,000 Cu/Pd signifies the approximate point of S-saturation and is based on the work of Hamlyn et al. (1985) and recent data from Momme, Keays, and Tegner (unpublished data, 2004).
380
All samples except 29633 from the LU (Group-1 data) have Cu/Pd values that are
<12,000 and plot as S-undersaturated; sample 29633 (~75 m level) is described as
containing numerous white quartz veins with up to 5% disseminated and veinlet
(secondary) chalcopyrite and should be ignored in terms of Cu/Pd values and S-
saturation.
As a consequence of the very extreme chalcophile nature of Pd relative to Cu,
samples with low Cu/Pd ratios contain PGE-rich sulphides are considered to have formed
under conditions of high R factors. The fact that rocks in the LU, which overly the PGE-
mineralized BX, do not contain significantly high Cu/Pd values suggests that these rocks
were formed from S-undersaturated magmas. The significance of this is that the
sulphides could therefore not have formed in the River Valley chamber but must have
formed at depth, in a staging chamber where the original magmas became crustally
contaminated and possibly driven to S-saturation as a result of this crustal contamination.
Selected bivariate plots for mineralized and unmineralized samples from Group-2 are
shown in Figure 6-17. Values of Pd/Ir increase whereas values of Ni/Cu decrease as
magmas become more evolved (Barnes, 1990) and this relationship allows for
discrimination between primitive (mantle-like) and evolved (continental flood basalt)
magmas. In Figure 6-17a, all of the samples from Group-2 data plot within the field of
layered intrusions (which includes high MgO basalts and flood basalts), as defined by
Barnes (1990). In Figure 6-17b, all of the samples plot along the trend of magmatic
sulphide with samples from the BX and IBZ falling toward the end-member of S-
undersaturated magmas. Figure 6-17c, plots wt% MgO against Pd/Ir ratios with all
samples falling well below the field of remobilized/hydrothermal mineralization as
estimated after Barnes (1990). This plot also attests to the relatively high MgO
concentrations in samples from the LU and BX relative to the IBZ.
Recognizable in all three plots of Figure 6-17, is the magmatic nature of the
sulphides. In these plots, the samples fall well away from the fields of
remobilized/hydrothermal mineralization as represented in Figures 6-17a and 6-17b by
hydrothermal mineralization from the Rathbun Lake (Rowell and Edgar, 1986) and South
Roby Zone, Lac des Iles Complex (J. Hinchey, unpublished data, 2004).
381
0.01
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0.01 0.1 1 10 100 1000
Ni/Cu
Pd/Ir
LU
IBZ
BX
BZ
FBX
FW
Rathbun Lake Avg
Lac des Iles - SRZ Avg
(A)
re-mobilized/hydrothermal mineralization
mantle
layered intrusions
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Cu/Ir
Ni/P
d
LUIBZBXBZFBXFWEast Bull LakeStreich DikeRathbun Lake AvgLac des Iles - SRZ Avg
Initially S-undersaturated magmas which underwent S-saturation late in the evolution
of the magma system
S-saturated magmas which lost PGE prior to emplacement
re-mobilized/hydrothermal mineralization
mss fractionation
(B)
Figure 6-17. Bivariate scatter plots of chalcophile metal ratios for mineralized and unmineralized samples (Group-2 data) from diamond drill hole RV00-22, Dana North Deposit, River Valley intrusion. The data in (A) Ni/Cu versus Pd/Ir and (B) Cu/Ir versus Ni/Pd support the interpretation that the majority of the sulphides are magmatic in origin.
382
1
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4 6 8 10 12
MgO (wt%)
Pd/Ir
14
LU
IBZ
BX
BZ
FBX
FW
(C)
remobilized/hydrothermal mineralization
Figure 6-17 (cont). Bivariate scatter plots of chalcophile metal ratios for mineralized and
unmineralized samples (Group-2 data) from diamond drill hole RV00-22, Dana North
Deposit, River Valley intrusion. (C) All samples lie well below the field of
remobilized/hydrothermal mineralization as estimated from Barnes (1990). Data for East
Bull Lake is from Peck et al. (1995); Streich Dike (Agnew Lake intrusion) is from Vogel
et al. (1999); average Lac des Iles – South Roby Zone (SRZ) is from J. Hinchey
(unpublished data, 2004); average Rathbun Lake is from Rowell and Edgar (1986).
Approximated trends and fields for remobilized/hydrothermal mineralization, layered
intrusions and mantle in (A) and (B) are after Barnes (1990).
383
Although in thin sections and hand specimens there is evidence for significant small-scale
redistribution of the sulphides - nearly all of the samples from the BX and many of the
samples from the IBZ are extensively recrystallized relative to the rocks of the LU - the
PGE are clearly controlled by sulphides (Figs. 6-10 and 6-11) and although originally
magmatic (Fig. 6-13) have been subjected to deuteric and/or hydrothermal redistribution.
Primitive mantle-normalized PGE (recalculated to metal abundance in 100%
sulphide) and chalcophile element diagrams for samples from Group-2 are shown in
Figure 6-18. All of the River Valley intrusion rocks are characterized by a positive slope
with the Pt-Pd-Au-Cu portion of the trends elevated relative to the Ni-Ir-Ru-Rh portion;
the Pt-Pd-Au-Cu portion of the trends range from about 10 times primitive mantle for Pt
and 100,000 times primitive mantle for Pd. The highest average trend is from the BX and
IBZ, which are also consistently higher in Rh, Pt, Pd and Au relative to the LU and BZ.
The FBX and FW patterns show the least enrichment in PGE-Au-Cu-Ni and have
elevated Ni/Ir and Cu/Pd values relative to the other samples. In the LU, IBZ, BX and
BZ, average Ni is depleted relative to average Ir (average Ni/Ir ranges from 0.03 to 0.66)
and in the IBZ, BX and BZ average Cu is depleted relative to Pd (average Cu/Pd ranges
from 0.15 to 0.35). Highest individual values of Ni/Ir (1.23) and Cu/Pd (1.75) are from
the LU, which are about 6-8 times those in the IBZ and BX. The IBZ and LU display
profiles that are broadly similar to the East Bull Lake intrusion and selected deposits such
as the J-M Reef (Stillwater) and the Marginal Series of the Konttijarvi intrusion (Portimo
Complex, Finland), characterized by large positive Pd anomalies, high Pd/Ir ratios and
high Cu/Ni ratios relative to mantle. Profiles from the IBZ and BX are most similar to
the sulphide patterns of the East Bull Lake intrusion, which is part of the same suite of
intrusions as the River Valley intrusion, and the Portimo Complex, which is part of a
geologically similar suite of intrusions in Finland (Iljina, 1994). Overall similarities in
the sulphide patterns and low Ni/Ir and Cu/Pd values in the River Valley intrusion, East
Bull Lake and Portimo Complex sulphides are distinct from the patterns displayed by the
Lac des Iles Complex and flood basalt sulphides which have lower average Ir, Ru and Rh
concentrations and higher Ni/Ir values (Fig. 6-18b). Although the Lac des Iles Complex
sulphides display similar degrees of Pd enrichment they are relatively depleted in Ir when
compared to samples from the River Valley intrusion.
384
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Ni Ir Ru Rh Pt Pd Au Cu
Met
al in
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% S
ulph
ide/
Prim
itive
Man
tle
LU AVG
IBZ AVG
BX AVG
Average EBLI
Streich Dike - Parental Magma
JM Reef - Stillwater
Portimo Finland
Average Flood Basalt
Avg SRZ - Lac des Iles
EBL Hydrothermal Avg
(B)
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Ni Ir Ru Rh Pt Pd Au Cu
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ulph
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itive
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29689 BX 29696 BX29702 BX 29707 BX29717 BX 29721 BX29733 BX 29744 BX29753 BX LU AVGIBZ AVG BZ AVGFBX AVG FW AVG
(E)
Figure 6-18. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) in core samples from diamond drill hole RV00-22, River Valley intrusion. (A) Average metal abundance for core samples from River Valley units compared with disseminated sulphide mineralization and PGE abundances from other mafic intrusions. (B) Individual values for the BX rocks. Data for “Average EBLI” is from Peck et al. (1995); “Streich Dike” is from Vogel et al. (1999); “J-M Reef” and average “Flood Basalt” are from Naldrett (1981); Portimo is from the Marginal Series in the Konttijarvi intrusive (Iljina, 1994); and, average Lac des Iles – South Roby Zone (SRZ) is from J. Hinchey (unpublished data, 2004). Mantle normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
385
Brügmann et al. (1989) interpreted the decoupling of Pd and Ir to be the result of deuteric
fluids which are thought to have dominated the development of sulphide mineralization at
Lac des Iles. Moreover, the average Pd/Ir ratio from the South Roby Zone (>5,000),
which is much higher than average Pd/Ir from the IBZ (143) and BX (149), is more
typical of Pd/Ir ratios reported from hydrothermal sulphide deposits (Keays et al., 1982).
6.7 Petrology and Geochemistry of the Breccia Unit
Sixteen samples, collected from the Breccia Unit at the Central Zone (“CZ” samples)
and South Zone (“SZ” samples), comprise sets of fragments and matrix (Fig. 6-2).
Descriptions of these fragment (“F” samples) and matrix (“M” samples) samples are
provided in Table 6-8 and a summary of the geochemical data is provided in Table 6-9.
A complete listing of the geochemical data for the fragment and matrix samples is
provided in Appendix 1 and petrographic descriptions are provided in Appendix 2. Sets
of the matrix and fragment samples were collected as close to one another as possible as
shown in Photos 6-10 and 6-11.
At the Central Zone, the exposed Breccia Unit comprises mainly fine-grained mafic
fragments hosted by medium- to coarse-grained gabbro and leucogabbro (Photo 6-10).
At the South Zone, the exposed Breccia Unit is dominated by mafic fragments that are
mainly fine-grained melagabbro and gabbro in a matrix of medium-grained gabbro
(Photo 6-11); fine-grained diabase dikes cut many of the fine-grained fragments (Photo 6-
12a). Especially evident at the South Zone, the ratio of mafic to felsic minerals in the
matrix may be widely variable over just a few metres (melagabbro to leucogabbro) with
no discernable break between the different rock types. One relatively large fragment of
layered gabbroic rocks, probably derived through stoping from the overlying Layered
Units, was noted at the South Zone (Photo 6-12b).
All eight matrix samples show well preserved, granular-hypidiomorphic igneous
textures with amphibole pseudomorphing pyroxene (Photo 6-13). In contrast, all eight
fragment samples are extensively recrystallized (Photo 6-14) with only rare preservation
of igneous textures. The matrix and fragment samples, although collected from surface
exposures, are considered to be representative of the fragments and matrix that were
intersected in drill core.
386
Photo 6-10. Central Zone (Dana North Deposit) fragment and matrix sampling from the Breccia Unit. (A) Diamond saw cuts in areas of fragment sample CZF01 and matrix sample CZM01. The cuts are about 22 cm long. (B) Locations of fragment sample CZF02 and matrix sample CZM02 as indicated by the red markers. Note the felsic nature of the matrix in both sample areas as compared to the mafic matrix in Photo 6-11. An eight centimetre ruler is provided for scale.
387
Photo 6-11. South Zone (Dana South Deposit) fragment and matrix sampling from the Breccia Unit. (A) Locations of fragment sample SZF01 and matrix sample SZM01 as labelled. A rock cut from an old sample site is indicated. (B) Locations of fragment sample SZF05 and matrix sample SZM05 as indicated by the red markers. Note the fine-grained nature of the fragments relative to the matrix in both photos. An eight centimetre ruler is provided for scale.
388
Photo 6-12. Fragments in the South Zone (Dana South Deposit). (A) Medium-grained gabbroic matrix hosting a fine-grained fragment that has been cut by a fine-grained diabase dike (arrow is area of cut). (B) Fragment of layered gabbroic rocks in massive medium-grained gabbro; the fragment was most probably derived from the “above” Layered Units. An eight centimetre ruler is provided for scale.
389
Photo 6-13. Photomicrographs typical of the matrix in the Breccia Unit, South Zone, Dana South Deposit. (A) Relict igneous textures with pyroxene (p-pyx) pseudomorphed by amphibole (p-pyx), interstitial plagioclase (plag), and fine-grained amphibole (amp). Plane light. (B) Same view as (A) but in crossed polars. Field of view is 8 mm wide for both photographs.
390
Photo 6-14. Photomicrographs typical of fragments in the Breccia Unit, South Zone, Dana South Deposit. (A) Extensively recrystallized with the mafic nature of the fragments reflected by the high percentage of fine-grained amphibole (amp) and lesser plagioclase (plag). Plane light. (B) Same view as (A) but in crossed polars. Field of view is 8 mm wide for both photographs.
391
Sample Location Type DescriptionSZM-01 SZ matrix massive; ~10 cm from SZF-01SZF-01 SZ fragment massive; subangular; ~20 cm long axisSZM-02 SZ matrix massive; ~50 cm from SZF-02SZF-02 SZ fragment massive; subangular; ~40 cm long axis; minor rusty spotsSZM-03 SZ matrix massive; ~24 cm from SZF-03; bleb and diss cpy-poSZF-03 SZ fragment massive; subangular; ~27 cm long axis; diss cpy-po/blebsSZM-04 SZ matrix massive; ~50 cm from SZF-04; diss cpy-poSZF-04 SZ fragment massive; subrounded; diss cpy-po/blebs; biotiteSZM-05 SZ matrix massive; ~20 cm from SZF-05; diss cpy-poSZF-05 SZ fragment massive; ~30 cm long axis; diss cpy-poCZM-01 CZ matrix massive; ~35 cm from CZF-01; diss/interstitial cpy-poCZF-01 CZ fragment massive; subangular/subrounded; ~40 cm long axis; diss cpy-poCZM-02 CZ matrix massive; ~5 cm from CZF-02; finely diss cpy-po; ~1% blue qtz; biotiteCZF-02 CZ fragment massive; biotite-hematite-K alteration; finely diss cpy-poCZM-03 CZ matrix massive; ~10 cm from CZF-03; finely diss cpy-po/bleb; <1% blue qtz; biotiteCZF-03 CZ fragment massive; subangular/subrounded; ~50 cm long axis; finely diss cpy-po
Sample Location Type Texture Field Name %VSSZM-01 SZ matrix mg gabbro nvSZF-01 SZ fragment fg melagabbro nvSZM-02 SZ matrix mg gabbro nvSZF-02 SZ fragment fg melagabbro trSZM-03 SZ matrix mg gabbro 3SZF-03 SZ fragment fg-mg melagabbro 2SZM-04 SZ matrix mg-cg leucogabbro 2SZF-04 SZ fragment mg melagabbro 3SZM-05 SZ matrix mg gabbro 1SZF-05 SZ fragment fg-mg gabbro 2CZM-01 CZ matrix cg leucogabbro 1-2CZF-01 CZ fragment fg-mg gabbro 1CZM-02 CZ matrix cg leucogabbro <1CZF-02 CZ fragment fg gabbro 1CZM-03 CZ matrix mg-cg gabbro <1CZF-03 CZ fragment fg gabbro 2
Table 6-8. Summary of matrix and fragment samples, collected from the Dana North
(Central Zone=CZ) and Dana South (South Zone=SZ) deposits, River Valley, intrusion.
diss=disseminated.
392
6.7.1 General Geochemistry
Whole-rock major element, trace element, REE and PGE data for the 16 matrix and
fragment samples are summarized in Table 6-9. A summary of CIPW normative
calculations completed on the 16 matrix and fragment samples is provided in Table 6-10;
rock types were determined on the basis of the weight % normative minerals. Four of the
five fragments collected from the South Zone classify as melagabbronorite and the fifth
as an olivine melagabbronorite. In contrast the matrix samples from the South Zone
classify as gabbronorite, olivine gabbronorite and olivine leucogabbronorite, and are
clearly more felsic than the fragment samples. One sample (fragment SZF05) is CIPW
quartz-normative and therefore quartz oversaturated, suggestive of contamination by
secondary quartz alteration, country rock interaction, or both. Five of the six samples
from the Central Zone classify as gabbronorite and one as a leucogabbronorite. As in the
South Zone, the matrix samples from the Central Zone are much more felsic relative to
the fragment samples. Two samples (matrix CZM01 and fragment CZF01) are only just
CIPW quartz-normative (silica-saturated). This characteristic may be the result of
primary quartz in matrix sample CZM01 but in fragment sample CZF01 it is likely the
result of contamination by secondary quartz alteration, country rock interaction, or both.
6.7.2 Major Element Variations
Several bivariate scatter plots show the variation in major elements from the
suite of fragments and matrix samples (Fig. 6-19). The plot of MgO versus SiO2 shows
that the matrix samples have elevated SiO2 relative to all fragments, excepting SZF04
which is CIPW quartz-normative, and illustrates the high MgO content of the fragments.
In Figure 6-19b, which plots Ir against MgO, the BX fragments from the South and
Central zones are clearly elevated in MgO relative to the matrix samples; this is in
agreement with the rock types and weight percent normative values from CIPW
normative calculations (Table 6-10). Figure 6-19c, which plots MgO versus Al2O3,
attests to the high aluminium concentration in the matrix samples relative to the
fragments and reflects the felsic nature (feldspar rich) of the matrix magma and of the
Central Zone fragments relative to the South Zone fragments. The scatter plot of Fe2O3*
versus MgO (Fig. 6-19d) clearly demonstrates the higher MgO and Fe contents in the
fragment samples relative to the matrix samples, suggesting that the magma(s) from
393
which the fragments was derived was/were much more primitive than the subsequent
magma(s) which formed the matrix. In Figure 6-19e, the high MgO values in the
fragments contrast those of the matrix and within the matrix samples themselves there is
elevated TiO2 in the Central Zone samples relative to the South Zone, likely reflecting the
more felsic nature of the Central Zone matrix.
Figure 6-19f, a scatter plot of Al2O3/TiO2 versus V, was used by Peck et al. (1993b)
as a fractionation index, utilizing the incompatibility of V in early formed silicate phases
(i.e. plagioclase). Figure 6-19f clearly illustrates that the matrix samples represent much
more fractionated magmas than those of the fragments, particularly the matrix samples
from the South Zone; this is in agreement with the elevated MgO compositions in the
fragments relative to the matrix. Figure 6-19f was also used by Peck et al. (1993b) to
demonstrate the relative proportions of cumulus plagioclase (reflected by increasing
Al2O3) and postcumulus minerals (reflected by increasing TiO2), where rocks with high
Al2O3/TiO2 are plagioclase-rich adcumulates (low cumulate porosity) and rocks with low
Al2O3/TiO2 are pyroxene-rich orthocumulates (high cumulate porosity); this assumes that
plagioclase is the principal cumulus phase. Figure 6-19f shows that the matrix rocks of
the South Zone are dominated by plagioclase-rich adcumulates whereas the fragments
from the South and Central zones trend towards pyroxene-rich cumulates.
6.7.3 Trace and Rare-Earth Element Variations
The relative amount of differentiation of a magma and/or its amount of interaction
with crustal material (contamination) is reflected by the incompatible trace elements Zr,
Y, Nb, Yb and La, whereby these elements become concentrated in magmas (rocks) that
are either more evolved and/or have interacted with crust. The plot of Zr versus Y (Fig.
6-20a) shows the primitive nature of the South Zone matrix relative to the matrix and
fragment samples from the Central Zone; three fragments (SZF01, SZF02 and SF04)
from the South Zone plot highest in Zr and Y, suggesting they are more evolved than the
other samples and/or they represent rocks that have interacted with crustal material.
Sample SF04 is the only sample that is CIPW quartz-normative, samples SZF01 and
SZF02 are CIPW olivine-normative, and all three samples have some of the highest wt%
TiO2 concentrations, suggesting contamination as the reason for elevated Y and Zr
concentrations.
394
Sample SZM01 SZF01 SZM04 SZF04 CZM01 CZF01 CZM03 CZF03Type M F M F M F M FSiO2 49.67 48.68 48.74 50.79 51.20 47.31 51.19 48.26TiO2 0.27 0.45 0.15 0.84 0.55 0.27 0.43 0.38Al2O3 16.65 5.96 23.47 5.74 19.06 11.58 15.89 11.02Fe2O3* 10.52 14.74 7.70 15.86 8.41 14.61 10.50 15.20MnO 0.18 0.26 0.10 0.25 0.15 0.24 0.19 0.24MgO 8.53 14.73 3.64 12.94 5.33 12.62 7.88 12.00CaO 10.23 12.04 10.15 9.64 11.10 7.55 9.32 7.44Na2O 2.68 0.57 3.15 0.41 2.61 0.35 2.26 0.71K2O 0.33 0.12 0.92 0.86 0.83 0.66 1.05 1.22P2O5 0.01 0.07 0.02 0.08 0.03 0.02 0.05 0.03
S 0.03 0.19 0.77 0.97 0.05 0.15 0.13 0.14Total 100.3 98.7 99.5 98.6 100.4 98.2 99.9 98.7Mg# 65.36 69.93 52.38 65.50 59.60 66.78 63.59 64.76
Pt 13.4 1.4 1637.0 683.0 61.3 8.2 20.7 4.6Pd 18.4 1.8 7164.0 1899.0 125.0 22.6 75.9 4.8Ni 189 399 632 427 107 428 164 308Cu 175 275 2586 2008 319 523 651 486La 2.42 2.68 2.83 10.17 6.61 3.17 6.40 4.53Ce 5.72 8.26 5.82 24.26 13.94 6.48 13.34 9.59Pr 0.79 1.29 0.75 3.11 1.70 0.83 1.71 1.26Nd 3.85 6.44 2.91 13.16 6.66 3.48 7.04 5.22Zr 9.90 46.10 15.30 69.60 38.80 16.20 45.20 21.00Sm 1.04 1.90 0.73 3.12 1.60 0.82 1.62 1.24Eu 0.57 0.41 0.51 0.52 0.72 0.34 0.90 0.61Ti 1223 1996 679 3813 2749 1243 2029 1757Gd 1.21 2.50 0.79 3.25 1.59 1.16 1.84 1.58Tb 0.21 0.39 0.11 0.50 0.30 0.18 0.31 0.27Dy 1.24 2.29 0.71 3.23 1.81 1.15 1.89 1.75Y 7.21 10.76 3.93 17.31 9.07 6.67 10.45 8.76
Ho 0.30 0.45 0.17 0.76 0.37 0.24 0.45 0.37Er 0.87 1.36 0.50 2.12 1.04 0.84 1.25 1.12Tm 0.14 0.21 0.08 0.32 0.16 0.12 0.21 0.17Yb 0.90 1.24 0.53 2.12 1.04 0.82 1.35 0.94Lu 0.16 0.18 0.07 0.32 0.15 0.14 0.22 0.17
∑REE 19.41 29.61 16.50 66.95 37.70 19.76 38.52 28.83(Th/Yb)N 0.52 4.91 4.49 8.40 7.31 3.40 4.98 3.89(Nb/Th)N 0.30 0.12 0.15 0.14 0.13 0.15 0.13 0.13
Zr/Sm 9.52 24.26 20.96 22.31 24.25 19.76 27.90 16.94Nb/Ta 2.22 4.40 2.78 8.75 6.36 6.67 5.91 3.18
Table 6-9. Summary of whole-rock geochemistry for matrix and fragment samples, River Valley, intrusion.
395
Sample SZM01 SZF01 SZM02 SZF02 SZM03 SZF03 SZM04 SZF04
Rock Type OGN MGN GN MGN GN OMGN OLGN MGNNorm Minerals
quartz 5.25plagioclase 56.06 18.82 56.93 21.77 55.86 23.10 75.19 15.17orthoclase 2.01 0.71 2.07 1.36 3.13 0.47 5.56 5.26diopside 14.66 37.99 13.34 36.69 12.54 27.40 2.55 29.95
hypersthene 13.50 34.72 19.41 30.56 19.76 31.46 3.33 37.02olivine 10.76 2.96 5.56 5.40 5.52 13.07 9.82
ilmenite 0.51 0.89 0.40 0.91 0.32 0.47 0.28 1.65magnetite 2.17 3.10 1.91 2.90 2.02 3.28 1.59 3.32
apatite 0.02 0.16 0.05 0.05 0.05 0.05 0.19zircon 0.01 0.01
chromite 0.04 0.09 0.06 0.09 0.06 0.09 0.01 0.04pyrite 0.06 0.42 0.19 0.04 0.78 0.51 1.65 2.12calcite 0.27 0.23 0.20 0.34 0.07 0.20 0.09 0.11
*Total: 100.06 100.10 100.07 100.11 100.11 100.10 100.12 100.09Sample SZM05 SZF05 CZM01 CZF01 CZM02 CZF02 CZM03 CZF03
Rock Type GN MGN LG GN GN GN GN MGNNorm Minerals
quartz 0.23 1.40plagioclase 55.28 26.28 60.76 32.96 51.49 25.78 50.25 30.67orthoclase 1.42 0.95 4.96 4.14 6.09 6.74 6.32 7.56diopside 14.60 26.91 13.98 7.75 14.80 19.52 13.15 11.38
hypersthene 23.44 40.20 16.97 49.56 21.62 35.18 26.49 45.48olivine 2.73 1.16 2.76 8.53 0.33 0.45
ilmenite 0.36 0.53 1.06 0.55 0.89 0.74 0.84 0.76magnetite 1.99 3.06 1.73 3.15 2.16 3.38 2.17 3.23
apatite 0.05 0.07 0.05 0.09 0.07 0.12 0.07zircon 0.01 0.01
chromite 0.04 0.09 0.03 0.09 0.04 0.09 0.06 0.09pyrite 0.17 0.85 0.11 0.34 0.06 0.06 0.28 0.32calcite 0.11 0.18 0.14 0.07 0.09 0.09
*Total: 100.08 100.14 100.09 100.13 100.07 100.09 100.11 100.10 Table 6-10. CIPW normative calculations for matrix and fragment samples from the
Central Zone (CZ) and South Zone (SZ), River Valley intrusion. *normalized to 100%;
"SZ" = South Zone, "CZ" = Central Zone, "M" = matrix, "F" = fragment; rock names
based on wt% normative minerals; OGN=olivine gabbronorite; MGN=melagabbronorite;
GN=gabbronorite; OMGN=olivine melagabbronorite; OLGN=olivine leucogabbronorite;
LG=leucogabbro.
396
45
46
47
48
49
50
51
52
0 2 4 6 8 10 12 14 16MgO (wt%)
SiO
2 (w
t%)
18
SZ MatrixCZ MatrixSZ FragCZ Frag
(A)
0
2
4
6
8
10
12
14
16
18
0.01 0.1 1 10 100
Ir (ppb)
MgO
(wt%
)
SZ MatrixCZ MatrixSZ FragCZ Frag
fragments
matrix
(B)
Figure 6-19a-b. Bivariate scatter plots showing the variation in whole-rock major element chemistry from the suite of fragments and matrix samples collected from the South Zone (SZ), Dana South Deposit, and Central Zone (CZ), Dana North Deposit, in the River Valley intrusion.
397
0
5
10
15
20
25
0 2 4 6 8 10 12 14 16 1
MgO (wt%)
Al 2O
3 (w
t%)
8
SZ MatrixCZ MatrixSZ FragCZ Frag
(C)
0
2
4
6
8
10
12
14
16
18
0 2 4 6 8 10 12 14 16
MgO (wt%)
Fe2O
3* (w
t%)
18
SZ MatrixCZ MatrixSZ FragCZ Frag
(D)
Figure 6-19c-d. Bivariate scatter plots showing the variation in whole-rock major element chemistry from the suite of fragments and matrix samples collected from the South Zone (SZ), Dana South Deposit, and Central Zone (CZ), Dana North Deposit, in the River Valley intrusion.
398
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0 2 4 6 8 10 12 14 16 1
MgO (wt%)
TiO
2 (w
t%)
8
SZ MatrixCZ MatrixSZ FragCZ Frag
(E)
1
10
100
1000
0 50 100 150 200 250 300Al2O3/TiO2
V (p
pm)
SZ MatrixCZ MatrixSZ FragCZ Frag
increasingfractionation
pyroxene-rich cumulatesplagioclase-rich adcumulates pyroxene-plagioclase mesocumulates
(F)
Figure 6-19e-f. Bivariate scatter plots showing the variation in whole-rock major element chemistry from the suite of fragments and matrix samples collected from the South Zone (SZ), Dana South Deposit, and Central Zone (CZ), Dana North Deposit, in the River Valley intrusion.
399
0
2
4
6
8
10
12
14
16
18
20
0 10 20 30 40 50 60 70 8Zr (ppm)
Y (p
pm)
0
SZ MatrixCZ MatrixSZ FragCZ Frag
increasing crustalinteraction
&fractionation
(A)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 10 20 30 40 50 60 70 8Zr (ppm)
(La/
Sm) N
0
SZ MatrixCZ MatrixSZ FragCZ Frag
increasing crustalinteraction
&fractionation
(B)
Figure 6-20. Bivariate scatter plots of trace element abundances and primitive mantle-normalized (N) ratio of La/Sm for fragment and matrix samples from the River Valley intrusion.
400
The ratio (La/Sm)N can provide good indications as to whether or not a magma has
interacted with crustal rocks, whereby increased La/Sm values suggest increasing crustal
assimilation. In Figure 6-20b, Zr is plotted against (La/Sm)N values for the matrix and
fragment samples. As in the plot of Y and Zr, the fragments from the South Zone show
the widest distribution with the majority of these samples having the lowest (La/Sm)N
values, reflecting their primitive (mafic) nature. The Central Zone samples show high
(La/Sm)N values and higher Zr concentrations in the matrix relative to the fragments.
This trend attests to the felsic nature of the Central Zone fragments and matrix relative to
the more mafic samples from the South Zone.
In Figure 6-21, Group-2 data from drill hole RV00-22 and data from the fragment
and matrix sample suite is plotted using primitive mantle-normalized (Th/Yb)N and
(Nb/Th)N. Distinct negative Nb and Ta anomalies, with respect to primitive mantle-
normalized data, are attributed to crustal contamination (e.g. Cox and Hawkesworth,
1985) and Th is preferentially enriched in continental crust (McDonough and Sun, 1995).
Plotting (Th/Yb)N against (Nb/Th)N is useful for modelling the effects of crustal
contamination on the composition of a proposed or known primary melt (e.g. Lesher et
al., 2001). Two of the four mixing curves, presented in Figure 6-21, were constructed by
systematic introduction of a crustal component (i.e. increasing Th) to the initial
compositions of N-MORB (Sun and McDonough, 1989), average boninite-like rock
(Piercey et al., 2001); data from the Povungnituk sedimentary rocks (Lesher et al., 2001)
represents continental crust. The third and fourth mixing curves were constructed by
assuming initial primitive boninite compositions that are expected to have 25% and 50%
less Nb relative to the boninite-like composition of Piercey et al. (2001). In Figure 6-21,
some of the rocks from the LU and IBZ plot along or above the N-MORB mixing curve
and suggesting compositions that are mixtures of N-MORB and continental crust (~10-
20% crustal contribution). All other rocks, including those from the BX and all fragment
and matrix samples and several of the LU and IBZ rocks, lie below the N-MORB mixing
curve and are displaced toward the mixing curves for boninite-like rocks and 25% and
50% depleted Nb; this suggests incorporation of some local footwall rocks. However,
more significantly, these depressed Nb values indicate that the BX (matrix and
401
fragments) were derived from a source magma that was very poor in Nb, such as a
boninite which would be much more depleted in Nb relative to N-MORB.
0.01
0.1
1
10
0.1 1 10 100
(Th/Yb)N
(Nb/
Th) N
LUIBZBXBZFBXFWSZ-MatrixSZ-FragmentCZ-MatrixCZ-FragmentStreich DikePovungnituk SedimentHuronian Sediment AvgBoninitic Avg
N-MORB
Continental Crust
Boninitic
-25% Nb
E-MORB
-50% Nb
10% crust
Figure 6-21. Mixing curves for primitive mantle-normalized values of (Th/Yb)N and
(Nb/Th)N using Group-2 data from drill hole RV00-22 and fragment and matrix samples
from the River Valley intrusion (SZ = South Zone; CZ = Central Zone). Continental crust
is represented by Povungnituk sedimentary rocks (Lesher et al., 12001). Data for N-
MORB and E-MORB are from Sun and McDonough (1989); data for Streich Dike is
from Vogel et al. (1998a); data for average (N=4) Huronian sedimentary rock is from
Easton (2003); data for average (N=4) Boninitic magma is from Piercey et al. (2001).
402
Chondrite-normalized REE patterns for the matrix and fragment samples are
provided in Figure 6-22, and a listing of the more important features of these plots is
summarized in Table 6-11. Average chondrite-normalized REE patterns for all sample
types are all elevated to about 10-20 times chondrite, exhibit LREE enrichment, and with
the exception of the average pattern for all fragments and the South Zone fragments, have
positive Eu anomalies. In general, Central Zone matrix and fragment samples have
patterns that are similar and near-parallel to one another, with LREE enrichment and a
narrow range in (La/Yb)N values (1.74 to 4.33).
Unit N Eu/Eu* La/Sm (La/Yb)N ∑REE ∑REE RangeRange Range Range Average ppm ppm
All Matrix 8 1.330-2.026 2.33-4.13 1.63-4.33 24 13-39All Fragment 8 0.492-1.335 0.90-3.87 0.58-3.28 26 9-67
SZ Matrix 5 1.533-2.026 2.33-3.88 1.63-3.64 15 13-19CZ Matrix 3 1.330-1.588 3.54-4.13 3.23-4.33 37 36-39
SZ Fragment 5 0.492-1.027 0.90-3.26 0.58-3.27 28 9-67CZ Fragment 3 0.977-1.335 2.86-3.87 1.74-3.28 23 20-29
Table 6-11. Principal features of trace and REE abundances and ratios for matrix and
fragment samples from the Central Zone (CZ) and South Zone (CZ), River Valley
intrusion. N=number of samples in the average or range. The value Eu/Eu*=
EuN/√[(SmN).(GdN)] was calculated using Geometric Mean method of Taylor and
McLennan (1985) where “N” indicates chondrite normalized.
403
1
10
100
La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Sam
ple/
Cho
ndrit
e
SZM01SZM02SZM03SZM04SZM05SZF01SZF02SZF03SZF04SZF05AVG-MAVG-F
(A)
1
10
100
La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Sam
ple/
Cho
ndrit
e
CZM01
CZM02
CZM03
CZF01
CZF02
CZF03
AVG-M
AVG-F
(B)
Figure 6-22. Chondrite-normalized rare-earth element plots for matrix and fragment samples from the Central (CZ) and South (SZ) zones at the Dana Lake area, River Valley intrusion. (A) Individual fragment and matrix samples from the South Zone. (B) Individual fragment and matrix samples from the Central Zone In each case, samples are compared to average compositions of matrix (AVG-M) and fragments (AVG-F). Normalizing values are from Lodders and Fegley (1998).
404
Fragment samples CZF01 and CZF02 are distinctly lower in total REE relative to the
other Central Zone samples and have very modest positive (CZF01: Eu/Eu*=1.05) to
slightly negative (CZF02: Eu/Eu*=0.98) Eu anomalies. The South Zone matrix and
fragment samples show the greatest range in chondrite-normalized REE patterns. Like
the Central Zone, the matrix samples from the South Zone have patterns that are similar
in total REE, are sub-parallel to one another and have large positive Eu anomalies. In
contrast, fragment samples from the South Zone are quite variable in their REE patterns.
Fragments SZF02 and SZF05 share similar sub-parallel and nearly flat REE patterns
(HREE elevated slightly relative to LREE), elevated about 6 to 9 times chondrite, and
with SZF02 exhibiting a slight negative Eu anomaly and SZF05 a slightly positive Eu
anomaly. These patterns are similar to those of MORB type magmas (Rollinson, 1993).
Fragment SZF04 exhibits a distinct REE pattern with the highest total REE (∑REE = 67
ppm), strong LREE enrichment, a pronounced negative Eu anomaly, and moderate HREE
enrichment. This distinct REE pattern and elevated REE concentrations, along with its
CIPW quartz-normative character, elevated (La/Sm)N value (2.11) and elevated Zr
content suggests interaction with crustal material and contamination. Vogel (1996)
presents similar data for a granite inclusion and a melagabbronorite pod from the Agnew
Lake intrusion which was interpreted to be the result of contamination of the
melagabbronorite pod by a granitic inclusion; the melagabbronorite pod also contained
substantial concentrations of blue quartz. Fragment SZF03 exhibits strong LREE
depletion, a moderate Eu anomaly (Eu/Eu* = 0.83) and the lowest total REE (∑REE = 9
ppm). On the basis of CIPW normative calculation, SZF03 classifies as an olivine
melagabbronorite and has the highest olivine-normative value (13.07 wt% olivine) of all
of the fragment-matrix samples. The potentially primitive nature of this rock with
elevated olivine and nominal plagioclase, would explain the low overall REE and the
distinct REE pattern. Fragment SZF01, elevated to about 10 times chondrite, exhibits a
distinct gull-wing pattern with elevated, concave down LREE, elevated HREE and a
distinct Eu anomaly (Eu/Eu* = 0.57); this REE pattern is similar to tholeiitic basalts (Sun
and Nesbitt, 1978).
The REE patterns for both the fragments and matrix present evidence for crustal
contamination with patterns from the South Zone fragments exhibiting the most dramatic
405
difference between individual samples (Fig. 6-22). The REE profiles exhibited by the
Central Zone and South Zone matrix are similar to the patterns from upper stratigraphy
rocks (i.e. Layered Units) of the River Valley intrusion, suggesting a common origin. In
addition, these samples have REE patterns that are similar to rocks from the Lower, Main
and Upper series of the East Bull Lake intrusion (James et al., 2002a) and from Lower
and Upper series rocks of the Agnew Lake intrusion Vogel (1996). In contrast, the
distinct REE patterns produced by the Central Zone fragments and in particular the South
Zone fragments, coupled with their high MgO concentrations relative to the matrix,
suggests that the fragments are exotic and were not cogenetic with the River Valley
intrusion magmas which formed the PGE-rich sulphide mineralization that occurs in the
matrix of the BX. If these REE patterns are primary then these fragments may represent
xenoliths that crystallized in a staging chamber and were subsequently entrained within
the magma(s) as it/they rose through the crust.
Primitive mantle-normalized multi-element plots for the fragment and matrix
samples are provided in Figure 6-23. The sample patterns are generally sub-parallel and
show the same relative arrangements between samples with the South Zone samples
exhibiting the greatest variation when compared to the Central Zone samples. All matrix
samples have strong positive Sr anomalies, indicative of high modal plagioclase and the
felsic nature of these rocks. Except for fragment CZF01, which is CIPW quartz-
normative, all fragment samples display strong negative Sr anomalies, indicative of low
modal plagioclase and the primitive nature of the fragments, particularly in the South
Zone fragments. All of the South Zone matrix samples display lower HREE (Sm to Yb)
concentrations relative to the South Zone fragments. In contrast, all of the Central Zone
matrix samples exhibit higher HREE (Sm to Yb) concentrations relative to Central Zone
fragments. All of the rocks exhibit negative Nb+Ta, P and Ti anomalies and low average
Nb/Ta values, ranging from 1.1 to 8.8. As discussed earlier, negative anomalies of the
high field strength elements Nb and Ta (strongly incompatible), the first series transition
metal Ti (moderately incompatible) and the alkaline earth element P (moderately
incompatible) are important indicators of a magmas interaction with a crustal reservoir
(Cox and Hawkesworth, 1985; Lightfoot and Naldrett, 1996).
406
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti Tb Y Tm Yb
Sam
ple/
Prim
itive
-Man
tle
AVG-M
AVG-F
Average SZM
Average SZF
Average CZM
Average CZF
(A)
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P* Sm Zr Ti Tb Y Tm Yb
Sam
ple/
Prim
itive
-Man
tle
SZM01SZM02SZM03SZM04SZM05CZM01CZM02CZM03AVG-MAVG-F
(B)
Figure 6-23. Primitive mantle-normalized multi-element diagrams for matrix and fragment samples from the Central Zone (CZ) and South Zone (SZ) areas of the River Valley intrusion. (A) Averages of matrix and fragment samples. (B) Average compositions of matrix and fragment samples compared with individual matrix samples. Normalizing values are from McDonough and Sun (1995).
407
In Figure 6-24, Group-2 data from drill hole RV00-22 and data from the fragment
and matrix sample suite is plotted using values of Zr/Sm and Nb/Ta (Foley et al., 2002).
Utilizing the diagram from Foley et al. (2002) it is apparent that all of the River Valley
samples plot with very low Nb/Ta and Zr/Sm values relative to MORB, primitive mantle,
continental crust, and modern adakites; Foley et al. (2002) considered adakites to be rare
modern analogues of Archaean crust-building magmatism, originating by melting of a
subducting basalt slab. Specifically, the distribution ranges from low Nb/Ta and low
Zr/Sm toward continental crust and adakites. These patterns are typical of tholeiites that
have been emplaced in a rifted environment, and are similar to those from established
rift-continental flood basalt regions (A.J. Crawford, pers. comm. 2004).
0
5
10
15
20
25
30
1 10 100 1000
Zr/Sm
Nb/
Ta
LUIBZBXBZFBXFWSZ-MatrixSZ-FragmentCZ-MatrixCZ-FragmentBoninitic Avg
Adakites
MORB
Primitive Mantle(intersection)
Continental Crust
Figure 6-24. Plot of Zr/Sm versus Nb/Ta ratios from whole-rock analyses of 44 unmineralized and mineralized River Valley intrusion samples (28 from Group-2 drill hole RV00-22, 16 from the fragment-matrix suite). The fields of MORB, continental crust and adakites (modern analogues of early continental crust) are approximated after Foley et al. (2002). Data for average (N=4) Boninitic magma is from Piercey et al. (2001).
408
Unit N Ir Au Pt Pd 3E Pt+Pd Ni CuAll Samples ppb ppb ppb ppb ppb ppb ppm ppmSZ Matrix 5 10.04 75 476 1973 2524 2449 340 1190CZ Matrix 3 0.64 19 30 71 120 101 137 396
SZ Fragment 5 7.94 72 349 1164 1585 1513 451 1076CZ Fragment 3 0.26 17 7 10 34 17 331 395
N Ir Au Pt Pd 3E Pt+Pd Ni Cuunmineralized** ppb ppb ppb ppb ppb ppb ppm ppm
SZ Matrix (SZM01) 1 0.33 8 13 18 40 32 189 175CZ Matrix 2 0.70 13 35 69 117 104 123 269
SZ Fragment (SZF02) 1 3.29 22 210 713 945 923 327 179CZ Fragment (CZF02) 1 0.25 9 7 3 19 10 256 175
Unit Se S S/Se Pd/Pt Cu/Ni Cu/Pd Pd/IrAll Samples ppb wt%SZ Matrix 2011 0.27 1323 4.1 3.5 603 196.5CZ Matrix 247 0.07 2834 2.3 2.9 5572 110.6
SZ Fragment 2295 0.36 1560 3.3 2.4 924 146.6CZ Fragment 766 0.11 1393 1.5 1.2 39089 39.3
Se S S/Se Pd/Pt Cu/Ni Cu/Pd Pd/Irunmineralized** ppb wt%
SZ Matrix (SZM01) 128 0.03 2344 1.4 0.9 9511 55.8CZ Matrix 138 0.04 2909 2.0 2.2 3913 98.2
SZ Fragment (SZF02) 231 0.02 866 3.4 0.5 251 216.7CZ Fragment (CZF02) 77 0.03 3896 0.4 0.7 59524 11.8
Table 6-12. Absolute and average chalcophile abundances and important ratios for matrix
and fragment samples from the Dana Lake area, River Valley intrusion. All assays from
Geoscience Laboratories in Sudbury; **unmineralized = ≤0.05 wt% S; Values for 3E =
Pt+Pd+Au.
409
The similar ratios from Nipissing Gabbro rocks, suggests that both the River Valley
magmas and those that formed the Nipissing Gabbro suite could have been feeders for
continental flood basalts. It should be pointed out, however, that the Zr/Sm and Nb/Ta
values may both be systematically low, and in the case of Zr, this is probably related to
insufficient digestion (open beaker digestion – see Section 2.2) of Zr during the ICP-MS
analytical process; ICP-MS Zr data may be one third to one half less than XRF Zr data
(A.J. Crawford, pers. comm. 2004), Assuming higher Zr compositions would therefore
shift these samples toward the fields of continental crust and adakites. Weyer et al.
(2002) reported a low Nb/Ta value of 4, but lower values, such as the ones in the current
study, are not known from literature.
Sample N Pd/Pt Cu/Ni Pd/Ir Cu/Pd Pd+Pt (ppb) Ni/Pd S/SeSZM01 1.4 0.9 55.8 9511 32 10272 2344SZM02 3.6 2.4 164.4 986 794 406 1164SZM03 3.5 5.2 154.2 1508 1621 291 1454SZM04 4.4 4.1 216.4 361 8801 88 1281SZM05 4.0 2.6 166.4 844 997 327 1196CZM01 2.0 3.0 104.2 2552 186 856 3067CZM02 1.4 1.6 62.5 17520 21 11120 2679CZM03 3.7 4.0 143.2 8577 97 2161 2790SZF01 1.2 0.7 22.4 153631 3 222905 1177SZF02 3.4 0.5 216.7 251 923 459 866SZF03 2.6 1.4 86.2 63929 16 44286 1825SZF04 2.8 4.7 130.1 1057 2582 225 1622SZF05 3.8 3.6 148.0 689 4043 189 1590CZF01 2.8 1.2 75.3 23142 31 18938 944CZF02 0.4 0.7 11.8 59524 10 87075 3896CZF03 1.0 1.6 21.6 102316 9 64842 2219
Average M (all): 8 4.1 3.4 193.3 708.4 1569 209.6 1426Average F (all): 8 3.3 2.0 144.6 1121.8 952 554.8 1532Average M SZ: 5 4.1 3.5 196.5 603.1 2449 172.6 1323Average M CZ: 3 2.3 2.9 110.6 5571.7 101 1921.3 2834Average F SZ: 5 3.3 2.4 146.6 924.2 1513 387.2 1560Average F CZ: 3 1.5 1.2 39.3 39088.8 17 32750.1 1393
Table 6-13. Chalcophile abundances and ratios for matrix and fragment samples, River
Valley intrusion. All assays from Geoscience Laboratories in Sudbury; SZ=South Zone;
CZ=Central Zone; M = matrix; F = fragment.
410
6.7.4 Chalcophile (PGE, Cu, Ni) Element Variations
On average, the South Zone samples contain higher average total PGE, Cu, Ni and S
concentrations, higher Pd/Pt and Pd/Ir ratios and lower S/Se and Cu/Pd ratios, relative to
samples from the Central Zone (Tables 6-12 and 6-13). In terms of unmineralized
samples (≤0.05 wt% S), matrix and fragment samples from both zones contain anomalous
to very anomalous PGE concentrations with magmatic S/Se ratios; in particular, SZF02
contains 210 ppb Pt and 713 ppb Pd, with 0.02 wt% S. Positive correlation exists
between the strongly chalcophile metals, suggesting strong sulphide control on the
distribution of the chalcophile metals. For example, there are modest to strong
correlations between Pd and Pt, S and Cu, and S and Ni, and moderate to weak
correlations between Cu and Ni, Cu and Pd, and Cu and Pt.
With the exception of matrix sample SZM01, all of the South Zone matrix samples
have the highest Pd/Ir ratios (Tables 6-12 and 6-13). Values of Pd/Ir increase as magmas
become more evolved (Barnes, 1990) and Pd/Ir values are higher in secondary
(hydrothermal) sulphide mineralization relative to magmatic sulphides (Keays et al.,
1982). The elevated Pd/Ir ratios in the South Zone matrix samples and in the South Zone
fragment sample SZF02 may be indicative of slightly more evolved magma sources
and/or a higher percentage of secondary sulphide mineralization; the latter may be more
applicable to sample SZF02. Except for fragments SZF02, SZF04 and SZF05, the matrix
samples also have much higher PGE concentrations than the fragments, suggesting that
the PGE were introduced by way of the matrix magma(s) and that subsequent
impregnation of the fragments by remobilized sulphides, perhaps by means of deuteric or
hydrothermal fluids, resulted in elevated PGE compositions within select fragments.
S/Se values for mineralized (maximum 3% visible sulphide) and unmineralized
(<0.05 wt% S) matrix and fragment samples from the South and Central zones have
averages of approximately 1500, and range from 866 to 3896 (Fig. 6-25; Table 6-13).
These values are consistent with the interpretation that most of the S in these rocks is
magmatic as these values are typical of magmatic sulphides from other mafic intrusions
(Eckstrand et al., 1989), are well within the range of uncontaminated magmatic sulphides
(Naldrett, 1981; Eckstrand and Hulbert, 1987), and approximate the mantle value of 3333
(McDonough and Sun, 1995).
411
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Figure 6-25. Discriminant plots of whole-rock S/Se ratios against (A) whole-rock Pt+Pd (ppb) concentrations and (B) Pt+Pd concentrations recalculated to metals in 100% sulphide; the majority of samples plot within the field of magmatic sulphide (~1,000 to 5,000 S/Se; Naldrett, 1981). River Valley intrusion data are the mineralized (>0.05 wt% S) and unmineralized (<0.05 wt% S) matrix and fragment samples from the Central Zone (CZ) and South Zone (SZ). Data for Merensky Reef and average J-M Reef are from Naldrett (1981); data for average Konttijarvi Marginal Series rocks is from Iljina (1994).
412
Average S/Se values for matrix and fragment samples from the South Zone are about
1488 and 1416, respectively, and median values are about 1281 and 1590, respectively.
Average S/Se values for matrix and fragment samples from the Central Zone are 2845
and 2353, respectively and median values are about 2790 and 2219, respectively. The
slightly higher average and median S/Se values for Central Zone matrix samples, relative
to Central Zone fragments, is suggestive of minor contamination in the matrix magma.
Samples SZF02 and CZF01, which are extensively recrystallized and altered in thin
section, have S/Se values that are below 1000 which suggests sulphur loss (Reeves and
Keays, 1995), and small-scale redistribution of the chalcophile elements, likely the result
of weathering, secondary alteration and/or metamorphism. The introduction of
sedimentary sulphides is known to result in S/Se values >20,000 (Naldrett, 1981). The
paucity of S/Se values >20,000 in this data set suggests that the introduction of external
sulphur, potentially derived from bordering Archaean paragneiss and Huronian
Supergroup country rocks, was unlikely or minor, and that assimilation and interaction
with the country rocks did not play a major role in the development of the contact-type
sulphide mineralization. Peck et al. (1993a) noted similar S/Se trends from contact-type
mineralization in the East Bull Lake intrusion. It is important to note that in very
dynamic magmatic ore systems (i.e. high R factors) the effects of crustal contamination
are masked by the R factor process (Lesher and Burnham, 1999); a similar affect is noted
for Re-Os isotopes by Lambert et al. (1998).
Figure 6-26a is a plot of Se and Pd data for mineralized and unmineralized fragment
and matrix and RV00-22 drill core samples (Group-1). With the exception of South Zone
fragment SZF01, all of the samples plot within the field of second-stage magmas (S-
undersaturated field), contrasting with the first-stage or depleted magma field in which
average mid-ocean ridge basalts (MORB) plot. As discussed earlier, this implies that the
parental magmas of the River Valley intrusion were introduced into the chamber as PGE
metal-fertile magmas which had not previously segregated sulphides.
Mineralized and unmineralized fragment and matrix and drill hole RV00-22 (Group-
1) core samples are presented on a metal ratio plot of Cu/Pt versus Ni/Pd (Figure 6-26b).
413
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Second-Stage Magmas(Fertile)
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DEPLETED
(All Samples: RV00-22 and Matrix-Fragments)
ENRICHED
MANTLE
FloodBasalts
PGE-dominated deposits
increasing PGEin sulphide
Figure 6-26. Plots showing variations in concentrations for mineralized (>0.05 wt% S) and unmineralized (<0.05 wt% S) matrix and fragment samples and Group-1 core samples from drill hole RV00-22. (A) Discriminant plot of Se (ppb) versus Pd (ppb). Fragment and matrix samples are from the Central Zone (CZ) and South Zone (SZ). Field Boundary and average MORB data are from Hamlyn et al. (1985). (B) Plot of Cu/Pt versus Ni/Pd ratios. Fields of mantle rocks, flood basalts, and PGE-dominated deposits (i.e. Reef-type mineralization in the Bushveld, Stillwater and Penikat intrusions) are approximated after Barnes et al. (1993).
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Several authors (e.g. Barnes et al., 1988; Theriault et al., 2000) have utilized these ratios
to evaluate the effects of partial melting, crystal fractionation, and sulphide segregation
on the PGE composition of sulphides. The plot has been subdivided into three main
fields which allow for the comparison of each sample’s composition and whether or not it
is PGE-enriched or PGE-depleted relative to mantle. The samples span the fields of
PGE-depleted, mantle and PGE-enriched sulphides with the majority plotting within the
enriched field. Except for fragments SZF02, SZF04 and SZF05, which plot within the
field of PGE-enriched sulphides, the matrix samples plot with higher PGE relative to five
of the eight fragment samples; the latter plot well within the field of PGE-depleted
sulphides. The three PGE-rich fragments - SZF02, SZF04 and SZF05 – are suspected of
containing remobilized PGE and also have much higher PGE concentrations than the
matrix, suggesting that the PGE were introduced by way of the matrix magma(s).
Specifically, it is possible that post-crystallization impregnation of the fragments by
remobilized sulphides, perhaps by means of deuteric or hydrothermal fluids, resulted in
elevated PGE compositions within select fragments. Alternatively, if the fragments are
indeed xenoliths, then the PGE-rich sulphides may have co-precipitated early on with the
silicate minerals that comprise the fragments, perhaps within a staging chamber.
Primitive mantle-normalized plots of PGE, Au, Cu and Ni concentrations in 100%
sulphide for the matrix and fragment samples are provided in Figure 6-27. Average
compositions of the fragment and matrix samples are characterized by positive slopes
with the Pt-Pd-Au-Cu portions elevated relative to the Ni-Ir-Ru-Rh portion; the average
matrix and fragment patterns are almost identical. Profiles from the average River Valley
intrusion samples are compared with average values for the J-M Reef (Stillwater),
representing reef-type PGE deposits, average flood basalt related to Cu-Ni-PGE deposits
such as Noril’sk (Russia), average Konttijarvi Marginal Series values from the Portimo
Complex (Finland), representing contact-type mineralization from a similar geological
environment, average values from the East Bull Lake intrusion (contact-type
mineralization), and average values from the South Roby Zone of the Lac des Iles
Complex, representing remobilized/hydrothermal deposits (J. Hinchey, unpublished data,
2004).
415
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(A)
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SZM01SZM02SZM03SZM04SZM05Average MatrixSZF01SZF02SZF03SZF04SZF05Average FragmentAverage EBLIAvg SRZ - Lac des Iles
(B)
Figure 6-27ab. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) from matrix and fragment samples, River Valley intrusion. (A) Average metal abundance for matrix and fragment samples from the River Valley intrusion compared with disseminated sulphide mineralization and PGE abundances from other mafic intrusions. (B) Average chalcophile abundance of matrix and fragment samples compared with individual samples from the South Zone, Dana South Deposit.
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CZM01
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CZF01
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Avg SRZ - Lac des Iles
(C)
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SZM01SZM02SZM03SZM04SZM05CZM01CZM02CZM03Average MatrixAverage FragmentAverage EBLIAvg SRZ - Lac des Iles
(D)
Figure 6-27cd. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) for matrix and fragment samples, River Valley intrusion. (C) Average chalcophile abundance of matrix and fragment samples compared with individual samples from the Central Zone, Dana North Deposit. (D) Average chalcophile abundance of matrix and fragment samples compared with individual matrix samples from the Central and South zones.
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SZM01
SZM02
SZM03
SZM04
SZM05
Average Matrix
Average Fragment
Average EBLI
Avg SRZ - Lac des Iles
(F)
Figure 6-27ef. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) for matrix and fragment samples, River Valley intrusion. (E) Average chalcophile abundance of matrix and fragment samples compared with individual fragment samples from the Central and South zones. (F) Average chalcophile abundance of matrix and fragment samples compared with individual matrix samples from the South Zone.
418
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SZF01
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CZM01
CZM02
CZM03
Average Matrix
Average Fragment
Average EBLI
Avg SRZ - Lac des Iles
(H)
Figure 6-27gh. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) for matrix and fragment samples, River Valley intrusion. (G) Average chalcophile abundance of matrix and fragment samples compared with individual fragment samples from the South Zone. (H) Average chalcophile abundance of matrix and fragment samples compared with individual matrix samples from the Central Zone.
419
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(I)
Figure 6-27i. Primitive mantle-normalized chalcophile metal abundances (recalculated to metals in 100% sulphide) for matrix and fragment samples, River Valley intrusion. (I) Average chalcophile abundance of matrix and fragment samples compared with individual fragment samples from the Central Zone. All of the plots in Figure 6-27 (A to I) use Mantle normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995). Data for “Average EBLI” is from Peck et al. (1995); “Streich Dike” is from Vogel et al. (1999); “J-M Reef” and average “Flood Basalt” are from Naldrett (1981); Portimo is from the Marginal Series in the Konttijarvi intrusive (Iljina, 1994); and, average Lac des Iles – South Roby Zone (SRZ) is from J. Hinchey (unpublished data, 2004). Mantle normalizing values are from Barnes et al. (1988) and McDonough and Sun (1995).
420
Platinum-group element profiles from average fragment and matrix compositions are
most similar to the East Bull Lake intrusion but are also similar to the sulphides of the
Konttijarvi Marginal Series (Fig. 6-27a). Average River Valley intrusion, East Bull Lake
and Konttijarvi Marginal Series data are distinguished from flood basalt (Naldrett, 1981)
by distinctly lower Ni/Ir and Cu/Pd values, higher total Pd abundances, and much higher
Ir and Ru abundances (Fig. 6-27a). The average PGE pattern from the Lac des Iles
Complex, considered an example of deuteric or hydrothermally altered sulphide
mineralization (Brügmann et al., 1989), is distinct from the average River Valley
intrusion sulphides with higher Pd abundance and lower Cu, Ir, Ru, Rh and Pt
abundances, suggesting that development of the River Valley intrusion sulphides is
dominated by magmatic processes.
Although patterns of average PGE in sulphide concentrations are quite similar for the
River Valley intrusion samples, in detail there is much more difference when considering
individual matrix and fragment PGE patterns (Fig. 6-27b-i). All of the matrix samples
from the South Zone exhibit patterns that approximate the average matrix and fragment
profile as well as the average East Bull Lake PGE data (Fig. 6-27f); matrix sample
SZM01 is slightly depleted in Ir and Pd, resulting in a lower Pd/Ir value (1.3) relative to
other matrix samples. South Zone fragment samples SZF01 and SZF03 exhibit distinct
PGE profiles in comparison to other fragment samples from the South Zone (Fig. 6-27g),
with depleted overall abundances of PGE (in 100% sulphide), high Ni/Ir values (8.4 and
11.0) and high Cu/Pd values (24.1 and 10.0). These patterns and ratios are very similar to
those reported by James et al. (2002a) for structurally controlled (remobilized)
mineralization in the East Bull Lake intrusion. In the River Valley intrusion rocks, this
may reflect preferential secondary reconcentration of low-melting-point precious metals
(i.e. Pd, Pt and Au) and Cu into the fragments during post-magmatic processes (i.e.
hydrothermal redistribution); the precious metals could have been sourced from new
influxes of magma (matrix) and/or previously existing magmatic sulphide mineralization
(assimilated fragments).
Matrix and fragment samples from the Central Zone show the greatest deviation
from the “normal PGE trend” as established by the average matrix and fragment
compositions from the River Valley intrusion and average composition from the East
421
Bull Lake intrusion (Fig. 6-27c). Central Zone matrix samples CZM01 and CZM03 are
the only two samples of the six that exhibit PGE patterns similar to the “normal PGE
trend” including high abundance in Pd relative to the other metals and low Ni/Ir and
Cu/Pd values; sample CZM03 has a lower total abundance of PGE but follows a similar
step-wise pattern (Fig. 6-27h). Samples CZM02, CZF01, CZF02 and CZF03 share
similar PGE profiles with relatively lower total PGE abundance, low Pd/Ir values, and
high Ni/Ir and Cu/Pd ratios. These patterns and ratios are similar to the South Zone
fragments SZF01 and SZF03, and as in these samples likely record a predominance of
remobilized sulphide mineralization.
6.8 Modelling of Sulphide Compositions
The sulphide compositions of the 128 samples from the River Valley intrusion, 112
from drill hole RV00-22 and 16 from the fragment-matrix sample suite, were modelled
using the mass balance R factor equation of Campbell and Naldrett (1979) as described in
Section 2.3.5. Utilizing the Pd versus Cu/Pd diagram of Barnes et al. (1993) the
modelling curves (R factor curves) are plotted along with the Pd and Cu/Pd values from
the 128 mineralized and unmineralized samples (Fig. 6-28). The average Cu and Pd
abundances of the Layered Units (Group-2 data: 21 ppb Pd, 90 ppm Cu, 4260 Cu/Pd,
0.04wt% S) are used as the best estimate for the parental magma composition as they
represent unmineralized and S-undersaturated magmas.
In Figure 6-28, the majority of LU sulphides and all of the Central Zone fragment
and matrix sulphide can be modelled using R factors of less than 1000. The bulk of the
BX sulphide, along with sulphide from South Zone fragments and matrix can be
modelled with R factors that range from 1000 to 10,000. Sulphide from several BX and
one South Zone fragment can be modelled with R factors between 10,000 and 100,000.
Nearly all of the sulphide from IBZ and a number of BX and LU samples fall below the
sulphide-silicate tie lines for R=10,000 and R=100,000 which suggests loss of Cu,
probably due to hydrothermal redistribution. However, this is not reflected in the S/Se
data in which the IBZ and BX have comparable S/Se ratios and do not show any S loss.
The results suggest that the main mineralized rocks (BX) of the Dana North Deposit at
the River Valley intrusion, experienced R factors between about 1000 and 10,000. In
comparison, Peck et al. (2001) suggested that average disseminated sulphide
422
compositions (25 PGE-rich samples) from the Lower and Marginal Series of the East
Bull Lake intrusion could be modelled using R factors that ranged from 2100 to 6000.
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ENRICHED
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100%
R=100
R=1000
R=10,000
R=100,000
R=2000
1.0%
Figure 6-28. Discrimination plot of Pd versus Cu/Pd showing the sulphide compositions
for 128 samples (112 from Group-2 data – drill hole RV00-22, 16 fragment-matrix
samples) from the River Valley intrusion. Tie lines are mixing lines between sulphide and
silicate melt at various R factors, ranging from 100 to 100,000, and determined after
methods described by Campbell and Naldrett (1979) and Naldrett (1981). Markers along
each of the mixing lines represent percentages of precipitated sulphide melt at 0.1%,
1.0%, and 10% through to 100% sulphide. The star symbol represents the estimated
parental magma composition derived from the average composition of 12 unmineralized
(<0.05 wt% S) rocks from the Layered Units (21 ppb Pd, 90 ppm Cu, 4260 Cu/Pd,
0.04wt% S) and assuming a sulphide component of 36.5 wt%. Fields of mantle rocks,
and those depleted and enriched in PGE relative to mantle are taken from Barnes et al.
(1993).
423
Barnes et al. (1997) reported ranges in calculated R factors for disseminated magmatic
sulphide from several intrusions related to intraplate magmatism (mantle plume and rift-
related), including 1000 to 20,000 (Noril’sk-Talnakh), 200 to 2000 (Cape Smith), 2000 to
10,000 (Duluth Complex), and 200 to 2000 (Muskox).
Many of the samples, including most of the LU and many of the IBZ samples, have
Cu/Pd values that are at or above that of mantle (Fig. 6-28). If the LU rocks approximate
the initial chemistry of the parent magmas to the River Valley intrusion, then it is
probable that these magmas became S-saturated early on in a deep seated staging magma
chamber (cf. James et al., 2002a; see Chapter 7). This also suggests that prior to their
emplacement, the magmas underwent some degree of sulphide fractionation with
removal of what was probably a small amount of sulphide. During their ascension
through the crust and into the River Valley magma chamber, these S-saturated magmas
would have become S-undersaturated as a result of adiabatic decompression, which
increases the solubility of S in the melt (Mavrogenes and O’Neill, 1999; Momme et al.,
2002a). Barring any significant contamination en route through the crust, the magmas
would have remained S-undersaturated until emplacement in the upper crust (River
Valley chamber), at which time they became S-saturated, segregating sulphides at
varying R factors (Fig. 6-28). It is evident that some of the magma(s) became S-saturated
and began precipitating sulphide at the Pd-Cu/Pd value indicated by the estimate of initial
magma composition (star symbol, Fig. 6-28). However, it is also apparent that other
magma(s) became S-saturated at higher Cu/Pd and lower Pd values, suggesting that the
estimated initial composition for Pd is too high to explain all of the rock compositions
and/or that magma(s) were introduced which had lower initial Pd composition(s).
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6.9 Summary
The East Bull Lake suite of intrusions, and specifically the River Valley intrusion,
present excellent exploration targets for contact-type PGE-Cu-Ni sulphide mineralization
and an understanding of the emplacement environment and origin of the PGE-bearing
sulphides is paramount to future discoveries. As with other East Bull Lake suite
intrusions (i.e. East Bull Lake and Agnew Lake) most of the sulphide mineralization
discovered to date has been within fragment-bearing rock units that are concentrated or
localized along the margins (sidewalls and/or basal contacts) of the intrusions; these are
the Marginal Series rocks in the case of the River Valley intrusion. On the basis of this
and previous studies, along with unpublished data from Pacific North West Capital Corp.
and Anglo American Platinum Corporation Limited, a number of conclusions can be
made regarding the chemistry and petrogenesis of the River Valley intrusion in the
context of the sulphide mineralization.
Controls on Mineralization
1) The identification of reasonably preserved primary igneous contacts between the
sulphide-bearing Marginal Series rocks and the migmatitic and/or sedimentary
country rocks is of particular importance in terms of exploration as it is these regions
of the intrusions that show the best preservation of the Marginal Series rocks.
2) Numerous northeast-trending linear fault and shear zones, up to 1 kilometre wide,
dissect the stratigraphy, including that of the mineralized Marginal Series. The
displacement along these linear features appears to be predominantly strike-slip
(currently, the dip-slip components are poorly constrained) and on the order of 10’s
of metres; consequently tracing the strike of the Marginal Series rocks is not
impractical.
3) Preserved regions (blocks) of Marginal Series rocks between the large-scale fault and
shear zones are typically several hundred metres in length and therefore constitute
regions of potentially continuous sulphide mineralization; these are important from
the standpoint of large-tonnage bulk mining operations.
4) There is a regional pattern of metamorphic grade, ranging from greenschist facies in
the northeastern part of the intrusion (i.e. Dana North Deposit, Fig. 6-2) to granulite
425
facies in the furthest southeastern parts of the intrusion (i.e. Razor, Fig. 6-1).
Although yet to be confirmed, there may be an important connection between
metamorphic grade and PGE concentration, as the highest grades and greatest
accumulations of PGE are found in the areas of lower metamorphic grade (i.e. Dana
North and South Deposits).
5) A remarkably consistent stratigraphy for the Marginal Series rocks exists in the
region between the Dana North and the Lismer’s South deposit (Figs. 6-2 and 6-3).
Contact-type disseminated PGE-Cu-Ni sulphide mineralization is concentrated
within the Breccia Unit of the Marginal Series.
6) Anomalous PGE values (>500-1000 ppb Pt and/or Pd) occur throughout the Breccia
Unit with still higher concentrations of PGE (>3000 ppb Pt and/or Pd) occurring as
high-grade regions within the lower one-third of the mineralized zones.
Major Element Geochemistry
1) The rocks of the Marginal Series are sub-alkaline, and on the basis of CIPW
normative calculations, are dominated by olivine-normative gabbronorite to olivine
leucogabbronorite. Fragment compositions (CIPW melagabbronorite and
gabbronorite) and are much more mafic than the hosting matrix.
2) Rocks of the BX have the highest individual (11.8 wt% MgO) and average (~9.3
wt%) MgO compositions, reflecting the high proportion of high magnesian (mafic)
fragments in this unit. The higher MgO compositions of the fragments relative to the
enclosing matrix suggests that the magma(s) from which the fragments were derived
was/were much more primitive than the magma(s) that formed the matrix.
3) In the BX, a strong correlation exists between elevated SiO2, TiO2, Pt+Pd and the
presence of patchy blue quartz, corroborating the empirical observation that higher
PGE concentrations are more commonly associated with blue quartz; Ma et al.
(2001) attributed the anomalously blue colour to sub-micrometre inclusions of
ilmenite in the quartz.
426
Trace Element Geochemistry
1) Chondrite-normalized REE patterns for the vast majority of River Valley rocks
are characterized by LREE enrichment, have narrow ranges in (La/Yb)N, and
display modest positive Eu anomalies. The REE patterns of the BX are similar to
those of the upper stratigraphy rocks, suggesting a common origin.
2) The consistently low (La/Sm)N values through the BX and IBZ and their
similarity to the overlying LU suggests that contamination from local footwall
rocks was insignificant. Moreover, the very high (Th/Yb)N values (~2 to 10 times
that of primitive mantle) are interpreted to be the consequence of extensive crustal
contamination of a mantle-derived magma.
3) The majority of REE patterns exhibit negative Nb and Ta anomalies but in each
case the negative Nb anomalies are much larger than those of Ta. This is a
characteristic feature of boninitic magmas (A.J. Crawford, pers. comm. 2004).
4) All of the samples from the River Valley intrusion have very low Nb/Ta and
Zr/Sm values relative to MORB, primitive mantle, continental crust and modern
adakites. This is interpreted to mean that the River Valley rocks have interacted
with an extensive crustal reservoir, adopting crustal signatures typical of rift-
related magmas and/or continental flood basalt.
5) Five of the six South Zone fragments display very distinct chondrite-normalized
REE patterns and have very high MgO compositions relative to the host matrix.
This suggests that these fragments were not cogenetic with the magmas that
formed the bulk of the River Valley intrusion, but rather that these are xenoliths
that were probably carried into the RV chamber by PGE-rich magmas which are
now represented by the matrix rocks and which probably introduced the bulk of
the PGE-rich sulphides.
Chalcophile Geochemistry
1) The estimated background PGE-Cu-Ni composition for River Valley intrusion
rocks, which also provides an estimate for the parental magma composition, is 6
ppb Au, 22 ppb Pt, 19 ppb Pd, 70 ppm Cu and 97 ppm Ni.
427
2) Strong correlations exist between the chalcophile elements indicating that the
PGE, and particularly that those is in the BX, are strongly sulphide controlled.
Metal ratio diagrams (Ni/Cu vs Pd/Ir, Cu/Ir vs Ni/Pd, wt% MgO vs Pd/Ir) also
support a magmatic origin for the vast majority of the PGE.
3) Sulphides in chondrite-normalized PGE diagrams exhibit patterns that are
consistent with a magmatic origin for the sulphides, with some variations that can
be attributed to local hydrothermal redistribution of the sulphide. Total metal
abundance and patterns for the contact-type disseminated sulphides of the River
Valley intrusion are similar to those from other intrusions with contact-type
mineralization (i.e. East Bull Lake intrusion, Canada; Konttijarvi-Portimo
Complex, Finland) and contrast those with known hydrothermal mineralization
(i.e. Lac des Iles Complex).
4) Discrimination plots of Se versus Pd show that the magmas from which the
sulphides precipitated were PGE metal-fertile second-stage magmas (S-
undersaturated) that had not previously segregated sulphides to any large amount.
Discrimination plots of S/Se versus Pt+Pd add further support to the interpretation
that the sulphide is magmatic in origin, but also indicate that the immediate
footwall rocks are not the source of the S in the mineralized BX.
5) If the PGE-rich sulphides had formed within the River Valley chamber, it would
be expected that the rock units (i.e. the IBZ and LU) overlying the mineralized
unit (i.e. the BX) would be strongly depleted in the PGE, as their counterparts are
in other mineralized layered intrusions and the Sudbury Igneous Complex (Keays
and Lightfoot, 2004). As this is not the case, then the sulphides must have been
formed prior to the River Valley “feeder” magmas entering the River Valley
magma chamber.
6) The Cu/Pd ratios for the all of the River Valley samples are <12,000, the value at
which S-saturation is expected to occur, and therefore represent S-undersaturated
magmas.
7) Samples with low Cu/Pd ratios are considered to have formed under high R factor
conditions. The majority of the sulphides from the BX can be modelled using R
428
factors that range from about 1000 to 10,000 and a small number from the BX can
be modelled with R factors between 10,000 and 100,000.
429
CHAPTER 7: DISCUSSION AND PETROGENESIS
7.1 Summary and Implications
Understanding the behaviour of the chalcophile elements is not only important in
characterizing and understanding the petrogenesis of the PGE-Cu-Ni sulphide
mineralization, but also establishing the metallogenic potential of the Nipissing Gabbro
and East Bull Lake suite of intrusions to host economic accumulations of PGE. The
current study has shown that the magmas which fed the Nipissing Gabbro intrusions and
the River Valley intrusion of the East Bull Lake suite exhibit similar geochemical
characteristics. Of particular petrogenetic importance are the similarities in trace element
features, including:
1) strong LREE and LILE enrichment, a narrow range in La/Yb, and modest positive
to negative Eu anomalies;
2) high Th/Yb (2 to 10 times primitive mantle), La/Sm and Th/Nb values;
3) pronounced negative Nb, Ta and P2O5 anomalies, and in many cases negative Ti;
4) negative anomalies of Nb that are much stronger than those of Ta; and,
5) unusually low Nb/Ta and Zr/Sm compositions.
These are all features of a magma that has interacted with a crustal reservoir (Brügmann
et al., 1993; Lightfoot and Keays, 2004). These magmas also share similar characteristics
in terms of their chalcophile elements, including:
1) anomalously high background compositions for PGE relative to normal mafic
rocks;
2) good correlation between the individual chalcophile elements indicating strong
sulphide control on the PGE;
3) chondrite-normalized PGE patterns consistent with known magmatic sulphides;
and,
4) Se-Pd and Pd-Cu values that are consistent with both S-undersaturated, PGE-un
depleted continental flood basalt (CFB) magmas, second stage boninite magmas,
and PGE-enriched “pregnant” magmas.
430
Although it is recognized that the sulphide present in these intrusions has been subjected
to varying amounts of hydrothermal (deuteric) redistribution, the evidence clearly
indicates that the sulphides found in both the River Valley intrusion and the Nipissing
Gabbro suite are magmatic in origin.
It is apparent from the chalcophile element data (i.e. Pt, Pd, Cu, S, Se) that the
parental magmas which formed the River Valley intrusion and Nipissing Gabbro suite
intrusions were S-undersaturated and PGE-fertile or “pregnant” (Hamlyn and Keays,
1988; Keays et al., 2002; Keays et al., 2004) as described by Peck et al. (2001) for the
East Bull Lake intrusion. These parent magmas must have transported PGE-rich
sulphides into the River Valley and Nipissing Gabbro magma chambers. This is
especially evident from the anomalously high background concentrations of PGE which
are recorded in the unmineralized rocks from the River Valley intrusion (22 ppb Pt, 19
ppb Pd, 70 ppm Cu, 97 ppm Ni) and the Nipissing Gabbro intrusions (12.4 ppb Pt, 20.5
ppb Pd, 91 ppm Cu, 149 ppm Ni). These concentrations are orders of magnitude higher
than MORB, and closer to concentrations recorded from second-stage and boninitic
magmas (Hamlyn and Keays, 1986; Peck et al., 1992), Siliceous High Magnesium
magmas (Sun et al., 1991; Seitz and Keays, 1997) and CFB (Brügmann et al., 1993;
Momme et al., 2002b; Lightfoot and Keays, 2004).
7.2 Parental Magmas and Contamination
S-undersaturated magmas such as boninites and Siliceous High Magnesium Basalt
(SHMB) magmas have been proposed as the most likely candidates for producing fertile
intrusions in terms of PGE concentrations (Hickey and Frey, 1982; Hamlyn et al., 1985;
Hamlyn and Keays, 1986; Keays, 1982, 1995; Seitz and Keays, 1997; Sun et al., 1991).
Distinctive geochemical features of these rocks include (Piercey et al., 2001; Crawford et
al., 1989): 1) high MgO (>10 wt%), Mg-number (≥60), and Al2O3/TiO2 ratios (>35); 2)
low TiO2 (<0.5 wt%); 3) intermediate SiO2 compositions (≥53 wt%); 4) moderate to
strong U-shaped REE patterns; 5) pronounced negative HFSE anomalies (i.e. Nb, Ta, Ti);
and, 6) variable enrichment in LREE, Zr, Rb, Sr, Ba and alkali elements. These
geochemical characteristics are considered evidence that these magmas are second-stage
melts (or even multistage) derived by partial melting of a severely depleted upper mantle
which has been metasomatically enriched as a result of hydrous fluid migration within a
431
subduction zone environment (Hickey and Frey, 1982; Crawford et al., 1989; Peck et al.,
1992). Of particular importance to ore genesis is the second-stage nature of these
magmas which results in sulphides with higher PGE compositions, relative to those
magmas generated by first-stage melts (Hamlyn and Keays, 1986; Keays, 1995).
Primitive mantle-normalized multi-element diagrams, provided in Figure 7-1,
compare the REE and trace element patterns for estimated parental magmas from the
River Valley intrusion (average Layered Units) and Nipissing Gabbro intrusions (average
chilled margin gabbro) with average compositions from N-MORB, E-MORB, boninite
and uncontaminated and heavily contaminated continental flood basalts from the Siberian
Trap. The overall LILE and REE patterns from the River Valley and Nipissing Gabbro
averages are remarkably similar, suggesting similar petrogenesis of the magmas. The
patterns of elevated LILE and LREE, along with the relative depletions in Nb, Ta, P
(wt% P2O5) and Ti (wt% TiO2) for the River Valley and Nipissing Gabbro averages
closely resemble the pattern of heavily contaminated CFB (Fig. 7-1a), contrasting the
patterns of boninite, N-MORB, E-MORB, and uncontaminated CFB. The Siberian Trap
CFB are much more contaminated than the estimated parental magmas for the River
Valley intrusion and Nipissing Gabbro intrusions and this is reflected in their elevated
LILE and REE compositions (Fig. 7-1). Normalizing the average River Valley and
Nipissing Gabbro values against heavily contaminated CFB results in near-flat but saw-
tooth patterns that are slightly less than 1; the pronounced Sr anomaly is probably due to
cumulus plagioclase. These normalized patterns suggest that the estimated parental
magmas to the River Valley and Nipissing Gabbro intrusions were contaminated CFB;
the <1 normalized values reflect the exceptionally contaminated nature of the Siberian
Trap CFB as compared to the River Valley and Nipissing Gabbro parental magmas (Fig.
7-1b).
Some CFB lavas such as those of East Greenland and most of the Siberian Traps,
have high PGE contents and were formed from S-undersaturated and PGE-undepleted
magmas (Brügmann et al., 1993; Momme et al, 2002b; Lightfoot and Keays, 2004).
432
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P Sm Zr Ti Tb Y Er Yb
Roc
k/Pr
imiti
ve M
antle
Nipissing Gabbro - Parental MagmaRiver Valley LU - Parental MagmaSiberian Trap - contaminated CFBSiberian Trap - uncontaminatedBoninite - Subduction ZoneN-MORBE-MORB
(A)
Figure 7-1a. Primitive mantle-normalized multi-element diagram comparing estimates of
parental magma compositions for the River Valley intrusion (average Layered Unit) and
Nipissing Gabbro intrusions (average chilled margin gabbro) with heavily contaminated
and uncontaminated Siberian Trap CFB, boninite, N-MORB and E-MORB. Data for N-
MORB is from Fitton et al. (2000); data for E-MORB (Moana Loa) is from Crawford and
Keays (unpublished data); data for boninite is from Crawford and Keays (unpublished
data); data for contaminated and uncontaminated Siberian Trap CFB (Nadezhinsky
Formation) is from Lightfoot and Keays (2004). Normalizing primitive mantle values are
from McDonough and Sun (1995).
433
0.01
0.1
1
10
100
Rb Th K* Nb Ta La Ce Sr Nd P Sm Zr Ti Tb Y Er Yb
Roc
k/Pr
imiti
ve M
antle
Nipissing Gabbro - Parental Magma
River Valley LU - Parental Magma
Siberian Trap - contaminated CFB
Nipissing/Siberian Trap (contaminated CFB)
River Valley LU/Siberian Trap (contaminated CFB)
Normalized to Contaminated CFB
(B)
Figure 7-1b. Primitive mantle-normalized multi-element diagram comparing estimates of
parental magma compositions for the River Valley intrusion (average Layered Unit) and
Nipissing Gabbro intrusions (average chilled margin gabbro) with heavily contaminated
Siberian Trap CFB. The estimates of parental magma compositions for the River Valley
intrusion and Nipissing Gabbro intrusions are normalized to heavily contaminated
Siberian Trap CFB resulting in a saw-tooth pattern that is slightly <1. Data for N-MORB
is from Fitton et al. (2000); data for E-MORB (Moana Loa) is from Crawford and Keays
(unpublished data); data for boninite is from Crawford and Keays (unpublished data);
data for contaminated and uncontaminated Siberian Trap CFB (Nadezhinsky Formation)
is from Lightfoot and Keays (2004). Normalizing primitive mantle values are from
McDonough and Sun (1995).
434
The high PGE contents of these lavas poses a yet unresolved problem as traditional
mantle melting models predict that the formation of PGE-undepleted magmas requires a
minimum of 25% partial melting (Lightfoot and Keays, 2004) whereas the REE predict,
for example, that the some of the East Greenland CFB were formed by as little as 5%
partial melting (Tegner et al., 1998).
Momme et al. (2002c) attempted to explain the high PGE contents of the plume-
generated CFB in Iceland with the “Triangular Melting Regime” model. This model,
originally developed by Langmuir et al. (1992) to explain the generation of magmas at
spreading ridges, invokes a melting regime beneath a continental rift that is “triangular”
in form and governed by magma upwelling (ascending mantle plume) and corner flow
(asthenospheric mantle flow) that is perpendicular to the vertical rise of the mantle
plume. The melting regime essentially produces several different melt types from which
to draw parental magmas (Momme et al., 2002b): (1) in the asthenosphere (~120 km
depth), low degrees of melting from the lower “corners” of the upwelling melt triangle
results in high (La/Sm)N, low PGE content, and S-saturated (olivine tholeiite) melts; (2)
at the top of the melting column (~60 km depth) high degrees of melting from the upper
“point” of the upwelling melt triangle (near the top of the asthenosphere/base of the
lithospheric mantle) results in low (La/Sm)N, high PGE content, and S-undersaturated
(picrite) melts; and, (3) within the lower lithospheric mantle, intermediate degrees of
melting result in an ascending melt that has intermediate (La/Sm)N and PGE content. In
applying the Triangular Melting Regime model to Iceland, Momme et al. (2002c)
demonstrated that PGE-undepleted and S-undersaturated magmas can be generated by
11-12% partial melting of a mantle plume.
Lightfoot and Keays (2004), argued that the Triangular Melting Regime model does
not adequately explain the PGE-undepleted nature of those CFB basalts in East
Greenland and Siberia whose REE contents suggest even lower degrees of partial
melting. Alternatively, Lightfoot and Keays (2004), proposed that the Siberian Trap
magmas were formed by the interaction of high MgO (picritic?) magmas, sourced from a
mantle plume, with lithospheric mantle from which S-saturated first-stage melts (MORB-
type magmas) had already been extracted. This lithospheric mantle would have been
depleted in the incompatible elements and in particular, would have been strongly
435
depleted in S, but enriched somewhat in PGE; the PGE would have been retained in the
residual sulphides left behind in the refractory residue as a result of partial melting (i.e. a
source for a second-stage melt). Interaction of the depleted lithospheric mantle with the
plume-sourced picritic melts would have produced a S-undersaturated and PGE-
undepleted (second-stage) magma. It is possible that the plume-sourced high MgO melt
was an alkali picrite or a maymechite (very Mg-rich alkaline volcanic rock), which are
subordinate but important rock types in the Siberian Trap (Arndt et al., 1998).
The current study has demonstrated that unmineralized rocks from the Layered Units
in the River Valley intrusion and most rocks from the Nipissing Gabbro suite exhibit
geochemical homogeneity that can only be accounted for by invoking a single source for
their respective magmas. Of particular note is the consistency in the geochemistry of the
rocks from the Nipissing Gabbro intrusions, which were collected from seventeen
different intrusions with an extensive geographic distribution (Fig. 1-2). Both suites of
rocks also exhibit evidence for significant but reasonably uniform contamination of
mantle-derived magmas, suggesting that the crustal contamination occurred in either a
single large staging chamber or in a section of the crust that had a uniform composition.
Lithogeochemical studies (Conrod, 1988; Lightfoot and Naldrett, 1989) on Nipissing
Gabbro sills have shown that compositional variances in individual intrusions are
reflective of AFC processes, whereby strong in-situ differentiation was coupled with
contamination of the magmas by assimilation of local country rocks. However, these
authors also point out that the contamination signature that is common and consistent
throughout the Nipissing Gabbro intrusions is not related to local contamination but
rather to earlier bulk contamination of the magmas at their source. If the contamination
signatures observed in all the intrusions were due to the assimilation of local lithologies
then one would expect a much wider variation in their composition. Lightfoot and
Naldrett (1989) and Lightfoot et al. (1986, 1987, 1993), primarily on the basis of
geochemical evidence, argued convincingly that the Nipissing Gabbro intrusions
represent the intrusive roots of an eroded continental flood basalt. This magmatic
association would explain the pervasive contamination signature found in nearly all
Nipissing Gabbro rocks and supports the premise for a staging chamber within the
underlying continental crust at mid-crustal levels.
436
7.3 Pregnant Magmas
The term “pregnant magmas” was coined by Hamlyn and Keays (1988) to describe
magmas which had carried sulphides formed in one environment, into the resident
magma chambers of PGE-bearing layered mafic/ultramafic intrusions. These authors
devised the term to describe the processes by which PGE mineralization had formed in
the Panton Sill, located in Western Australia (Hamlyn and Keays, 1979). Basically,
pregnant magmas are formed where parental magmas became S-saturated in “staging
chambers” below the final site of mineralization and/or in the conduits that lead into the
intrusions in which the PGE mineralization is currently found. Although the term was
coined to describe platiniferous horizons in layered intrusions, it is equally applicable to
those deposits in which the ore-forming sulphide melts were carried into the magma
chamber. Excellent examples of pregnant magmas are those that formed the giant
Noril’sk-Talnahk deposits (Brügmann et al., 1993; Lightfoot and Keays, 2004) and the
Voisey’s Bay Ni-Cu-Co sulphide deposits (Naldrett et al., 2000). In both of these
examples, Ni-Cu-PGE sulphide melts are believe to have formed at depth in staging
chambers in which primitive mantle-derived magmas became S-saturated and segregated
Ni-Cu-PGE sulphide liquids due to interaction with mid-crustal rocks. The sulphides
were subsequently carried into their current settings by possibly more primitive and
dynamic magmas which were able to entrain the sulphides, and rock fragments in the
case of Voisey’s Bay, and carry them upwards. The sulphides (and rock fragments) were
deposited when the velocity of the carrier magmas decreased on passing from the magma
conduits into larger chambers. Peck et al. (2001) applied this model to the contact
sulphides in the East Bull Lake Intrusion, arguing that the sulphides had formed at depth
and been carried into the East Bull Lake intrusion as entrained droplets of Ni-Cu-PGE
sulphides. The concept of pregnant magmas is also applicable to the River Valley
intrusion; such a magma could not only have transported the PGE-rich sulphides into the
chamber but also the many xenolith fragments observed in the Breccia Unit of the
Marginal Series. Although the magmas that formed the Nipissing Gabbro suite share
many similarities with the River Valley magmas, they appear to have not been pregnant
magmas but rather their sulphides were dissolved in the parental magmas (probably
437
during ascent through the crust), precipitating in-situ (and early-on), during normal
fractionation and cooling of the S-undersaturated silicate magma.
7.4 Genetic Model
There are three principal mechanisms of contamination which may lead to S-
saturation and the precipitation of sulphide (Keays, 1995): 1) the addition of external S
by means of devolitization, partial melting, or bulk assimilation of the S-bearing country
rock; 2) an increase in fO2, leading to a lowering of the FeO content and a reduction in
the S carrying capacity of the magma; and, 3) addition of external silica by assimilation
of siliceous partial melts (assimilation of country rocks or continental lithosphere)
thereby lowering the S solubility of the magma. Perhaps the most important ore-forming
mechanism that has been recognized in many large magmatic PGE-Cu-Ni sulphide
deposits is crustal contamination (e.g. Noril’sk deposits, Li et al.,2003; Duluth Complex,
Theriault et al., 2000; Muskox, Barnes and Francis, 1995; Bushveld Complex, Cawthorn,
1999). Geochemical signatures for magmas from modern subduction zones are
characterized by a mantle source that has been enriched in LILE (i.e. Cs, K, Rb, Sr, Ba),
Th, and commonly by enrichment in LREE (i.e. La, Ce), with relative depletion in HFSE
(i.e. Nb, Ta, Zr, Ti) (Pearce and Norry, 1979; Pearce and Cann, 1993). In contrast,
continental crust assimilation is minimized in oceanic settings, leading to enrichments in
LILE, Th and LREE that are more clearly ascribed to an enriched mantle source (Sun and
Nesbitt, 1978). Of particular significance, however, is that similar signatures can also be
acquired in non-subduction zone settings, such as CFB, through the assimilation of crust
(Sun and McDonough, 1989; Smithies et al., 2004).
Rocks from the Nipissing Gabbro and River Valley intrusions have a distinct crustal
signature, expressed by the relative enrichment in highly incompatible trace elements and
relative depletion in Nb, Ta, and Ti (Fig. 7-1). Geographically, this crustal signature is
pervasive and relatively homogeneous across all of the areas sampled which suggests that
it is not derived from local country rocks but rather from a deeper source. Moreover, the
current study has shown that PGE-rich sulphide mineralization in the fragments and
matrix rocks of the BX from the River Valley intrusion is unrelated to processes within
the present intrusion, but rather that the ore-forming processes were initiated much
earlier. A staging chamber, located at some depth in the crust, is invoked to explain the
438
trends noted in the chalcophile and trace elements. The idea of a staging chambers to
explain the extensive crustal contamination signatures and argue against subduction-zone
related magmatism, is noted in other large mafic intrusions. For example, it is largely
accepted that the crustal signature in the Bushveld Complex was acquired by
contamination, both in a lower staging chamber and during ascent of the magmas through
the Kaapvaal crust, rather than during melting of enriched sub-continental lithosphere
(Schiffries and Rye, 1989; Maier et al., 2000). Other examples that invoke assimilation
of crust and the formation of sulphides in a deep-seated staging magma chamber, as
suggested for the East Bull Lake intrusion (Peck et al., 2001) and for other rocks
(Portimo Complex, Iljina and Hanski (2002); Siberian Trap flood basalts, Arndt et al.,
1998; Voisey’s Bay, Naldrett et al., 2000; mafic intrusions, Thompson and Naldrett,
1984).
The striking similarities in magma composition between the two suites, and evidence
for considerable, and potentially economic, accumulations of PGE-Cu-Ni sulphide,
evokes the conclusion that these magma have similar sources and that the sulphides were
subjected to initially similar ore-forming mechanisms, even though their respective
magmatic events are separated by more than 250 Ma. A model to explain the genesis of
the PGE-fertile magmas of the River Valley intrusion and the Nipissing Gabbro suite is
suggested in the context of a mantle plume related, intra-cratonic rift which is widely
accepted to have existed in the region, more or less between ~2.5 and ~2.2 Ga. This does
not imply that a single extremely long-lived (>200 Ma) mantle-plume was responsible for
both of the magmatic events but rather accepts the notion that multi-generations of
mantle plume activity may have been present, with punctuated magmatic activity at ~2.48
Ga and 2~2.2 Ga. Any petrogenetic model must address the elevated PGE concentrations
in the parental magmas, the transport mechanism of the PGE, and the PGE concentration
mechanism(s). The current magmatic model, which is generally applicable to both the
River Valley and Nipissing Gabbro magmas, addresses these parameters, invoking the
development of one or more deep-seated crustal staging chamber(s), and summarized in
Figure 7-2. In the case of the Nipissing Gabbro suite, an alternative model relating to the
source and emplacement mechanism for the parental magmas, as proposed by Buchan et
al. (1998), should be noted. These authors suggest that the Nipissing Gabbro magmas
439
may have been introduced by means of laterally flowing magmas, fed into the region
through the Senneterre Dyke Swarm (see Section 3.4). This model would preclude the
presence of a staging chamber for the Nipissing Gabbro suite in the Sudbury region and
could possibly account for the crustal contamination signature and low R factors of the
magmas. However, assessing the merits of such a model is beyond the scope of this
study.
The first stage of the magmatic model (Fig. 7-2a) is applicable to both the River
Valley and Nipissing Gabbro magmas. Within the respective staging chambers, the S-
undersaturated, primitive mantle-derived magma interacted with crustal lithologies and
introduced crustal S into the magma. The assimilation of crustal material, as indicated by
the crustal trace element and LREE signatures, induced S-saturation and segregation of
PGE-rich sulphides. Assimilation, fractionation and crystallization of the magma (i.e.
AFC processes) would have led to chamber stratification, resulting in the development of
a buoyant feldspathic liquid that rose toward the upper part of the staging chamber, and a
more dense and mafic (ferromagnesian-rich) liquid that settled toward the lower part of
the chamber. The early-formed silicates would have produced mafic (olivine-
orthopyroxene) cumulates and/or chilled phases which are today represented in the River
Valley intrusion by the fine-grained mafic xenoliths in the Breccia Unit; the lack of
olivine-bearing rocks in the Nipissing Gabbro suite also supports such a process. It is
likely that the PGE-rich sulphides observed in the River Valley breccia fragments were
incorporated into the cumulates at this stage. It is important to note that the fragments in
the Breccia Unit are interpreted to have been cumulates and that they are extremely
altered with no textural evidence (i.e. relict textures) to unequivocally identify them as
cumulates; alternatively they could represent chilled margin gabbro and/or pyroxenite
which crystallized early on within the staging chamber.
The second stage of the magmatic model (Fig. 7-2b) is applicable to both the River
Valley and Nipissing Gabbro magmas and their respective staging chambers. As
additional S-undersaturated magma flowed into the staging chamber it would have mixed
with the resident S-saturated magma resulting in the upgrading of PGE tenor in the
resident sulphides (varying R factors) and further segregation of sulphides. The newly
introduced magma would have also displaced some of the modified, S-saturated, PGE-
440
rich sulphide laden magmas out of the staging chamber. The evacuating magmas would
have entrained mafic fragments, derived from early formed cumulates and/or chilled
margin, and PGE-rich sulphide droplets; the sulphide droplets would have continued to
interact with the surrounding silicate liquid upgrading their PGE tenor. In the case of the
River Valley intrusion, these displaced magmas would eventually form the PGE-rich
sulphides that occur in the matrix of the Breccia Unit.
Figure 7-2a. Staging Chamber: S-undersaturated, primitive mantle-derived magmas rise
and form staging chambers at mid-crustal levels. Cooling and crustal contamination
(sulphur source) induces S-saturation and sulphide segregation in the resident magma.
Crystallization and chamber stratification results in a buoyant feldspathic liquid overlying
a more dense mafic liquid. PGE-bearing sulphides form under varying R factors, some
sink and are incorporated into the early formed chilled margin rocks and/or olivine-
orthopyroxene dominated cumulates.
441
In the third stage of the magmatic model, the sulphide (PGE-rich droplets) and
fragment bearing magmas are displaced from the staging chamber and rise through the
crust (Fig. 7-2c). Rapid ascent of the magmas through the crust would have resulted in
adiabatic decompression of the magmas which permitted some or all of the sulphur from
the sulphide melt to be partially or wholly dissolved into the magma. In the case of the
River Valley magmas, the PGE-rich sulphide droplets remained suspended in the S-
saturated magmas and only a small portion of the sulphur from the sulphide melts
(droplets) dissolved into the magma. This, coupled with further interaction between the
silicate liquid and the sulphide droplets, resulted in substantial upgrade of the PGE tenor
in the sulphides. During their ascent, the Nipissing Gabbro magmas became S-
undersaturated and all of the sulphur was dissolved into the magma. The presence of
mafic fragments in the River Valley magmas (Breccia Unit) suggests a very dynamic
magma system, capable of entraining and supporting the fragments as the magmas
ascended through the conduit(s) in the crust. Evidence for this dynamic (turbulent)
magma is accounted for by the high R factors and elevated PGE tenor in the River Valley
intrusion relative to the Nipissing Gabbro suite. The rarity of fragments in the Nipissing
Gabbro suite can be accounted for by lower magma dynamics, as reflected by the low R
factors and relatively low PGE tenor, which resulted in the fragments being “filtered” out
of the ascending magmas. Alternatively, the Nipissing Gabbro magmas may have never
picked up any fragments or the conduits may have been too narrow to allow for the
fragments to be entrained into the final intrusions. Orthopyroxene phenocrysts, common
in nearly all of the Nipissing Gabbro bodies, were either entrained in the ascending
magmas and/or crystallized within the conduit(s) as the magmas ascended through the
crust.
During the final fourth stage of the magmatic model, the magmas were emplaced
into their final magma chambers, where they underwent two very different processes
(Fig. 7-2d). The River Valley magmas, which were S-saturated and “pregnant” with
PGE-rich sulphide droplets, co-precipitated with the silicate minerals that now constitute
the matrix of the Breccia Unit. Convective flow within the magma allowed for further
interaction between the PGE-rich sulphide droplets and the silicate liquid (even higher R
factors), further upgrading the PGE tenor of the sulphides.
442
Figure 7-2b. Displacement: New S-undersaturated, primitive mantle-derived magma
enters the staging chamber and mix with the S-saturated resident magma. The magma
mixing upgrades the PGE tenor in the sulphides under varying R factors. The new
magma also forces the modified, S-saturated, PGE-rich sulphide laden magmas out of the
respective staging chambers. Evacuating magmas entrain mafic fragments derived from
early formed cumulates and/or chilled margin, and PGE-rich sulphide droplets which
continue to interact with the surrounding silicate liquid; these transporting magmas form
the PGE-rich matrix of the Breccia Unit in the River Valley Intrusion.
443
Figure 7-2c. Ascent: Displaced magmas, containing PGE-rich sulphide droplets and
fragments, undergo adiabatic decompression permitting some or all of the sulphur from
the sulphide melt to be partially or wholly dissolved into the ascending magma. The
ascending River Valley magmas remain S-saturated and only a small portion of the
sulphur from the sulphide melts is dissolved into the magma, upgrading the PGE tenor of
the sulphide droplets. The ascending Nipissing Gabbro magmas become S-undersaturated
and all of the sulphur is dissolved into the magma. The presence of mafic fragments in
the River Valley magmas (Breccia Unit) suggests a very dynamic magma system which
accounts for the higher R factors and PGE tenor in the River Valley intrusion relative to
the Nipissing Gabbro suite. Fragments are rare in the Nipissing Gabbro suite and this can
be accounted for by lower magma dynamics, as signified by low R factors, resulting in
the fragments being “filtered” out of the ascending magmas.
444
Figure 7-2d. Emplacement: River Valley magmas form the River Valley intrusion
chamber at upper crustal depths (8-12 km). These magmas, which are S-saturated and
“pregnant” with PGE-rich sulphide droplets, co-precipitate with the silicate minerals that
now constitute the matrix of the Breccia Unit. Convective flow within the magma allows
for further interaction between the PGE-rich sulphide droplets and the silicate liquid,
further upgrading the PGE tenor of the sulphides. Nipissing Gabbro magmas, which are
PGE-fertile and S-undersaturated, are emplaced at various levels within the Huronian
Supergroup sedimentary rock sequences. As the magmas cool and crystallize, they
become S-saturated and begin to segregate PGE-rich sulphides, principally within the
massive orthopyroxene gabbro unit within the lower portions of the bodies. The
geochemical characteristics of the River Valley and Nipissing Gabbro suite magmas and
the tectonic setting in which the magmas developed and were emplaced, suggests that
both magmas may have fed continental flood basalts.
445
Significantly, there is almost as much sulphide in the fragments as there is in the matrix;
a similar result is reported Brügmann et al. (1993) for rocks in the Noril’sk region.
Nipissing Gabbro magmas, which at the time of emplacement were PGE-fertile and S-
undersaturated, were emplaced in various forms and at various levels within the Huronian
Supergroup sedimentary rock sequences. As these magmas cooled and crystallized, they
became S-saturated and segregated PGE-rich sulphides through normal fractionation,
principally within the massive orthopyroxene gabbro unit located in the lower portions of
the intrusions.
It is probable that the processes outlined in stages two through four of the magmatic
model would have repeated themselves several times, introducing new batches of magma
into some of the Nipissing Gabbro intrusions and the River Valley intrusion. The
Nipissing Gabbro magmatic event is thought to have spanned a period of about 15 Ma
and Lightfoot and Naldrett (1996) reported evidence for multiple pulses of magma in
some Nipissing Gabbro intrusions. In the River Valley intrusion, field and geochemical
evidence (e.g. stoping of the overlying Layered Units in the Inclusion-bearing Unit and
the distinct PGE-enrichment in the Breccia Unit) suggests that the Marginal Series rocks
represent at least a “second” batch of magma that was introduced into the River Valley
chamber subsequent to crystallization of the bulk of the intrusion (i.e. upper Layered
Units). Although evidence for multiple magma pulses within the Marginal Series’
Breccia Unit itself has yet to be established it is probable that several pulses of PGE-rich
sulphide laden magma were involved.
7.5 Implications to Mineral Exploration
Currently, no economic sulphide deposits have been outlined in either the East Bull
Lake suite intrusions or those of the Nipissing Gabbro suite. However, exploration work
completed to date appears to hold a great deal of promise for the Marginal Series rocks in
the River Valley intrusion, as well as in other East Bull Lake suite intrusions (i.e. East
Bull Lake and Agnew Lake intrusions), and in the stratabound PGE-rich sulphide
mineralization in several Nipissing Gabbro intrusions (e.g. Rastall Occurrence in the
Chiniguchi River intrusion (Janes Township) and the Shakespeare Deposit (Shakespeare
Township).
446
In terms of prospectivity and the potential for economic PGE-Cu-Ni sulphide
deposits, the Nipissing Gabbro intrusions show tremendous possibility. In addition to
confirming that this suite of intrusions indeed have very high background PGE
concentrations, this study demonstrated that many of the Nipissing Gabbro rocks have
very low PGE contents relative to chilled margin, suggesting that the magma(s) became
S-saturated during in-situ fractionation and therefore deposited PGE-bearing sulphides
somewhere in the magma chamber. The bigger question in terms of exploration in these
intrusions is where are these PGE-rich sulphides? Also of significant importance is the
widespread occurrence of this intrusive suite in the Southern Province, the multitude of
mineral occurrences associated with them, and the large volume of magma that is
expected to have moved through the system (Lightfoot and Naldrett, 1996). However,
individual intrusions of Nipissing Gabbro are generally small when compared to those of
the East Bull Lake suite or other classic magmatic sulphide bearing intrusions (i.e.
Muskox, Stillwater, Bushveld), and it is because of this that relatively little exploration
work has focused on magmatic sulphides in these intrusions. Rice (1997), in modelling
the physics of convecting magmas, resolved that economically interesting stratiform PGE
deposits would be restricted to large magma bodies; the smaller the magma chamber, the
thinner the layers and therefore a lower probability of high R factors. On this basis, and
in the context of the typical size of a Nipissing Gabbro body, these intrusions are
considered too small to be of any consequence in terms of generating economic PGE
deposits, despite the fact that Nipissing Gabbro suite intrusions are known to host
stratabound PGE-Cu-Ni mineralization (e.g. Rastall occurrence). It should therefore, be
pointed out that the Konttijarvi body in the Portimo Complex is a relatively small
intrusion (present-day volume of ~0.05 km3; Iljina, 1994) yet it is host to a multi-million
ounce PGE deposit. By comparison, the Chiniguchi River intrusion is estimated to have
a present-day (minimum) volume of ~2 km3, and sills such as the Kukagami Lake
intrusion have estimated present-day volumes of ~0.5 km3. The significance of this is
that the small size of a mafic body does not necessarily make it non-prospective and that
the specific characteristics of the intrusion (i.e. intrusion geometry, magma source
(geochemistry/genesis), R factors, volume of magma introduced), interpreted in the
447
context of the larger tectonic environment, are perhaps of greater significance in mineral
exploration.
The potential for discovery (delineation) of an economic PGE-Cu-Ni deposit or
deposits in the River Valley and East Bull Lake intrusions is promising, especially when
considering their size and the fact that mineral exploration to date has not been very
extensive and/or systematic. An important concept in the exploration for contact-type
PGE deposits is that they are in general analogous to the low-grade, large tonnage Cu-Au
rich porphyry models; a particularly important concept to grasp in the exploration and
economic evaluation of contact-type PGE mineralization. In Canada, there is only one
primary producer of PGE (Pt-Pd), the Lac des Iles mine (Lac des Iles Complex) located
about 100 km north of Thunder Bay, Ontario. The Measured and Indicated resources of
this producing mine total over 145 million tonnes grading 1.57g/t Pd, 0.17g/t Pt, 0.12g/t
Au, 0.06% Cu and 0.05% Ni (North American Palladium Ltd., Press Release, March 5th,
2001). The Konttijarvi and Ahmavaara mineralised zones in the Konttijarvi-Suhanko
intrusion of the Portimo Complex, Finland are direct analogues to the geology and
mineralization described for the East Bull Lake suite and Nipissing Gabbro intrusions
(Vogel et al., 1998b). Gold Fields Limited reported (Press Release, July 23rd, 2001) that
the Konttijarvi deposit contains a Measured, Indicated and Inferred resource of over 43
million tonnes grading 1.42 g/t Pd, 0.39 g/t Pt, 0.1 g/t Au, 0.15% Cu and 0.06% Ni,
including a Measured resource of 11.7 million tonnes grading 1.6 g/t Pd, 0.43 g/t Pt, 0.1
g/t Au, 0.15% Cu and 0.07% Ni (0.5 g/t Pd-Pt-Au cut-off grade). Also in the Portimo
Complex, the Ahmavaara deposit has a reported Measured, Indicated and Inferred
resource of over 74 million tonnes grading 1.05 g/t Pd, 0.22 g/t Pt, 0.12 g/t Au, 0.21% Cu
and 0.09% Ni, including a Measured resource of 11.8 million tonnes grading 1.02 g/t Pd,
0.19 g/t Pt, 0.1 g/t Au, 0.21% Cu and 0.09% Ni. These “real world” examples indicate
that a bulk-tonnage, low-grade PGE operation is possible and it is expected that potential
economic contact-type PGE mineralization may require a minimum 20-50 million tonnes
at grades >2.0 g/t PGE, bearing in mind that these estimates are highly dependent on
commodity prices.
448
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473
APPENDIX 1:
SPECIMEN DESCRIPTIONS, WHOLE-ROCK AND CIPW DATA
A) Lower Limits of Detection 474
B) Analytical Method Codes and Explanatory Notes 476
C) Nipissing Gabbro Intrusions – Geochemical Data 477
D) Nipissing Gabbro Intrusions - CIPW Normative Calculations 501
E) River Valley Intrusion - Matrix and Fragment Geochemical Data 523
F) River Valley Intrusion – CIPW Normative Calculations 527
G) River Valley Intrusion – Group-1 Data (RV00-22 core samples) 530
H) River Valley Intrusion – Group-2 Data (RV00-22 core samples) 534
474
(A) LOWER LIMITS OF DETECTION
Laboratory
Element Unit Method* Geo Labs Accurassay ACTLABS Chemex XRAL
SiO2 wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 TiO2 wt% WD-XRF 0.01 0.001 0.005 0.01 0.01 Al2O3 wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 Fe2O3 wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 MnO wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 CaO wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 MgO wt% WD-XRF 0.01 0.01 0.01 0.01 0.01 Na2O wt% WD-XRF 0.01 0.02 0.01 0.01 0.01 K2O wt% WD-XRF 0.01 0.02 0.01 0.01 0.01 P2O5 wt% WD-XRF 0.01 0.02 0.01 0.01 0.01 LOI wt% WD-XRF 0.05 0.01 0.01 0.01 0.01 Be ppm ICP-AES 3 0.1 1 0.1 0.5 Co ppm ICP-AES 5 1 1 1 1 Cu ppm ICP-AES 5 1 1 1 0.5 Mo ppm ICP-AES 8 1 5 1 1 Ni ppm ICP-AES 5 1 1 1 1 Sc ppm ICP-AES 1 na 0.1 0.5 0.5 Sr ppm ICP-AES 1 1 2 1 0.5 V ppm ICP-AES 5 1 5 5 2 W ppm ICP-AES 40 1 3 2 10 Zn ppm ICP-AES 2 1 1 1 0.5 Cr ppm ICP-MS 1 1 1 2 1 La ppm ICP-MS 0.01 na 0.05 0.5 0.1 Ce ppm ICP-MS 0.01 na 1 0.5 0.1 Pr ppm ICP-MS 0.01 na 0.02 0.1 0.2 Nd ppm ICP-MS 0.01 na 1 0.5 0.1 Sm ppm ICP-MS 0.01 na 0.01 0.1 0.1 Eu ppm ICP-MS 0.01 na 0.05 0.1 0.05 Gd ppm ICP-MS 0.01 na 0.02 0.1 0.1 Tb ppm ICP-MS 0.01 na 0.1 0.1 0.1 Dy ppm ICP-MS 0.01 na 0.02 0.1 0.1 Ho ppm ICP-MS 0.01 na 0.01 0.1 0.05 Er ppm ICP-MS 0.01 na 0.01 0.1 0.1 Tm ppm ICP-MS 0.01 na 0.005 0.1 0.1 Yb ppm ICP-MS 0.01 na 0.05 0.1 0.1 Lu ppm ICP-MS 0.01 na 0.01 0.1 0.05
*WD-XRF = Wavelength Dispersive - X-Ray Fluorescence; ICP = inductively coupled plasma; AES = atomic emission spectroscopy; MS = mass spectrometry; AAS = atomic absorption spectrometry; FA = fire assay; † = average limit of detection; na = not applicable
475
Laboratory
Element Unit Method* Geo Labs Accurassay ACTLABS Chemex XRAL
Rb ppm ICP-MS 0.01 na 2 0.2 2 Sr ppm ICP-MS 0.02 na 2 0.1 2 Nb ppm ICP-MS 0.02 na 2 1 2 Cs ppm ICP-MS 0.01 na 0.2 0.1 1 Hf ppm ICP-MS 0.01 na 0.2 1 1 Ta ppm ICP-MS 0.01 na 0.3 0.5 1 Th ppm ICP-MS 0.02 na 0.1 1 0.1 U ppm ICP-MS 0.02 na 0.1 0.5 0.1 Y ppm ICP-MS 0.5 na 1 0.5 1 Zr ppm ICP-MS 1 na 4 0.5 2 Se ppb AAS 7 100 200 200 100 S wt% L-IR 0.01 0.01 0.01 0.01 0.01
Os ppb FA/ICP-MS Na na 2 na 3 Ir ppb FA/ICP-MS †0.27 na 0.1 na 0.1
Ru ppb FA/ICP-MS †0.66 na 5 na 1 Re ppb FA/ICP-MS Na na 5 na 1 Rh ppb FA/ICP-MS †0.26 na 0.2 30 30 Pt ppb FA/ICP-MS †1.43 15 5 5 10 Pd ppb FA/ICP-MS †1.88 10 2-4 2 1 Au ppb FA/ICP-MS †1.42 5 0.5-2 2 5 Ag ppm FA/ICP-MS 0.5 1 0.2 0.2 5
*WD-XRF = Wavelength Dispersive - X-Ray Fluorescence; ICP = inductively coupled plasma; AES = atomic emission spectroscopy; MS = mass spectrometry; AAS = atomic absorption spectrometry; FA = fire assay; † = average limit of detection; na = not applicable
476
(B) ANALYTICAL MTHOD CODES AND EXPLANATORY NOTES: 1Method: 1=WD-XRF, 2=Lebo thermogravimetry, 3=Leco infrared combustion, 4=DCP, 5=ICP-MS, 6=NiS/ICP-MS, 7=AAS-hydride, 8=Fire Assay/DCP 2Sample Type: L=massive/layered unit, M=matrix, F=fragment; b-qtz=blue quartz; Rock Type: Mgab=melagabbro, Lgab=leucogabbro, gab=gabbro 3CIPW Name: OGN=olivine gabbronorite; GN=gabbronorite; OLGN=olivine leucogabbronorite; LGN=leucogabbronorite; G=gabbro Concentrations: Major Element Oxides, S, CO2, and LOI concentrations are in wt% Trace element and Cu-Ni concentrations are in ppm PGE and Se are in ppb Miscellaneous: LLD = lower limit of detection "-" = not detected/determined Fe2O3* = total iron Ti* = calculated from TiO2P* = calculated from P2O5
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Lake
Tra
vm
g; n
o m
iner
aliz
atio
n; m
assi
vega
bbro
JB97
-28
Cle
men
tM
anito
u La
ke T
rav
mg;
no
min
eral
izat
ion;
mas
sive
gabb
roJB
97-2
9C
lem
ent
Man
itou
Lake
Tra
vm
g; n
o m
iner
aliz
atio
n; m
assi
vega
bbro
JB97
-30
Cle
men
tM
anito
u La
ke T
rav
mg;
no
min
eral
izat
ion;
mas
sive
gabb
roJB
97-3
1C
lem
ent
Man
itou
Lake
Tra
vm
g; n
o m
iner
aliz
atio
n; m
assi
vega
bbro
JB97
-32
Cle
men
tM
anito
u La
ke T
rav
mg;
no
min
eral
izat
ion;
mas
sive
gabb
roJB
97-3
3Fo
ster
Bra
zil L
ake
cpy
mai
nly
in th
e Q
-C v
ein;
po
mai
nly
in p
od-li
ke h
oste
d by
mg
Nip
. Gab
.ga
bbro
JB97
-34
Fost
erB
razi
l Lak
efg
-mg;
abo
ut 3
m n
orth
of c
liff-
sedi
men
tsga
bbro
JB97
-36
Fost
erB
razi
l Lak
em
g; ~
60 m
wes
t of t
renc
h; w
ithin
5m
of w
hite
"bu
ll" q
tz v
ein;
alte
red
gabb
roJB
97-3
9AN
airn
Nai
rn W
right
mg;
msv
. sul
phid
es in
Nip
. Gab
bro/
trenc
hes;
>80
% su
lphi
des;
blu
e qu
artz
eye
sga
bbro
JB97
-39B
Nai
rnN
airn
Wrig
htm
g; c
py a
nd p
o in
Nip
. Gab
bro
as u
p to
25%
pat
ches
; blu
e qy
artz
eye
sga
bbro
JB97
-39C
Nai
rnN
airn
Wrig
htm
g; b
lue
qtz.
eye
s up
to 2
5% o
f gab
bro;
wal
l roc
k by
tren
ch b
last
gabb
roJB
97-4
0AJa
nes
Chi
nigu
chi
mg;
S-e
dge
of o
/c; n
on-m
iner
aliz
ed(4
0B?)
; Kirk
land
Tow
nsite
Occ
.; Ja
nes S
outh
gabb
roJB
97-4
0BJa
nes
Chi
nigu
chi
mg;
mag
mat
ic-2
BA
GS;
Kirk
land
Tow
nsite
; Jan
es S
outh
gabb
roJB
97-4
1AJa
nes
Chi
nigu
chi
mg;
mag
mat
ic; e
ast e
nd o
f tre
nch;
NE
of K
irkla
nd T
owns
ite O
cc; b
y sw
amp
gabb
roJB
97-4
1BJa
nes
Chi
nigu
chi
mg;
mid
dle
of tr
ench
; NE
of K
irkla
nd T
owns
ite O
ccur
renc
e; b
y sw
amp
gabb
roJB
97-4
1CJa
nes
Chi
nigu
chi
mg;
non
-min
eral
ized
from
edg
e of
swam
p; N
E of
Kirk
land
Tow
nsite
Occ
gabb
roJB
97-4
2AJa
nes
Chi
nigu
chi
mg;
edg
e of
"pi
t" b
y sw
amp,
~35
m so
uth
of JB
97-4
1; N
E of
K.T
.Oga
bbro
JB97
-42B
Jane
sC
hini
guch
im
g; m
agm
atic
with
onl
y pa
tchy
alte
ratio
n; N
E of
Kirk
land
Tow
nsite
Occ
gabb
ro
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-65
JB97
-78B
JB97
-48
JB97
-49
JB98
-207
JB98
-224
JB98
-239
BJB
98-2
39C
JB98
-240
JB97
-4B
JB97
-18
JB97
-20
JB97
-24
JB97
-25
JB97
-26
JB97
-27
JB97
-28
JB97
-29
JB97
-30
JB97
-31
JB97
-32
JB97
-33
JB97
-34
JB97
-36
JB97
-39A
JB97
-39B
JB97
-39C
JB97
-40A
JB97
-40B
JB97
-41A
JB97
-41B
JB97
-41C
JB97
-42A
JB97
-42B
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
none
0.13
020
0.0
140.
270
0.66
00.
260
1.43
01.
880
5.88
091
8359
977
.93
0.14
d.s.
and
b.s.
0.60
011
22.0
680.
270
0.66
00.
260
1.43
07.
480
3.54
039
018
6470
.55
0.72
none
0.06
032
7.0
120
0.27
00.
660
0.16
011
.196
13.5
403.
020
170
168
51.4
20.
89no
ne0.
080
364.
096
0.27
00.
660
0.26
01.
430
1.88
01.
420
160
158
51.4
50.
89pa
tchy
mag
netis
m (p
o?)
0.05
316
8.0
122
0.07
00.
160
0.39
912
.340
12.9
704.
510
109
256
51.9
20.
570.
059
222.
012
20.
069
0.66
00.
207
9.53
010
.720
4.73
011
417
649
.81
0.81
0.08
621
1.0
117
0.27
00.
660
0.31
010
.400
17.2
402.
260
7729
651
.22
0.52
0.04
021
9.0
119
0.27
00.
660
0.28
010
.590
11.1
003.
530
114
286
50.6
60.
520.
044
239.
012
00.
270
0.66
00.
290
10.6
1012
.120
3.28
013
324
650
.40
0.60
barr
en -
4m so
uth
of p
its 3
&4
0.02
010
1.0
220
0.30
21.
118
0.80
15.
851
11.5
493.
689
9327
551
.54
0.48
sulp
hide
ble
bs a
nd d
.s.0.
060
365.
015
00.
270
0.66
00.
260
4.36
66.
156
4.27
217
027
652
.28
0.53
1% d
.s.0.
020
233.
014
00.
182
0.66
00.
620
27.3
0045
.041
4.81
112
029
651
.78
0.52
none
vis
ible
0.02
015
5.0
100
0.27
00.
660
0.26
01.
430
1.93
01.
689
150
238
51.3
40.
66no
ne v
isib
le0.
050
290.
011
00.
270
0.66
00.
260
1.35
62.
500
3.21
015
026
851
.63
0.61
none
vis
ible
0.07
030
9.0
110
0.27
00.
660
0.26
02.
363
3.27
12.
847
160
258
51.4
70.
63no
ne v
isib
le0.
060
293.
012
00.
270
0.66
00.
260
0.50
00.
410
3.15
015
025
751
.97
0.59
none
vis
ible
0.07
031
1.0
110
0.27
00.
660
0.26
01.
430
1.88
01.
420
160
197
52.1
50.
74no
ne v
isib
le0.
040
277.
010
09.
820
2.77
04.
520
4.02
04.
420
3.22
015
023
851
.95
0.68
none
vis
ible
0.07
030
2.0
110
0.17
80.
660
0.27
52.
323
7.31
42.
329
140
238
51.4
30.
67no
ne v
isib
le0.
060
233.
038
0.27
00.
660
0.26
01.
430
1.88
06.
444
408
1653
.95
1.40
none
vis
ible
0.07
012
1.0
950.
270
0.66
00.
260
1.43
01.
880
1.42
051
78
45.8
62.
51po
, co(
?), p
t, cp
y33
.800
5895
0.0
6360
0.27
00.
660
0.26
01.
430
125.
610
11.9
3026
1na
nana
nano
ne v
isib
le0.
090
379.
089
0.27
00.
660
0.26
01.
430
1.88
01.
840
130
267
51.7
80.
55no
ne v
isib
le0.
030
180.
098
0.27
00.
660
0.26
01.
430
1.88
01.
420
7340
749
.79
0.40
s-m
sv. p
o; m
inor
cpy
,pt(?
)15
.700
1332
0.0
1300
019
.160
39.7
5043
.170
60.7
7064
.620
35.0
9065
0na
nana
nas-
msv
. po;
min
or c
py,p
t(?)
8.54
019
6.0
6900
13.9
5032
.980
32.3
1030
.260
33.4
1031
.450
7900
nana
nana
bleb
s and
d.s.
0.00
588
.014
00.
270
0.66
00.
370
2.18
018
.070
4.91
058
nana
nana
d.s.
0.09
036
2.0
120
0.27
00.
660
0.25
01.
430
1.91
02.
440
160
296
52.0
50.
49d.
s.; p
o an
d cp
y0.
970
4892
.065
00.
170
0.66
01.
000
3.26
05.
920
21.0
3023
0026
649
.85
0.51
d.s.;
po
and
cpy
0.12
062
0.0
170
0.27
00.
660
0.26
01.
430
2.26
04.
006
520
356
50.0
00.
41cp
y=po
1.18
052
01.0
850
0.19
90.
660
0.16
04.
992
7.77
719
.907
3000
335
49.0
40.
39d.
s.0.
120
425.
015
00.
270
0.66
00.
260
1.43
03.
364
2.27
524
031
550
.70
0.42
d.s.
0.11
052
4.0
160
0.27
00.
660
0.26
01.
430
1.88
04.
650
430
365
49.1
70.
36d.
s. po
=cpy
1.86
098
92.0
1300
0.31
01.
150
0.75
07.
100
9.13
028
.210
4900
365
47.5
40.
37
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-65
JB97
-78B
JB97
-48
JB97
-49
JB98
-207
JB98
-224
JB98
-239
BJB
98-2
39C
JB98
-240
JB97
-4B
JB97
-18
JB97
-20
JB97
-24
JB97
-25
JB97
-26
JB97
-27
JB97
-28
JB97
-29
JB97
-30
JB97
-31
JB97
-32
JB97
-33
JB97
-34
JB97
-36
JB97
-39A
JB97
-39B
JB97
-39C
JB97
-40A
JB97
-40B
JB97
-41A
JB97
-41B
JB97
-41C
JB97
-42A
JB97
-42B
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
11.5
51.
080.
010.
130.
536.
910.
110.
020.
320.
130.
6299
.03
2242
536
0.08
1.58
20.9
73.
734.
8412
.93
3.06
0.02
1.11
1.63
6.82
0.74
0.10
1.34
0.60
1.12
98.8
046
33na
330.
4310
.93
0.42
0.82
3.99
14.0
612
.52
0.18
6.78
10.3
31.
990.
980.
030.
160.
060.
9210
0.10
5651
na27
01.
3841
.86
1.62
0.50
3.20
13.6
012
.96
0.21
6.13
8.59
2.52
1.06
0.03
0.21
0.08
1.88
99.3
252
52na
280
1.03
43.2
22.
320.
733.
9214
.28
10.1
90.
178.
4311
.49
2.00
0.57
0.05
na0.
050.
6210
0.29
6641
na21
01.
8918
.84
1.64
0.52
2.24
13.5
212
.39
0.20
7.90
10.2
22.
070.
250.
06na
0.06
2.97
100.
2060
46na
236
0.60
8.08
1.59
0.48
2.85
14.8
39.
860.
158.
3210
.71
1.76
1.05
0.03
na0.
091.
8310
0.28
6637
na20
22.
7946
.38
1.64
0.54
2.19
14.5
710
.55
0.18
8.31
11.1
31.
630.
590.
05na
0.04
2.23
100.
4265
42na
205
1.66
24.8
41.
440.
462.
0014
.42
10.5
30.
178.
2510
.34
1.84
0.74
0.05
na0.
042.
9810
0.32
6541
na20
81.
1728
.34
1.05
0.51
2.25
13.0
39.
740.
1710
.84
12.2
11.
380.
480.
000.
220.
020.
9510
0.82
7246
na23
01.
6619
.10
1.12
0.34
1.91
14.3
79.
910.
178.
5711
.73
1.60
0.60
0.02
0.12
0.06
0.27
100.
0567
43na
220
0.99
16.8
11.
440.
422.
0515
.29
9.30
0.16
8.48
12.4
41.
520.
390.
020.
130.
020.
3210
0.22
6838
na20
00.
7012
.97
1.22
0.36
1.88
14.9
711
.36
0.19
6.67
10.5
92.
270.
610.
040.
230.
021.
1099
.80
5847
na21
00.
7412
.95
1.41
0.41
2.76
15.8
610
.17
0.16
6.85
11.5
32.
060.
520.
030.
170.
050.
5299
.94
6140
na20
01.
4018
.21
1.30
0.37
2.30
15.7
210
.75
0.17
6.84
11.4
32.
080.
450.
040.
130.
070.
3799
.95
6042
na21
00.
9713
.84
1.19
0.36
2.28
14.5
710
.58
0.17
7.86
11.9
01.
920.
460.
030.
270.
060.
4710
0.52
6346
na22
01.
3115
.81
1.22
0.34
2.18
14.1
711
.61
0.19
7.16
11.1
72.
110.
500.
040.
150.
070.
2110
0.05
5946
na24
01.
0416
.47
1.49
0.46
2.87
15.6
411
.00
0.17
6.51
11.0
72.
150.
530.
040.
160.
040.
4210
0.16
5842
na22
01.
2617
.20
1.48
0.41
2.62
15.4
310
.28
0.17
6.75
11.0
72.
040.
670.
040.
160.
070.
9999
.54
6039
na21
02.
0224
.11
1.48
0.44
2.66
11.8
715
.48
0.21
3.42
9.87
0.08
1.24
0.09
0.05
0.06
2.02
99.6
334
46na
340
0.44
35.3
13.
140.
995.
5416
.74
14.7
90.
175.
978.
213.
361.
150.
530.
120.
070.
0599
.34
4850
na19
00.
9721
.43
1.41
0.36
16.4
8na
nana
nana
nana
na0.
1633
.80
na0.
00-
1165
9031
0.07
0.74
0.03
0.08
0.08
14.2
810
.99
0.18
7.29
10.1
41.
970.
790.
030.
410.
091.
9099
.90
6143
na22
01.
3233
.68
1.48
0.44
2.14
16.1
68.
900.
127.
339.
962.
070.
990.
021.
100.
033.
6099
.34
6635
na18
01.
1744
.61
1.13
0.40
1.53
nana
nana
nana
nana
0.14
15.7
0na
0.00
-29
0na
180
0.59
6.58
1.37
0.36
1.46
nana
nana
nana
nana
0.18
8.54
na0.
00-
180
na24
00.
474.
690.
050.
25na
nana
nana
nana
na0.
840.
00na
0.00
-35
na16
02.
5965
.58
6.18
2.70
3.40
14.2
410
.82
0.20
8.65
10.6
91.
690.
460.
030.
160.
090.
7510
0.07
6547
na19
01.
6517
.13
1.38
0.44
1.87
13.1
313
.15
0.22
8.99
10.3
71.
470.
420.
030.
240.
970.
8999
.03
6183
na21
01.
5714
.35
1.12
0.39
1.85
14.4
510
.54
0.20
8.84
9.53
1.74
0.33
0.02
0.84
0.12
3.19
99.2
566
42na
180
1.72
6.89
1.08
0.39
1.42
12.9
012
.49
0.18
9.50
10.6
31.
220.
740.
010.
201.
181.
7398
.83
6487
na19
06.
7129
.78
0.95
0.30
1.36
13.1
510
.03
0.18
9.70
11.2
01.
240.
770.
020.
210.
122.
2299
.63
6946
na19
02.
8231
.43
1.11
0.36
1.48
12.7
910
.81
0.19
9.82
11.3
21.
020.
050.
020.
240.
113.
8699
.41
6877
na17
00.
280.
820.
880.
351.
1813
.29
13.4
00.
189.
0210
.37
1.05
0.68
0.01
0.16
1.86
2.33
98.2
461
110
na18
02.
2424
.42
0.88
0.28
1.14
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-65
JB97
-78B
JB97
-48
JB97
-49
JB98
-207
JB98
-224
JB98
-239
BJB
98-2
39C
JB98
-240
JB97
-4B
JB97
-18
JB97
-20
JB97
-24
JB97
-25
JB97
-26
JB97
-27
JB97
-28
JB97
-29
JB97
-30
JB97
-31
JB97
-32
JB97
-33
JB97
-34
JB97
-36
JB97
-39A
JB97
-39B
JB97
-39C
JB97
-40A
JB97
-40B
JB97
-41A
JB97
-41B
JB97
-41C
JB97
-42A
JB97
-42B
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
1.01
2.96
8.45
1.24
14.5
06.
12na
7.66
2.16
0.34
0.08
43.
150.
664.
26 -
0.96
2.62
0.38
2.43
0.34
1.02
4.18
9.98
1.41
41.4
06.
40na
1.85
1.71
0.32
0.43
21.
630.
261.
61 -
0.35
0.94
0.14
0.88
0.13
0.31
6.76
15.5
22.
1315
8.40
9.66
na1.
902.
690.
860.
534
2.94
0.48
3.18
-0.
671.
850.
261.
760.
270.
389.
1620
.28
2.63
189.
0011
.37
na2.
233.
010.
890.
534
3.06
0.49
3.28
-0.
681.
850.
281.
740.
280.
226.
1413
.08
1.72
158.
507.
3844
.81
1.43
1.90
0.64
0.34
22.
220.
392.
4615
.43
0.56
1.62
0.25
1.65
0.24
0.26
6.62
14.5
92.
0146
7.80
9.33
55.7
91.
712.
380.
780.
486
2.86
0.46
2.96
17.2
40.
631.
780.
271.
530.
250.
186.
6313
.78
1.71
223.
407.
3043
.00
1.14
1.70
0.56
0.31
21.
850.
312.
1513
.93
0.47
1.41
0.20
1.31
0.21
0.17
5.63
11.9
31.
5415
5.30
6.36
41.3
01.
161.
580.
530.
312
1.71
0.31
2.07
13.9
80.
481.
270.
201.
290.
190.
235.
8212
.50
1.67
160.
806.
8937
.60
1.21
1.72
0.60
0.36
02.
180.
362.
5513
.04
0.54
1.48
0.24
1.47
0.23
0.13
4.44
9.73
1.27
158.
705.
71na
-1.
510.
540.
288
1.66
0.27
1.85
-0.
391.
110.
161.
040.
160.
145.
6312
.43
1.56
147.
406.
88na
-1.
740.
580.
318
1.94
0.34
2.27
-0.
521.
480.
221.
500.
220.
135.
0711
.12
1.40
134.
506.
32na
-1.
670.
540.
312
1.85
0.33
2.17
-0.
491.
420.
211.
390.
210.
186.
6814
.86
1.94
256.
208.
74na
-2.
230.
800.
396
2.34
0.38
2.45
-0.
541.
470.
221.
340.
210.
165.
7412
.71
1.63
215.
207.
33na
-1.
860.
700.
366
2.04
0.33
2.17
-0.
471.
350.
191.
260.
180.
155.
5612
.64
1.69
219.
907.
37na
-1.
920.
710.
378
2.10
0.35
2.27
-0.
471.
340.
191.
220.
180.
145.
3912
.27
1.63
202.
507.
35na
1.26
1.99
0.70
0.35
42.
060.
352.
24 -
0.49
1.38
0.19
1.26
0.19
0.19
6.82
15.3
72.
0020
4.30
8.99
na1.
602.
380.
810.
444
2.49
0.41
2.59
-0.
581.
580.
231.
470.
220.
186.
7014
.68
1.89
220.
208.
55na
1.58
2.25
0.79
0.40
82.
360.
402.
60 -
0.55
1.56
0.21
1.42
0.21
0.18
6.62
14.5
51.
8921
4.40
8.33
na1.
492.
070.
720.
402
2.32
0.37
2.50
-0.
531.
460.
211.
360.
210.
3613
.44
29.3
03.
8278
2.80
16.8
7na
2.46
4.18
1.59
0.83
94.
330.
744.
79 -
1.07
3.06
0.42
2.54
0.36
0.87
23.8
355
.42
7.40
606.
6032
.97
na4.
666.
902.
261.
505
6.00
0.90
5.67
-1.
163.
190.
462.
890.
440.
030.
647.
400.
231.
101.
11na
0.24
0.20
0.03
-0.
170.
030.
19 -
0.04
0.36
0.03
0.20
0.04
0.15
6.03
13.1
31.
6415
3.30
7.08
na1.
281.
760.
600.
330
1.97
0.33
2.31
-0.
541.
540.
221.
490.
220.
104.
509.
931.
2117
4.60
5.35
na0.
751.
340.
530.
240
1.46
0.26
1.76
-0.
401.
160.
171.
040.
160.
103.
828.
591.
0613
.30
4.57
na0.
861.
020.
27 -
1.02
0.17
1.17
-0.
260.
690.
100.
680.
100.
020.
220.
730.
144.
600.
98na
0.13
0.45
0.22
-0.
550.
100.
77 -
0.18
0.53
0.08
0.59
0.10
0.34
15.3
129
.19
3.26
210.
6012
.38
na2.
162.
280.
78 -
1.69
0.25
1.50
-0.
290.
810.
120.
770.
110.
145.
1111
.01
1.38
136.
705.
95na
1.12
1.59
0.54
0.29
41.
750.
301.
96 -
0.43
1.28
0.20
1.26
0.19
0.15
4.78
10.5
21.
3713
3.00
6.07
na1.
051.
580.
540.
306
1.75
0.32
2.17
-0.
461.
320.
191.
290.
200.
105.
7212
.30
1.53
150.
706.
52na
0.89
1.71
0.63
0.24
61.
860.
301.
95 -
0.41
1.16
0.17
1.08
0.16
0.09
3.71
8.15
1.04
107.
904.
65na
0.84
1.17
0.45
0.23
41.
420.
241.
68 -
0.38
1.06
0.16
1.04
0.16
0.10
4.30
9.43
1.18
135.
805.
02na
0.92
1.34
0.48
0.25
21.
550.
271.
76 -
0.41
1.17
0.17
1.14
0.17
0.08
3.84
8.22
1.03
266.
504.
51na
0.73
1.20
0.56
0.21
61.
420.
241.
68 -
0.37
1.04
0.17
1.04
0.15
0.08
3.57
7.97
1.01
139.
604.
46na
0.74
1.16
0.44
0.22
21.
320.
251.
59 -
0.36
1.03
0.16
1.00
0.14
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
Tow
nshi
pSt
udy
Are
aD
escr
iptio
n 1
Roc
k T
ype
Fiel
d N
ame
JB97
-54B
Wel
lsA
pple
by L
k Tr
avA
pple
by L
k; c
g ga
bbro
cou
ntry
rock
to su
lph;
~3m
eas
t of s
ulph
ide
sect
ion
gabb
roJB
97-5
5W
ells
App
leby
Lk
Trav
App
leby
Lk;
mg-
cg; n
o vi
sibl
e su
lphi
des;
sout
h si
de o
f hig
hway
gabb
roJB
97-5
6W
ells
App
leby
Lk
Trav
App
leby
Lk;
mg;
no
visi
ble
sulp
hide
s; so
uth
side
of h
ighw
ayga
bbro
JB97
-57
Wel
lsA
pple
by L
k Tr
avA
pple
by L
k; m
g; n
o vi
sibl
e su
lphi
des;
sout
h si
de o
f hig
hway
; aug
ite p
heno
crys
ts?
gabb
roJB
97-5
8W
ells
App
leby
Lk
Trav
App
leby
Lk;
mg;
no
visi
ble
sulp
hide
s; so
uth
side
of h
ighw
ayga
bbro
JB97
-62
Wel
lsB
assw
ood
Lk T
rav
fg-m
g; m
agne
tic p
atch
esga
bbro
JB97
-67
Jane
sC
hini
guch
im
g ga
bbro
; lay
erin
g pr
esen
t at 3
0Az
gabb
roJB
97-7
0BLo
uise
Lo
uie
Lake
fg to
mg
gabb
ro fr
om w
all r
ock
arou
nd su
lphi
de ri
ch "
pod"
gabb
roJB
97-7
0CLo
uise
Lo
uie
Lake
mg
opx.
(?) g
abbr
o; N
orth
con
tact
with
sulp
hide
s in
pit;
alte
red
loca
llyga
bbro
JB97
-70D
Loui
se
Loui
e La
kefg
-mg
gabb
ro; f
rom
o/c
abo
ut 8
m so
uthw
est o
f pit
gabb
roJB
97-7
4AW
ater
sM
akad
am
g; a
ltere
d ga
bbro
with
chl
orite
, bio
tite
and
actin
olite
; pit
on h
ill 1
30N
/170
Ega
bbro
JB97
-75
Wat
ers
Mak
ada
cg to
peg
mat
itic;
segg
rega
tion
pod
gabb
roJB
97-7
6AW
ater
sM
akad
am
g; w
allro
ck b
y m
sv. Q
-C v
ein
gabb
roJB
97-7
7AW
ater
sM
akad
acg
gab
bro;
from
pit
on si
de o
f hill
; fro
m fr
esh
rock
gabb
roJB
97-7
7BW
ater
sM
akad
avc
g to
peg
mat
itic
gabb
ro; f
rom
bla
sted
rubb
lega
bbro
JB97
-78A
Wat
ers
Mak
ada
fg a
nd sh
eare
d ga
bbro
with
blu
e qt
z ey
esga
bbro
JB97
-84D
Loui
seLo
uie
Lake
mg;
wal
l roc
k ad
jace
nt to
smal
l pit
with
sulp
hide
sga
bbro
JB97
-87A
Jane
sC
hini
guch
i T1
Det
ail
mg;
TR
AV
ERSE
STA
RT
- nor
th e
nd o
f tre
nch
1 cl
earin
g; h
eadi
ng 1
80ga
bbro
JB97
-87B
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- tra
vers
ega
bbro
JB97
-87C
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87D
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87E
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87F
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87G
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87H
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ru
sty
area
; tra
vers
ega
bbro
JB97
-87I
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- ed
ge o
f rus
ty a
rea;
tra
vers
ega
bbro
JB97
-87J
Jane
sC
hini
guch
i T1
Det
ail
mg;
tren
ch 1
- tra
vers
ega
bbro
JB97
-87K
Jane
sC
hini
guch
i T1
Det
ail
mg;
TR
AV
ERSE
EN
D -
trenc
h 1
gabb
roJB
97-9
3Po
rter
Big
Sw
ansh
eare
d; B
ig S
wan
-mai
n sk
arn;
mai
n A
s-sh
ear z
one
that
x-c
uts g
abbr
oga
bbro
JB97
-99
Scad
ding
Scad
ding
mg;
pro
xim
al to
sed-
gabb
ro c
onta
ct; s
imila
r to
Alw
yn; s
wam
p to
Nga
bbro
JB97
-103
EK
elly
Kuk
agam
i Det
ail
mg;
fels
ic in
wea
ther
ing/
colo
ur>p
it sa
mpl
es; a
bout
13.
0m e
ast o
f pit
area
gabb
roJB
97-1
06A
Jane
sC
hini
guch
iTr
ench
T-2
on
Falc
o m
ap; a
bout
13.
5 m
sout
h of
nor
th e
nd o
f tre
nch
gabb
roJB
97-1
06C
Jane
sC
hini
guch
iTr
ench
T-2
on
Falc
o m
ap; a
bout
26.
0 m
sout
h of
nor
th e
nd o
f tre
nch
gabb
roJB
98-1
14W
ater
sM
akad
a Tr
aver
sem
g; n
on-m
agne
tic; m
assi
ve w
ith ir
regu
lar f
ract
ures
gabb
ro
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-54B
JB97
-55
JB97
-56
JB97
-57
JB97
-58
JB97
-62
JB97
-67
JB97
-70B
JB97
-70C
JB97
-70D
JB97
-74A
JB97
-75
JB97
-76A
JB97
-77A
JB97
-77B
JB97
-78A
JB97
-84D
JB97
-87A
JB97
-87B
JB97
-87C
JB97
-87D
JB97
-87E
JB97
-87F
JB97
-87G
JB97
-87H
JB97
-87I
JB97
-87J
JB97
-87K
JB97
-93
JB97
-99
JB97
-103
EJB
97-1
06A
JB97
-106
CJB
98-1
14
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
d.s.
0.09
035
2.0
790.
270
0.66
00.
210
1.43
01.
760
6.29
017
012
1051
.07
1.13
none
0.08
035
8.0
100
0.27
00.
660
0.26
01.
430
1.88
02.
710
170
168
51.5
60.
87no
ne0.
070
375.
011
00.
589
0.66
00.
442
4.34
33.
438
3.61
316
018
851
.48
0.80
none
0.08
042
2.0
110
0.27
00.
660
0.26
05.
000
1.88
04.
210
180
168
51.6
60.
88no
ne0.
080
402.
011
00.
270
0.66
00.
260
7.84
08.
420
8.56
017
015
851
.69
0.93
d.s.;
dis
s. m
agne
tite
0.04
029
4.0
112
0.27
00.
660
1.05
011
.130
8.24
03.
790
120
229
51.9
90.
72no
ne0.
032
152.
042
- -
-17
.000
32.0
001.
000
9436
550
.20
0.40
d.s.
- po>
>cpy
/py
5.11
069
38.0
1069
1.26
01.
710
1.74
010
.670
50.1
605.
100
539
336
50.4
10.
46d.
s.; p
o>>c
py0.
100
407.
018
80.
270
0.66
00.
260
7.40
08.
150
6.37
014
131
450
.68
0.39
none
vis
ible
0.07
032
6.0
180
0.27
00.
660
0.26
06.
500
8.21
05.
170
143
315
51.5
40.
41po
>cpy
+/-
pn?
1.05
014
55.0
210
0.27
00.
660
0.26
01.
430
10.4
305.
770
278
1448
84.2
20.
39po
>cpy
- D
ean
Peke
skis
' are
a0.
030
281.
053
0.27
00.
660
0.26
01.
430
1.88
01.
420
112
417
54.4
03.
54d.
s. - p
o>cp
y0.
150
228.
017
00.
270
0.66
01.
100
9.56
013
.450
5.87
045
206
53.3
70.
73d.
s. an
d bl
ebs;
po>
cpy
0.19
032
1.0
85 -
- -
- -
-15
018
850
.82
0.83
d.s.
and
bleb
- po
>cpy
0.85
015
63.0
190
0.27
00.
660
0.67
09.
280
15.1
7028
8.75
088
012
852
.03
1.02
d.s.
0.17
030
9.0
940.
270
0.66
00.
820
5.00
010
.410
2.04
082
185
48.4
40.
78su
lphi
de b
x-st
ringe
rs a
nd b
.s.0.
040
95.0
930.
270
0.66
00.
260
5.44
06.
430
8.67
018
295
53.0
50.
46d.
s.0.
027
204.
058
- -
-12
.000
25.0
003.
000
8727
650
.77
0.52
d.s.
- int
erst
itial
0.12
164
0.0
218
- -
-53
.000
335.
000
33.0
0066
027
650
.31
0.52
d.s.
- int
erst
itial
1.78
086
02.0
3029
- -
-42
9.00
027
50.0
0026
1.00
070
3130
647
.92
0.45
d.s.
- int
erst
itial
3.18
315
941.
049
95 -
- -
549.
000
3218
.000
538.
000
9458
286
45.0
10.
46d.
s. - i
nter
stiti
al2.
169
1245
8.0
3535
- -
-50
3.00
033
64.0
0045
5.00
010
301
276
47.3
80.
49d.
s. - i
nter
stiti
al2.
341
1194
4.0
3698
- -
-42
3.00
024
38.0
0041
0.00
094
6829
646
.73
0.47
d.s.
- int
erst
itial
1.78
084
56.0
2284
- -
-28
3.00
015
41.0
0033
7.00
062
2731
648
.03
0.44
d.s.
- int
erst
itial
1.82
686
40.0
2790
- -
-28
5.00
016
23.0
0027
9.00
058
9134
647
.92
0.41
d.s.
- int
erst
itial
1.11
754
26.0
1626
- -
-16
0.00
090
5.00
016
0.00
037
6932
648
.75
0.43
d.s.
- int
erst
itial
0.71
647
00.0
1014
- -
-12
6.00
062
7.00
015
6.00
030
7230
648
.25
0.46
d.s.
0.09
756
8.0
161
- -
-17
.000
51.0
0015
.000
341
326
50.3
50.
46se
mi-m
assi
ve0.
160
348.
045
0.27
00.
660
0.26
09.
070
9.12
026
.800
7515
952
.66
1.10
d.s.
- per
vasi
ve a
nd m
agm
atic
0.05
360
0.0
760.
100
0.66
00.
260
1.43
03.
000
1.50
010
714
950
.85
0.98
none
vis
ible
0.01
4 -
125
0.20
00.
660
0.50
015
.000
15.0
001.
200
9425
650
.86
0.56
none
0.06
540
0.0
124
0.27
00.
660
1.10
021
.000
38.0
002.
200
9030
649
.97
0.48
none
0.03
940
0.0
117
0.20
00.
660
0.70
012
.000
20.0
001.
900
8625
649
.55
0.57
none
0.01
457
.031
10.
392
1.25
00.
873
5.47
06.
070
2.43
037
304
50.8
30.
35
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-54B
JB97
-55
JB97
-56
JB97
-57
JB97
-58
JB97
-62
JB97
-67
JB97
-70B
JB97
-70C
JB97
-70D
JB97
-74A
JB97
-75
JB97
-76A
JB97
-77A
JB97
-77B
JB97
-78A
JB97
-84D
JB97
-87A
JB97
-87B
JB97
-87C
JB97
-87D
JB97
-87E
JB97
-87F
JB97
-87G
JB97
-87H
JB97
-87I
JB97
-87J
JB97
-87K
JB97
-93
JB97
-99
JB97
-103
EJB
97-1
06A
JB97
-106
CJB
98-1
14
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
13.2
014
.59
0.19
5.34
8.29
2.93
1.22
0.05
0.16
0.09
1.50
99.5
146
58na
330
0.28
51.9
62.
300.
684.
4814
.06
12.4
20.
196.
529.
122.
161.
470.
030.
090.
081.
2899
.68
5545
na26
01.
0863
.25
1.90
0.55
3.58
14.1
311
.85
0.19
6.74
10.2
42.
130.
960.
010.
140.
071.
0299
.55
5748
na26
01.
2938
.00
1.60
0.47
3.14
13.7
612
.82
0.20
6.40
10.0
22.
130.
920.
030.
160.
080.
9399
.75
5450
na28
01.
2035
.75
1.75
0.53
3.53
13.9
312
.68
0.19
6.38
10.3
02.
270.
640.
030.
180.
080.
9710
0.01
5450
na29
01.
3126
.09
1.74
0.54
3.54
16.1
411
.89
0.18
6.03
9.97
2.42
0.66
0.06
0.04
0.04
0.58
100.
6454
4611
320
61.
2625
.90
2.22
0.69
3.17
14.2
48.
790.
149.
2713
.07
1.54
0.44
0.04
na0.
032.
1510
0.28
7113
7130
2.68
13.9
70.
850.
261.
3715
.22
8.53
0.13
8.68
12.7
11.
660.
440.
030.
165.
112.
0810
0.35
7029
450
018
38.
2359
.93
1.46
0.47
1.94
11.9
49.
900.
1711
.70
11.7
21.
310.
380.
030.
220.
102.
1810
0.40
7347
367
208
1.05
14.7
60.
850.
271.
2312
.56
9.21
0.16
11.2
112
.24
1.32
0.40
0.03
0.23
0.07
1.55
100.
6374
4733
321
00.
5615
.46
0.90
0.28
1.22
5.64
3.45
0.01
1.76
0.40
2.48
0.12
0.01
0.05
1.05
1.69
100.
1754
3419
431
0.11
1.76
4.24
1.76
5.06
12.7
814
.51
0.22
3.15
6.84
2.29
1.48
0.24
0.32
0.03
0.55
100.
0034
4376
236
4.51
67.8
76.
051.
8419
.66
14.8
58.
060.
108.
498.
283.
360.
780.
06na
0.15
1.64
99.7
271
6046
323
41.
2224
.10
2.08
0.75
3.04
15.2
711
.52
0.13
6.00
9.04
3.61
0.90
0.03
0.40
0.19
0.96
99.1
155
37na
230
1.06
20.5
01.
730.
693.
9612
.50
13.9
30.
166.
627.
604.
090.
480.
050.
200.
851.
6210
0.10
5384
na30
00.
4010
.44
1.66
0.75
4.44
13.9
616
.41
0.13
9.68
0.66
0.63
5.97
0.02
0.31
0.17
2.14
98.8
258
36na
360
15.7
140
0.00
4.21
1.65
2.73
13.3
09.
010.
1610
.71
11.4
11.
610.
580.
050.
050.
040.
4510
0.79
7339
500
194
1.36
21.8
01.
650.
532.
2913
.83
10.0
70.
198.
3711
.37
1.14
0.56
0.07
na0.
033.
4510
0.34
6618
8553
1.51
20.3
51.
370.
431.
9913
.94
10.4
80.
188.
3111
.53
1.28
0.71
0.06
na0.
123.
0410
0.36
6520
5747
2.49
29.5
11.
320.
431.
9213
.66
12.9
00.
158.
0210
.30
0.46
0.18
0.07
na1.
783.
9598
.06
5997
159
420.
524.
641.
170.
361.
8313
.06
13.6
10.
167.
4310
.02
1.17
0.65
0.05
na3.
185.
4597
.07
5615
064
372.
7032
.40
1.08
0.32
1.60
13.0
713
.24
0.18
8.06
9.58
0.54
0.49
0.05
na2.
174.
4697
.54
5911
474
482.
0122
.98
1.16
0.37
1.81
13.4
712
.81
0.16
7.61
10.3
60.
670.
300.
06na
2.34
4.19
96.8
358
119
114
440.
8010
.18
1.16
0.35
1.65
13.6
412
.05
0.16
8.22
10.6
90.
160.
490.
07na
1.78
4.38
98.3
361
8877
441.
7620
.25
1.08
0.32
1.60
13.8
711
.64
0.15
8.18
11.2
30.
760.
430.
06na
1.83
3.49
98.1
462
9811
235
1.21
13.1
81.
010.
311.
4013
.70
10.9
30.
168.
5411
.30
0.96
0.52
0.05
na1.
123.
8199
.15
6560
8135
1.82
21.3
41.
030.
321.
5313
.69
10.0
60.
158.
4311
.59
1.17
0.43
0.06
na0.
724.
7999
.08
6649
148
370.
9614
.61
1.00
0.32
1.52
14.5
49.
170.
168.
4312
.28
0.91
0.43
0.07
na0.
103.
4110
0.21
6821
109
370.
9214
.43
1.13
0.35
1.69
16.2
811
.93
0.09
5.71
3.41
3.45
4.06
0.11
0.10
0.16
1.20
100.
0053
948
247
12.1
920
2.08
3.47
1.21
5.70
13.8
713
.91
0.22
5.89
6.69
3.37
1.33
0.11
na0.
053.
0310
0.25
50na
na26
90.
5053
.55
2.49
0.82
3.98
14.2
710
.70
0.19
8.50
11.9
41.
650.
420.
08na
0.01
1.14
100.
3165
nana
215
1.06
14.9
01.
290.
361.
9614
.51
9.61
0.17
8.32
10.9
91.
360.
630.
06na
0.07
3.97
100.
0767
nana
199
1.96
23.3
11.
260.
391.
8814
.13
10.2
50.
187.
9410
.52
1.95
0.62
0.07
na0.
044.
4710
0.25
64na
na20
70.
9021
.05
1.32
0.41
2.62
10.5
08.
790.
1413
.46
11.5
71.
460.
290.
00na
0.01
2.58
99.9
778
52na
230
0.60
6.82
0.79
0.25
1.33
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-54B
JB97
-55
JB97
-56
JB97
-57
JB97
-58
JB97
-62
JB97
-67
JB97
-70B
JB97
-70C
JB97
-70D
JB97
-74A
JB97
-75
JB97
-76A
JB97
-77A
JB97
-77B
JB97
-78A
JB97
-84D
JB97
-87A
JB97
-87B
JB97
-87C
JB97
-87D
JB97
-87E
JB97
-87F
JB97
-87G
JB97
-87H
JB97
-87I
JB97
-87J
JB97
-87K
JB97
-93
JB97
-99
JB97
-103
EJB
97-1
06A
JB97
-106
CJB
98-1
14
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
0.30
9.83
22.2
52.
9118
9.10
13.3
0na
2.31
3.47
1.06
0.67
73.
610.
593.
84 -
0.81
2.22
0.32
2.12
0.32
0.26
7.87
17.6
12.
3122
3.50
10.1
2na
2.07
2.74
0.86
0.52
22.
720.
462.
97 -
0.65
1.77
0.25
1.66
0.25
0.36
7.12
15.7
92.
0923
2.20
9.45
na1.
822.
560.
820.
480
2.61
0.44
2.89
-0.
581.
680.
251.
500.
230.
277.
5817
.27
2.29
231.
9010
.43
na2.
022.
720.
880.
528
2.95
0.49
3.27
-0.
691.
820.
281.
780.
260.
527.
5517
.06
2.25
204.
3010
.42
na1.
982.
780.
900.
558
2.95
0.49
3.26
-0.
671.
820.
261.
760.
280.
238.
6619
.91
2.40
203.
5010
.09
na1.
932.
430.
930.
432
2.66
0.45
2.66
-0.
591.
570.
231.
550.
24 -
3.85
8.29
1.05
139.
304.
7130
.43
0.88
1.31
0.45
0.24
01.
610.
281.
8311
.41
0.39
1.16
0.17
1.08
0.17
0.21
5.16
11.2
21.
3831
.40
6.08
na1.
271.
280.
350.
276
1.45
0.26
1.66
-0.
381.
380.
161.
170.
180.
093.
657.
861.
0211
3.80
4.52
na0.
991.
130.
460.
234
1.42
0.27
1.63
-0.
391.
170.
161.
060.
150.
103.
447.
750.
9997
.10
4.37
na1.
081.
270.
400.
246
1.46
0.26
1.65
-0.
411.
150.
161.
120.
160.
755.
1210
.69
1.28
19.5
04.
95na
3.39
0.84
0.26
0.23
40.
600.
090.
38 -
0.10
0.65
0.04
0.34
0.06
1.35
26.2
658
.08
7.22
178.
4029
.63
na5.
326.
821.
832.
122
7.38
1.21
6.85
-1.
504.
060.
563.
810.
550.
255.
9013
.44
1.73
203.
107.
59na
1.72
2.16
0.72
0.43
82.
440.
442.
58 -
0.57
1.60
0.21
1.41
0.21
0.33
9.52
21.0
62.
7431
1.00
11.9
5na
1.35
3.05
1.22
0.49
82.
940.
473.
01 -
0.62
1.72
0.25
1.56
0.25
0.38
8.09
20.9
13.
0117
2.00
13.6
7na
2.20
3.60
0.96
0.61
13.
750.
654.
37 -
0.92
2.52
0.35
2.21
0.31
0.45
12.4
227
.40
3.41
40.2
013
.57
na2.
392.
530.
480.
468
1.79
0.22
1.18
-0.
190.
520.
060.
460.
080.
195.
9012
.42
1.50
105.
006.
62na
1.48
1.52
0.45
0.27
61.
600.
291.
84 -
0.42
1.18
0.16
1.13
0.17
na5.
4811
.85
1.50
140.
206.
5444
.03
1.26
1.72
0.54
0.31
21.
980.
342.
3513
.86
0.50
1.49
0.22
1.39
0.21
na5.
3611
.50
1.45
153.
306.
5242
.38
1.27
1.70
0.56
0.31
21.
990.
342.
3214
.06
0.51
1.49
0.22
1.39
0.22
na4.
8310
.44
1.34
123.
905.
8037
.84
1.15
1.51
0.49
0.27
01.
790.
322.
0912
.64
0.45
1.32
0.20
1.17
0.19
na4.
429.
651.
2512
0.00
5.45
35.4
31.
051.
480.
490.
276
1.68
0.30
2.01
11.8
90.
431.
240.
171.
180.
18na
4.87
10.1
31.
2811
2.30
5.54
39.0
81.
171.
460.
500.
294
1.75
0.31
2.10
12.3
40.
441.
340.
181.
260.
19na
4.84
10.4
61.
3512
9.50
5.75
35.7
51.
101.
500.
520.
282
1.65
0.31
2.10
12.6
40.
451.
330.
191.
200.
19na
4.53
9.84
1.25
116.
305.
3434
.80
1.05
1.46
0.48
0.26
41.
700.
301.
9411
.87
0.44
1.26
0.18
1.17
0.19
na4.
259.
291.
2012
8.40
5.07
31.5
80.
961.
380.
450.
246
1.64
0.28
1.91
11.3
90.
401.
200.
171.
150.
17na
4.42
9.52
1.22
130.
705.
2534
.76
0.99
1.32
0.48
0.25
81.
600.
281.
9911
.79
0.42
1.20
0.17
1.17
0.18
na4.
389.
591.
2415
5.10
5.23
34.0
01.
011.
370.
490.
276
1.72
0.29
1.96
12.1
90.
421.
240.
181.
110.
18na
4.81
10.4
61.
3215
4.70
5.72
37.2
51.
091.
510.
510.
276
1.75
0.30
2.09
12.6
60.
441.
290.
191.
250.
190.
4210
.87
26.0
93.
3216
2.80
13.3
1na
2.39
3.46
0.75
0.65
93.
970.
795.
05 -
1.08
2.80
0.37
2.29
0.29
na9.
7420
.82
2.64
324.
7011
.39
73.0
82.
172.
930.
960.
588
3.26
0.53
3.43
19.3
30.
692.
020.
281.
840.
28na
5.44
11.7
21.
5013
1.30
6.44
45.6
71.
281.
760.
580.
336
2.07
0.36
2.43
14.8
30.
521.
520.
221.
480.
22na
5.34
11.3
01.
4215
4.70
6.14
42.0
81.
181.
620.
530.
288
1.91
0.33
2.17
13.4
30.
461.
400.
201.
270.
21na
6.08
12.6
41.
5917
1.10
6.92
42.9
41.
211.
800.
580.
342
2.16
0.36
2.39
15.0
90.
521.
520.
221.
410.
220.
182.
435.
540.
7811
8.50
3.63
26.8
90.
831.
060.
360.
210
1.22
0.20
1.34
8.49
0.30
0.85
0.12
0.79
0.12
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
Tow
nshi
pSt
udy
Are
aD
escr
iptio
n 1
Roc
k T
ype
Fiel
d N
ame
JB98
-117
BN
airn
Nai
rn W
right
mg;
from
in tr
ench
gabb
roJB
98-1
17C
Nai
rnN
airn
Wrig
htm
g; fr
om in
tren
ch a
rea
- bla
st ro
ck; v
ery
wea
ther
ed; p
od-li
ke su
lphi
des
gabb
roJB
98-1
18W
ells
Bas
swoo
d Lk
Tra
vm
g; <
1% q
tz; b
ase
of la
rge
gabb
ro h
ill, w
est o
f HW
Y#1
29;q
tz?
gabb
roga
bbro
JB98
-148
Lorn
eB
ell L
ake
Trav
fg; s
mal
l o/c
on
N. s
ide
of o
ld ro
ad; ~
75m
at 3
15az
from
stat
. 147
-Tra
vers
ega
bbro
JB98
-149
Lorn
eB
ell L
ake
Trav
fg; s
mal
l o/c
in tr
ees;
~75
m a
t 315
az fr
om st
at. 1
48 -
Trav
erse
gabb
roJB
98-1
50Lo
rne
Bel
l Lak
e Tr
avfg
; rid
ge o
verlo
okin
g sh
allo
w v
alle
y &
pow
er li
nes;
~90
m fr
om st
at. 1
49
gabb
roJB
98-1
51C
Lorn
eB
ell L
ake
Trav
fg; T
RA
VER
SE E
ND
- no
rther
nmos
t edg
e of
ridg
e by
old
pit;
~15
m fr
om st
at. 1
50ga
bbro
JB98
-174
Cur
tinC
harlt
on L
k C
liff
fg; ~
30m
NW
of s
tat.
173;
trav
erse
gabb
roJB
98-1
75C
urtin
Cha
rlton
Lk
Clif
fm
g; ~
5m N
W o
f sta
t. 17
4; tr
aver
sega
bbro
JB98
-177
Cur
tinC
harlt
on L
k C
liff
mg;
~5m
NW
of s
tat.
176;
nea
r con
tact
w g
abbr
o; tr
aver
sega
bbro
JB98
-178
Cur
tinC
harlt
on L
k C
liff
mg;
~50
m N
W o
f sta
t. 17
7; tr
aver
sega
bbro
JB98
-179
Cur
tinC
harlt
on L
k C
liff
mg-
cg; ~
50m
NW
of s
tat.
178;
trav
erse
gabb
roJB
98-1
80C
urtin
Cha
rlton
Lk
Clif
fm
g; ~
50m
NW
of s
tat.
179;
~30
m E
of s
hore
; tra
vers
ega
bbro
JB98
-181
Cur
tinC
harlt
on L
k C
liff
mg-
cg; ~
50m
NW
of s
tat.
180;
~35
m E
of s
hore
; tra
vers
ega
bbro
JB98
-183
Cur
tinC
harlt
on L
k C
liff
mg;
~50
m N
W o
f sta
t. 18
2; ~
15m
E o
f sho
re; t
rave
rse
gabb
roJB
98-1
84C
urtin
Cha
rlton
Lk
Clif
fm
g; ~
50m
NW
of s
tat.
183;
SE
of c
abin
; tra
vers
ega
bbro
JB98
-190
ER
athb
unR
athb
unm
g; R
athb
un L
ake
Show
ing;
from
mai
n pi
t are
aga
bbro
JB98
-194
Kel
lyC
araf
el B
ay T
rav
fg-m
g; T
RA
VER
SE S
TAR
T - ~
7m u
p hi
ll fa
ce fr
om N
. sho
re o
f Car
afel
Bay
gabb
roJB
98-1
95K
elly
Car
afel
Bay
Tra
vm
g; m
t-bea
ring;
~30
m fr
om la
ke sh
ore
- Tra
vers
ega
bbro
JB98
-196
Kel
lyC
araf
el B
ay T
rav
mg;
mt-b
earin
g; ~
75m
from
lake
shor
e; g
rano
phyr
ic ro
ck in
are
a - T
rave
rse
gabb
roJB
98-1
98K
elly
Car
afel
Bay
Tra
vm
g-cg
; ~50
m N
. of l
ast s
tatio
n; fr
om o
vertu
rned
tree
; peg
. in
area
- Tr
aver
sega
bbro
JB98
-199
Kel
lyC
araf
el B
ay T
rav
mg;
~80
m N
. of l
ast;
in tr
ees -
Tra
vers
ega
bbro
JB98
-200
Kel
lyC
araf
el B
ay T
rav
mg;
~10
0m N
. of l
ast -
Tra
vers
ega
bbro
JB98
-201
Kel
lyC
araf
el B
ay T
rav
mg;
~10
0m fr
om la
st; u
p on
hill
ove
r low
are
a - t
rave
rse
gabb
roJB
98-2
02K
elly
Car
afel
Bay
Tra
vm
g; ~
100m
from
last
- tra
vers
ega
bbro
JB98
-203
Kel
lyC
araf
el B
ay T
rav
mg;
on
high
hill
ove
rlook
ing
valle
y; N
/S v
alle
y to
wes
t and
E/W
to so
uth;
trav
erse
gabb
roJB
98-2
05K
elly
Car
afel
Bay
Tra
vm
g; m
t-bea
ring;
hig
hest
poi
nt o
n hi
ll - t
rave
rse
gabb
roJB
98-2
06K
elly
Car
afel
Bay
Tra
vm
g; m
t-bea
ring;
~10
0m N
. of l
ast -
Tra
vers
ega
bbro
JB98
-209
ALo
uise
Loui
e La
kem
g; 3
+00E
Pit
b/w
8+0
0 an
d 8+
50 so
uth;
new
ly b
last
edga
bbro
JB98
-209
BLo
uise
Loui
e La
kem
g; 3
+00E
Pit
b/w
8+0
0 an
d 8+
50 so
uth;
new
ly b
last
edga
bbro
JB98
-209
CLo
uise
Loui
e La
kem
g-cg
; 3+0
0E P
it b/
w 8
+00
and
8+50
sout
h; n
ewly
bla
sted
gabb
roJB
98-2
09D
Loui
seLo
uie
Lake
mg;
3+0
0E P
it b/
w 8
+00
and
8+50
sout
h; n
ewly
bla
sted
; mas
sive
sulp
hide
gabb
roJB
98-2
10A
Loui
seLo
uie
Lake
fg; f
rom
con
tact
are
a w
ith fr
ags o
f sed
in fg
-mg
gabb
roga
bbro
JB98
-212
BLo
uise
Loui
e La
kem
g; la
rge
mai
n pi
t vis
ited
last
yea
r - 1
997
gabb
ro
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-117
BJB
98-1
17C
JB98
-118
JB98
-148
JB98
-149
JB98
-150
JB98
-151
CJB
98-1
74JB
98-1
75JB
98-1
77JB
98-1
78JB
98-1
79JB
98-1
80JB
98-1
81JB
98-1
83JB
98-1
84JB
98-1
90E
JB98
-194
JB98
-195
JB98
-196
JB98
-198
JB98
-199
JB98
-200
JB98
-201
JB98
-202
JB98
-203
JB98
-205
JB98
-206
JB98
-209
AJB
98-2
09B
JB98
-209
CJB
98-2
09D
JB98
-210
AJB
98-2
12B
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
diss
and
ble
b; c
py>p
o>pn
1.30
031
45.0
1202
0.54
51.
190
1.43
032
.000
41.2
0011
.560
695
364
53.4
00.
25po
>cpy
>pn;
mas
sive
7.63
031
.037
663.
020
6.55
06.
090
218.
100
122.
600
84.6
0012
2926
547
.27
0.32
none
0.03
318
7.0
104
0.27
00.
241
1.07
98.
160
23.3
604.
310
140
188
51.4
40.
82no
ne0.
008
32.0
376
1.12
42.
380
2.50
012
.770
4.30
01.
060
3321
352
.19
0.27
none
0.00
544
.033
21.
301
2.50
01.
900
12.1
406.
480
0.76
316
253
51.0
40.
27no
ne0.
005
44.0
293
1.14
62.
540
1.54
013
.260
6.12
00.
645
3021
351
.29
0.40
none
0.00
519
.026
40.
841
1.94
01.
410
11.6
907.
090
1.43
039
214
51.3
30.
44d.
s.; n
ear c
onta
ct w
ith se
ds0.
285
1036
.013
90.
270
0.66
00.
320
8.79
010
.560
13.2
0041
226
750
.66
0.55
<<1%
d.s.
a/w
qtz
vei
ning
0.03
419
1.0
120
0.27
00.
160
0.20
28.
600
7.11
03.
040
104
376
50.1
10.
42d.
s.0.
017
105.
083
0.27
00.
190
0.26
01.
320
1.19
01.
890
154
237
52.6
60.
61no
ne0.
031
155.
011
80.
270
0.15
00.
260
1.57
01.
830
2.56
086
266
50.6
30.
53no
ne0.
070
366.
014
80.
270
0.37
00.
092
1.67
71.
750
2.23
022
125
551
.06
0.50
none
0.07
623
4.0
131
0.27
00.
660
0.26
01.
780
1.47
01.
940
161
305
51.1
90.
44no
ne0.
078
364.
098
0.27
00.
320
0.48
00.
238
0.28
21.
630
143
317
51.0
50.
48d.
s.; ru
sty
patc
hes
0.23
217
33.0
511
0.26
70.
640
1.82
058
.000
156.
000
33.5
0087
031
549
.96
0.41
none
0.03
524
1.0
175
0.07
00.
500
0.66
313
.980
55.5
004.
510
120
325
50.2
70.
44d.
s. an
d bl
eb; c
py >
> po
10.5
0088
425.
093
670.
326
7.80
0C
u-In
t39
61.0
0062
30.0
0094
1.00
037
7129
188
35.0
60.
69no
n-m
agne
tic0.
054
292.
011
70.
053
0.35
00.
434
8.35
09.
510
3.65
011
825
651
.66
0.58
10%
mag
netit
e0.
056
267.
011
60.
270
0.66
00.
277
10.6
1011
.020
2.88
010
425
751
.53
0.57
20-3
0% m
agne
tite
0.03
218
1.0
134
0.27
00.
660
0.30
914
.450
13.1
801.
420
111
356
51.1
90.
43pa
tchy
mag
netis
m (p
o?)
0.08
539
4.0
155
0.27
00.
130
0.26
01.
310
1.33
02.
500
227
246
51.4
70.
54m
ay b
e po
/ no
t mt a
s fin
e ds
0.01
320
4.0
119
0.27
00.
660
0.26
01.
290
0.97
02.
720
138
266
52.0
00.
52pa
tchy
mag
netis
m (p
o?)
0.03
726
1.0
150
0.27
00.
660
0.09
82.
570
2.23
03.
700
168
305
51.1
80.
4310
% m
t; no
v.s.
; dis
s. po
?0.
035
212.
015
30.
270
0.13
00.
096
4.10
03.
200
5.30
015
031
551
.76
0.45
10%
mt;
may
be
diss
. po?
0.07
831
1.0
148
0.27
00.
660
0.14
27.
730
7.56
05.
740
144
246
52.3
50.
57pa
tchy
mag
netis
m (p
o?)
0.05
514
7.0
150
0.05
00.
660
0.38
78.
000
9.41
02.
470
8231
551
.16
0.46
d.s.
0.01
686
.018
20.
127
0.19
00.
750
9.78
024
.600
2.63
087
395
51.0
70.
36pa
tchy
mag
netis
m (p
o?)
0.03
915
5.0
146
0.06
50.
150
0.44
610
.700
10.1
003.
280
8832
551
.92
0.45
d.s./
b.s.
- at c
onta
ct w
wal
l rck
7.39
013
560.
095
70.
512
0.83
02.
930
30.6
007.
910
7.10
014
6343
553
.69
0.15
in m
ain
area
of s
ulph
ide
pod
28.9
003.
531
781.
940
3.61
05.
860
156.
500
173.
700
38.8
0089
141
1020
.42
0.07
wal
l roc
k "a
bove
" su
lph
pod
0.03
315
4.0
990.
208
0.38
01.
170
33.2
0029
.800
2.88
034
416
63.9
00.
20m
assi
ve fr
om p
it29
.700
3.5
3332
1.68
02.
990
4.06
062
.400
278.
000
8.34
070
163
1018
.78
0.04
0.11
431
9.0
122
0.05
50.
140
0.38
410
.830
11.7
805.
580
138
256
51.3
40.
59m
ainl
y po
; cpy
in g
ab0.
125
319.
018
50.
063
0.66
00.
279
10.1
0012
.310
6.89
031
248
449
.82
0.29
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-117
BJB
98-1
17C
JB98
-118
JB98
-148
JB98
-149
JB98
-150
JB98
-151
CJB
98-1
74JB
98-1
75JB
98-1
77JB
98-1
78JB
98-1
79JB
98-1
80JB
98-1
81JB
98-1
83JB
98-1
84JB
98-1
90E
JB98
-194
JB98
-195
JB98
-196
JB98
-198
JB98
-199
JB98
-200
JB98
-201
JB98
-202
JB98
-203
JB98
-205
JB98
-206
JB98
-209
AJB
98-2
09B
JB98
-209
CJB
98-2
09D
JB98
-210
AJB
98-2
12B
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
8.92
13.2
10.
1212
.77
3.16
0.52
0.04
0.04
na1.
307.
4499
.87
6912
9na
337
0.37
2.58
5.32
2.30
3.95
8.18
24.3
10.
089.
931.
630.
490.
580.
04na
7.63
5.32
98.1
549
425
na41
51.
4127
.12
6.03
1.94
4.51
14.9
311
.30
0.18
6.28
8.17
2.98
1.17
0.09
na0.
032.
9310
0.29
5648
na20
01.
5454
.19
2.88
0.85
4.02
5.67
10.2
40.
2018
.69
10.7
11.
130.
140.
02na
0.00
80.
9410
0.20
8166
na27
40.
866.
240.
540.
170.
876.
689.
800.
1917
.41
9.53
1.51
0.13
0.02
na0.
005
3.80
100.
3881
60na
229
0.42
3.97
0.84
0.22
1.12
8.21
10.3
20.
1815
.63
9.15
1.12
0.36
0.02
na0.
005
3.68
100.
3678
58na
222
1.88
19.2
41.
040.
341.
669.
1910
.09
0.19
14.3
99.
271.
760.
430.
03na
0.00
53.
2410
0.36
77na
nana
4.62
27.1
11.
160.
331.
8614
.30
9.98
0.15
7.36
10.6
63.
500.
200.
05na
0.29
2.90
100.
3163
50na
210
0.10
5.66
1.69
0.54
2.17
15.4
08.
770.
148.
4010
.71
1.73
1.11
0.03
na0.
033.
4710
0.29
6935
na18
80.
4144
.09
1.05
0.30
1.46
14.2
610
.03
0.18
7.09
7.70
3.09
0.85
0.04
na0.
023.
6510
0.16
6236
na22
80.
2529
.51
2.66
0.84
3.00
13.8
111
.23
0.19
9.08
9.06
2.06
0.69
0.02
na0.
033.
1010
0.40
6554
na21
60.
2421
.42
1.99
0.58
2.22
12.7
39.
760.
189.
999.
841.
391.
010.
01na
0.07
3.86
100.
3370
46na
221
1.74
52.2
21.
620.
542.
1213
.16
9.51
0.16
9.91
10.1
61.
750.
810.
02na
0.08
3.14
100.
2571
39na
206
1.12
38.3
01.
370.
451.
6314
.68
9.17
0.15
7.60
10.0
62.
060.
860.
03na
0.08
4.18
100.
3266
40na
208
0.81
39.9
01.
690.
562.
0312
.81
9.18
0.15
10.9
910
.98
1.78
0.76
0.01
na0.
233.
0910
0.12
7450
na20
01.
2524
.11
1.13
0.36
1.42
14.0
57.
990.
149.
6911
.88
2.16
0.78
0.03
na0.
042.
8310
0.26
7437
na19
61.
2029
.52
1.02
0.32
1.57
12.4
621
.19
0.07
4.23
0.86
0.02
0.91
0.03
na10
.50
24.4
799
.99
3217
0na
208
2.16
36.0
42.
711.
052.
7714
.63
10.0
60.
178.
1811
.30
1.96
0.58
0.04
na0.
050.
8299
.98
6545
na23
11.
3621
.88
1.70
0.54
2.33
14.4
710
.45
0.18
7.82
11.1
51.
970.
520.
03na
0.06
1.21
99.8
964
44na
236
1.40
22.2
31.
770.
552.
4815
.26
8.89
0.16
8.84
11.8
61.
980.
500.
03na
0.03
1.12
100.
2670
43na
204
1.45
16.1
01.
130.
351.
7012
.84
10.5
50.
189.
2911
.17
1.75
0.61
0.03
na0.
091.
6810
0.11
6750
na24
91.
9523
.24
1.42
0.46
2.08
13.7
410
.28
0.17
8.73
10.9
81.
920.
510.
05na
0.01
0.79
99.6
966
46na
230
0.90
16.7
61.
600.
492.
1013
.01
10.0
20.
1610
.17
11.7
51.
960.
420.
02na
0.04
1.09
100.
2170
47na
217
1.58
14.7
21.
120.
331.
6013
.83
9.09
0.17
10.0
411
.78
1.63
0.50
0.03
na0.
040.
7910
0.07
7244
na21
70.
9213
.67
1.20
0.37
1.55
13.6
59.
690.
178.
8211
.03
1.74
0.69
0.05
na0.
081.
5110
0.27
6844
na23
51.
5022
.62
1.54
0.48
2.24
14.1
08.
760.
179.
8911
.66
1.68
0.64
0.05
na0.
061.
7310
0.30
7240
na20
11.
9824
.50
1.20
0.40
1.65
14.2
08.
110.
1610
.45
13.5
31.
440.
310.
02na
0.02
0.64
100.
2975
40na
198
0.48
9.61
0.80
0.26
1.29
14.3
48.
770.
159.
5111
.74
1.77
0.55
0.03
na0.
040.
7299
.95
7241
na20
30.
9515
.06
1.27
0.38
1.81
6.45
17.3
40.
0810
.51
3.41
0.87
0.11
0.00
na7.
396.
4699
.07
5924
5na
720.
406.
384.
171.
663.
052.
8959
.19
0.02
2.04
0.66
0.01
0.19
0.00
na28
.90
14.7
510
0.24
776
3na
430.
178.
612.
371.
191.
618.
255.
580.
0911
.34
4.98
1.87
0.06
0.03
na0.
033.
7610
0.06
8315
na86
0.52
0.71
1.34
2.88
2.52
60.4
10.
011.
900.
480.
010.
140.
03na
29.7
015
.56
99.8
87
829
na45
0.19
7.26
2.05
0.93
1.35
14.5
09.
110.
148.
3310
.30
2.01
0.98
0.04
na0.
113.
0510
0.39
6836
na21
11.
0241
.90
1.58
0.44
2.22
13.9
58.
090.
1511
.62
11.9
31.
590.
290.
02na
0.13
2.59
100.
3477
28na
163
0.52
11.5
50.
850.
231.
18
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-117
BJB
98-1
17C
JB98
-118
JB98
-148
JB98
-149
JB98
-150
JB98
-151
CJB
98-1
74JB
98-1
75JB
98-1
77JB
98-1
78JB
98-1
79JB
98-1
80JB
98-1
81JB
98-1
83JB
98-1
84JB
98-1
90E
JB98
-194
JB98
-195
JB98
-196
JB98
-198
JB98
-199
JB98
-200
JB98
-201
JB98
-202
JB98
-203
JB98
-205
JB98
-206
JB98
-209
AJB
98-2
09B
JB98
-209
CJB
98-2
09D
JB98
-210
AJB
98-2
12B
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
0.46
16.5
332
.08
3.71
6.90
13.9
277
.96
2.61
2.57
0.64
0.15
02.
420.
382.
7816
.75
0.54
1.74
0.25
1.84
0.30
0.43
15.2
030
.29
3.72
17.9
013
.78
77.7
12.
542.
720.
250.
192
2.20
0.34
2.31
13.7
90.
451.
450.
201.
400.
220.
3910
.94
22.5
42.
9323
5.50
12.3
666
.32
2.15
2.96
0.99
0.49
23.
020.
493.
1417
.96
0.67
1.91
0.24
1.67
0.26
0.13
2.39
5.10
0.71
60.5
03.
0919
.72
0.64
0.91
0.28
0.16
21.
020.
181.
307.
400.
260.
750.
100.
650.
110.
143.
127.
151.
0058
.50
4.35
19.4
20.
671.
150.
380.
162
1.22
0.20
1.32
7.90
0.28
0.78
0.11
0.70
0.11
0.19
5.21
10.2
91.
3196
.80
5.60
31.1
61.
011.
260.
460.
240
1.44
0.24
1.65
9.88
0.35
0.98
0.14
0.92
0.14
0.20
4.12
8.91
1.20
135.
205.
3734
.07
1.06
1.43
0.45
0.26
41.
590.
261.
7410
.93
0.38
1.04
0.15
0.99
0.15
0.23
6.66
13.6
61.
8120
9.30
7.48
45.1
91.
391.
960.
750.
330
2.28
0.38
2.59
16.0
90.
581.
640.
231.
470.
240.
184.
249.
151.
2119
1.50
5.46
31.8
60.
941.
390.
510.
252
1.55
0.27
1.94
12.7
00.
481.
270.
181.
240.
200.
2910
.37
20.9
62.
6815
9.10
10.9
762
.05
1.92
2.66
0.81
0.36
62.
730.
443.
2519
.74
0.67
1.92
0.27
1.74
0.28
0.24
7.10
14.4
01.
8613
5.10
7.92
42.5
41.
451.
940.
600.
318
1.99
0.36
2.30
14.0
20.
481.
400.
201.
350.
220.
226.
4413
.35
1.65
154.
107.
0640
.52
1.30
1.78
0.54
0.30
01.
900.
332.
2214
.04
0.49
1.39
0.20
1.36
0.21
0.18
5.33
10.6
61.
4113
4.80
6.03
33.8
11.
121.
630.
580.
264
1.79
0.31
2.03
12.3
10.
441.
250.
181.
320.
210.
226.
3212
.83
1.65
171.
706.
8640
.48
1.34
1.75
0.58
0.28
82.
040.
362.
3614
.02
0.48
1.43
0.21
1.48
0.21
0.16
4.38
9.13
1.17
148.
105.
1529
.17
0.99
1.38
0.46
0.24
61.
600.
271.
8011
.42
0.39
1.20
0.18
1.16
0.17
0.17
4.46
9.31
1.27
155.
805.
3234
.54
1.13
1.41
0.47
0.26
41.
750.
292.
0112
.50
0.43
1.22
0.18
1.25
0.18
0.29
7.15
13.5
31.
5275
.40
5.42
34.6
11.
190.
980.
510.
414
0.75
0.13
0.85
5.07
0.17
0.53
0.08
0.60
0.09
0.24
6.82
13.9
41.
8213
6.70
7.84
45.3
01.
522.
010.
650.
348
2.32
0.40
2.71
15.9
20.
561.
640.
231.
580.
260.
266.
7614
.05
1.82
153.
207.
9748
.34
1.50
2.16
0.66
0.34
22.
350.
402.
7216
.31
0.58
1.72
0.25
1.67
0.25
0.18
4.64
9.78
1.32
156.
605.
5933
.88
1.12
1.46
0.50
0.25
81.
650.
292.
0112
.38
0.41
1.34
0.18
1.13
0.19
0.22
5.86
12.3
31.
6215
3.60
7.09
40.2
61.
441.
800.
620.
324
2.15
0.38
2.49
15.4
90.
541.
600.
231.
700.
250.
216.
4213
.14
1.71
148.
307.
2144
.31
1.44
1.87
0.60
0.31
22.
270.
392.
5315
.37
0.53
1.59
0.24
1.54
0.24
0.16
4.54
9.40
1.27
123.
405.
3932
.88
1.10
1.48
0.50
0.25
81.
770.
301.
9612
.08
0.43
1.24
0.19
1.23
0.21
0.18
4.63
9.82
1.29
135.
505.
6835
.54
1.15
1.55
0.50
0.27
01.
720.
302.
0312
.52
0.44
1.30
0.18
1.32
0.18
0.22
6.20
13.0
91.
7315
0.50
7.49
45.2
61.
581.
980.
560.
342
2.13
0.36
2.52
15.7
90.
531.
580.
241.
490.
240.
185.
0110
.34
1.41
135.
305.
7735
.03
1.14
1.48
0.49
0.27
61.
760.
292.
1412
.79
0.44
1.29
0.19
1.21
0.20
0.15
3.84
7.94
1.08
119.
904.
7028
.06
0.93
1.24
0.41
0.21
61.
530.
271.
8110
.92
0.38
1.09
0.16
1.10
0.17
0.19
5.20
10.8
61.
4116
3.20
6.28
37.7
41.
181.
680.
580.
270
1.87
0.30
2.18
13.4
20.
491.
380.
201.
240.
200.
367.
5416
.12
1.92
19.9
07.
5876
.31
2.46
1.36
0.29
0.09
01.
250.
181.
327.
720.
250.
850.
140.
870.
130.
244.
169.
141.
1211
.30
4.34
28.4
40.
960.
800.
170.
042
0.68
0.10
0.72
3.59
0.11
0.38
0.06
0.36
0.05
0.40
10.6
524
.99
3.13
28.8
012
.32
95.6
63.
092.
250.
300.
120
1.68
0.24
1.59
3.73
0.30
0.95
0.12
0.72
0.11
0.19
3.58
8.04
0.96
8.70
3.69
41.6
11.
140.
610.
140.
024
0.50
0.07
0.50
3.19
0.10
0.32
0.05
0.30
0.05
0.21
6.01
12.5
81.
6515
4.90
6.99
46.5
31.
451.
710.
520.
354
2.10
0.37
2.42
14.1
30.
521.
450.
201.
390.
200.
144.
057.
841.
0011
5.90
4.08
24.0
70.
780.
960.
380.
174
1.12
0.20
1.41
8.28
0.30
0.93
0.14
0.90
0.12
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
Tow
nshi
pSt
udy
Are
aD
escr
iptio
n 1
Roc
k T
ype
Fiel
d N
ame
JB98
-225
AC
urtin
Cas
son
mg;
"m
alac
hite
pit"
; ne
ar L
2+00
Wga
bbro
JB98
-228
Cur
tinC
asso
n A
N3
Trav
mg;
TR
AV
ERSE
STA
RT
- Eas
t of A
N-3
; hea
din
180;
~10
m n
orth
of t
rail
gabb
roJB
98-2
29C
urtin
Cas
son
AN
3 Tr
avm
g; ~
50m
sout
h of
228
- Tr
aver
sega
bbro
JB98
-230
Cur
tinC
asso
n A
N3
Trav
mg;
~50
m so
uth
of 2
29 -
Trav
erse
gabb
roJB
98-2
31C
urtin
Cas
son
AN
3 Tr
avm
g; ~
75m
sout
h of
230
- Tr
aver
se; e
dge
of h
illga
bbro
JB98
-239
DK
elly
Kuk
agam
i Clif
ffg
-mg;
~9.
5m u
p si
de o
f hill
on
"pat
h" -
wes
t end
; tra
vers
ega
bbro
JB98
-239
EK
elly
Kuk
agam
i Clif
fm
g; ~
13.5
m u
p si
de o
f hill
on
"pat
h" -
wes
t end
; tra
vers
ega
bbro
JB98
-239
FK
elly
Kuk
agam
i Clif
fm
g; T
RA
VER
SE E
ND
; ~16
.25m
up
hill
on "
path
" - w
est e
nd; v
t gab
bro
area
gabb
roR
K-1
Wat
ers
Mak
ada
Trav
erse
mg-
vcg;
grid
115
N/1
20E;
from
pit#
2; m
iner
aliz
edga
bbro
RK
-2W
ater
sM
akad
a Tr
aver
sem
g-vc
g; g
rid 1
15N
/120
E; fr
om p
it#2;
min
eral
ized
gabb
roR
K-3
Wat
ers
Mak
ada
Trav
erse
mg-
vcg;
grid
115
N/1
20E;
from
pit#
2; m
iner
aliz
edga
bbro
RK
-4W
ater
sM
akad
a Tr
aver
sem
g-vc
g; g
rid 1
15N
/120
E; fr
om p
it#2;
min
eral
ized
gabb
roR
K-5
Wat
ers
Mak
ada
Trav
erse
mg;
grid
40N
/85E
gabb
roR
K-7
Wat
ers
Mak
ada
Trav
erse
fg-m
g; g
rid 1
30N
/55E
gabb
roR
K-8
Wat
ers
Mak
ada
Trav
erse
mg;
grid
180
N/3
5Ega
bbro
RK
-9W
ater
sM
akad
a Tr
aver
sem
g; g
rid 2
40N
/15E
gabb
roR
K-1
0W
ater
sM
akad
a Tr
aver
sem
g-cg
; grid
260
N/2
0Wga
bbro
RK
-11
Wat
ers
Mak
ada
Trav
erse
mg;
grid
70N
/60W
gabb
roR
K-1
2W
ater
sM
akad
a Tr
aver
sem
g; g
rid 4
0N/8
0Wga
bbro
RK
-13
Wat
ers
Mak
ada
Trav
erse
mg-
cg; g
rid 2
40S/
110W
gabb
roR
K-1
4W
ater
sM
akad
a Tr
aver
sem
g; g
rid 3
40S/
110W
gabb
roR
K-1
5W
ater
sM
akad
a Tr
aver
sem
g; n
orth
east
of p
rope
rty g
ridga
bbro
RK
-16
Wat
ers
Mak
ada
Trav
erse
mg;
nor
thea
st o
f pro
perty
grid
gabb
roR
K-1
7W
ater
sM
akad
a Tr
aver
sem
g; n
orth
east
of p
rope
rty g
ridga
bbro
RK
-18
Wat
ers
Mak
ada
Trav
erse
cg-v
cg; g
rid 6
0S/6
0Ega
bbro
RK
-19
Wat
ers
Mak
ada
Trav
erse
cg-p
eg; g
rid 1
50S/
110E
gabb
roJB
97-5
0W
ells
App
leby
Lk
Trav
App
leby
Lk;
mg-
vcg
gabb
ro w
pin
k st
aine
d fs
par
gran
oph
gabb
roJB
97-5
4AW
ells
App
leby
Lk
Trav
App
leby
Lk;
Q-C
vei
ns in
alte
red
and
pink
stai
ned
gabb
ro(?
); ~2
' wid
e se
ctio
ngr
anop
h ga
bbro
JB97
-63
Wel
lsB
assw
ood
Lk T
rav
mg
gabb
ro w
pin
k fs
par s
tain
ing
gran
oph
gabb
roJB
98-1
22B
ridgl
and
Bas
swoo
d Lk
Tra
vm
g-cg
; S. o
f #12
9; ra
diat
ing
amph
ib. l
aths
; pin
k fs
par;
gran
ophy
ric g
abbr
ogr
anop
h ga
bbro
JB97
-14
Kel
lyW
asha
gam
i Lak
em
g; so
uth
edge
of h
igh
o/c
hill
opx
gabb
roJB
97-1
5K
elly
Was
haga
mi L
ake
mg;
sout
h ed
ge o
f nex
t hig
h o/
c hi
llop
x ga
bbro
JB97
-16
Kel
lyW
asha
gam
i Lak
em
g; so
uth
edge
of s
mal
l kno
b so
uth
of p
eak
but o
n cl
aim
line
opx
gabb
roJB
97-4
3AJa
nes
Chi
nigu
chi
mg;
po
slig
htly
> th
an c
py b
ut c
lose
to 1
:1 ra
tio; F
alco
-tren
ches
opx
gabb
ro
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-225
AJB
98-2
28JB
98-2
29JB
98-2
30JB
98-2
31JB
98-2
39D
JB98
-239
EJB
98-2
39F
RK
-1R
K-2
RK
-3R
K-4
RK
-5R
K-7
RK
-8R
K-9
RK
-10
RK
-11
RK
-12
RK
-13
RK
-14
RK
-15
RK
-16
RK
-17
RK
-18
RK
-19
JB97
-50
JB97
-54A
JB97
-63
JB98
-122
JB97
-14
JB97
-15
JB97
-16
JB97
-43A
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
2.45
066
81.0
1447
1.02
01.
560
5.51
026
4.00
038
4.00
016
6.00
028
6334
448
.01
0.35
0.00
911
3.0
166
0.14
70.
280
0.91
021
.500
46.5
005.
500
6938
549
.51
0.37
0.01
515
3.0
172
0.11
60.
260
0.86
017
.180
63.8
004.
570
9038
449
.47
0.35
0.04
531
8.0
198
0.11
40.
250
0.57
033
.400
42.3
0015
.300
176
405
49.5
00.
350.
044
314.
015
50.
045
0.66
00.
224
9.67
09.
440
4.79
010
830
551
.16
0.40
0.08
722
1.0
120
- -
- -
- -
9528
651
.07
0.53
0.05
323
7.0
132
- -
- -
- -
112
286
50.5
40.
530.
024
180.
094
- -
- -
- -
7330
750
.93
0.52
0.71
281
0.0
500
0.29
00.
910
0.88
07.
240
9.60
08.
170
181
214
56.6
70.
330.
011
35.0
214
0.22
01.
050
1.48
06.
240
4.18
02.
090
1444
551
.30
0.28
1.41
012
92.0
679
0.46
01.
330
1.30
010
.700
12.5
9016
.700
349
194
55.5
10.
3536
.300
41.0
1049
00.
270
0.66
00.
260
1.43
01.
490
1.72
064
55
10.
450.
160.
038
219.
067
0.27
00.
660
0.26
00.
200
1.88
03.
480
136
1214
53.7
41.
190.
013
74.0
248
0.55
01.
410
1.23
07.
350
6.36
01.
820
7125
451
.08
0.43
0.01
887
.025
90.
570
1.45
01.
120
7.63
06.
590
1.49
073
234
51.9
10.
470.
014
65.0
338
1.05
02.
590
1.59
09.
270
5.38
01.
300
4615
352
.45
0.41
0.01
261
.033
51.
100
2.63
01.
850
11.0
605.
640
1.21
046
153
52.3
80.
410.
023
73.0
346
1.09
02.
580
1.84
09.
960
5.53
01.
370
5016
352
.78
0.38
0.01
464
.032
71.
040
2.46
01.
540
9.19
05.
300
1.37
045
153
52.7
90.
420.
021
84.0
137
0.06
00.
350
0.51
06.
220
7.80
01.
230
6134
751
.05
0.49
0.01
978
.013
80.
050
0.42
00.
520
6.30
08.
930
1.67
066
337
50.8
20.
500.
014
80.0
117
0.27
00.
310
0.44
04.
400
5.27
01.
100
6336
850
.75
0.50
0.01
142
.020
70.
140
0.91
00.
800
4.36
05.
940
1.42
038
475
50.5
60.
300.
021
88.0
176
0.15
00.
670
0.49
03.
120
4.44
01.
510
7326
550
.95
0.52
0.01
158
.034
21.
340
2.71
01.
800
11.3
705.
820
1.20
050
153
52.4
40.
390.
014
85.0
117
0.27
00.
330
0.41
04.
640
5.86
01.
030
6039
850
.74
0.48
none
0.11
034
7.0
650.
270
0.66
00.
260
1.43
02.
060
67.7
6017
09
1151
.72
1.37
d.s.
w v
eins
and
blo
bs o
f py
0.93
040
2.0
350.
270
0.66
00.
260
0.16
01.
880
76.1
0084
2325
51.4
90.
48no
ne0.
080
511.
082
0.27
00.
660
0.15
011
.020
1.83
014
.500
264
1311
52.4
11.
09no
ne v
isib
le0.
047
253.
041
0.27
00.
310
0.14
39.
940
2.46
03.
010
155
818
54.9
51.
54d.
s.0.
050
258.
016
00.
230
0.66
01.
120
32.5
1011
9.00
08.
010
130
336
50.4
10.
46d.
s.0.
040
358.
013
00.
270
0.66
00.
260
1.48
82.
671
2.25
716
025
651
.98
0.56
sulp
hide
ble
bs a
nd d
.s.0.
080
500.
018
00.
240
0.66
01.
061
28.1
6810
9.65
68.
586
220
276
51.7
20.
54d.
s. po
=cpy
3.50
021
450.
054
002.
943
4.99
80.
260
798.
710
7223
.970
462.
714
1300
029
645
.86
0.45
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-225
AJB
98-2
28JB
98-2
29JB
98-2
30JB
98-2
31JB
98-2
39D
JB98
-239
EJB
98-2
39F
RK
-1R
K-2
RK
-3R
K-4
RK
-5R
K-7
RK
-8R
K-9
RK
-10
RK
-11
RK
-12
RK
-13
RK
-14
RK
-15
RK
-16
RK
-17
RK
-18
RK
-19
JB97
-50
JB97
-54A
JB97
-63
JB98
-122
JB97
-14
JB97
-15
JB97
-16
JB97
-43A
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
11.9
211
.86
0.16
11.6
710
.43
1.60
0.63
0.02
na2.
453.
7210
0.37
7083
na19
40.
2122
.56
0.88
0.28
1.23
14.1
07.
610.
1510
.46
13.2
71.
480.
580.
01na
0.01
2.76
100.
3076
33na
181
0.40
20.1
50.
540.
231.
0813
.40
8.38
0.16
11.0
412
.55
1.33
0.39
0.03
na0.
023.
2410
0.34
7533
na18
60.
1812
.76
0.74
0.22
1.08
13.9
18.
140.
1610
.84
12.7
71.
420.
390.
01na
0.05
2.91
100.
4076
38na
180
0.44
11.6
10.
760.
221.
1612
.17
9.77
0.17
10.9
211
.40
1.17
0.58
0.02
na0.
042.
5810
0.34
7241
na19
90.
3517
.47
0.54
0.58
1.71
14.8
39.
390.
168.
4010
.58
2.26
0.74
0.05
na0.
092.
3010
0.31
6836
na20
33.
0529
.12
1.66
0.59
2.28
14.9
89.
300.
168.
5411
.55
1.70
0.65
0.04
na0.
052.
4010
0.39
6838
na20
81.
7826
.70
1.35
0.41
1.92
15.3
79.
970.
157.
6511
.01
1.78
0.36
0.03
na0.
022.
5410
0.31
6438
na21
11.
0611
.06
1.60
0.47
2.06
6.77
10.4
10.
1514
.56
4.11
0.36
1.05
0.03
0.06
0.71
5.36
99.8
076
70na
152
2.60
41.4
43.
181.
571.
4612
.39
8.71
0.14
11.1
79.
302.
710.
940.
030.
180.
013.
0810
0.05
7546
na20
60.
8534
.22
0.71
0.30
0.88
6.79
11.2
20.
1614
.46
4.52
0.70
0.83
0.02
0.03
1.41
5.25
99.8
175
97na
146
1.51
33.3
42.
791.
441.
960.
7676
.50
0.03
0.39
0.04
0.12
0.01
0.01
na36
.30
23.4
410
1.91
111
45na
380.
050.
043.
041.
4614
.83
11.2
50.
163.
828.
563.
350.
970.
160.
080.
041.
8899
.91
4436
na22
02.
0735
.19
4.57
1.34
7.10
10.8
49.
430.
1812
.55
11.5
51.
560.
540.
040.
130.
011.
6299
.82
7647
na22
30.
9314
.74
0.93
0.31
1.60
10.6
09.
560.
1812
.99
11.2
81.
640.
500.
040.
070.
020.
9810
0.15
7648
na23
20.
7816
.17
1.01
0.32
1.70
6.09
10.3
20.
1916
.35
11.9
91.
410.
210.
020.
060.
010.
6010
0.04
7958
na28
70.
457.
960.
780.
261.
275.
9810
.36
0.21
16.3
811
.80
1.16
0.21
0.03
0.07
0.01
0.82
99.7
479
58na
279
0.60
8.10
0.77
0.26
1.27
6.07
10.5
70.
2017
.35
10.9
60.
980.
190.
020.
020.
020.
4399
.93
7959
na26
40.
377.
300.
710.
231.
156.
2110
.49
0.20
16.4
111
.94
0.95
0.21
0.04
0.02
0.01
0.43
100.
0978
56na
276
0.42
7.76
0.77
0.24
1.27
16.7
18.
620.
157.
8011
.53
2.07
0.51
0.05
0.02
0.02
0.93
99.9
168
36na
177
0.74
15.3
21.
180.
371.
9716
.74
8.12
0.15
7.72
11.4
42.
740.
480.
030.
020.
021.
1599
.89
6934
na16
70.
7814
.94
1.11
0.36
1.89
18.1
87.
420.
146.
6211
.69
2.56
0.54
0.05
0.04
0.01
1.71
100.
1667
31na
154
0.96
16.0
81.
260.
402.
0713
.99
6.97
0.14
11.0
512
.12
2.11
0.55
0.02
0.05
0.01
2.58
100.
3979
36na
196
1.38
15.6
60.
530.
160.
8613
.66
9.08
0.16
9.76
11.6
82.
200.
450.
120.
020.
021.
4099
.98
7141
na20
71.
0014
.60
1.26
0.39
2.06
5.85
10.7
20.
2117
.31
11.0
41.
010.
210.
04na
0.01
0.68
99.9
079
58na
265
0.43
7.58
0.78
0.26
1.29
18.6
07.
690.
136.
7111
.72
2.53
0.56
0.04
0.02
0.01
1.08
100.
2867
30na
158
0.76
18.1
51.
220.
392.
0613
.00
15.5
60.
234.
647.
192.
522.
050.
050.
190.
111.
2699
.59
4162
na44
00.
6610
0.07
2.77
0.86
4.82
11.0
415
.71
0.12
2.09
7.22
4.74
0.07
0.11
6.06
0.93
5.86
98.9
324
380
na71
0.22
0.78
8.24
18.3
05.
4414
.52
13.8
50.
224.
716.
763.
451.
600.
110.
290.
081.
5010
0.22
4452
7523
50.
4465
.46
4.42
1.41
5.41
12.7
814
.16
0.16
3.09
5.93
3.61
1.79
0.16
na0.
051.
9310
0.10
3441
na22
40.
7374
.19
6.81
2.11
12.0
915
.22
8.53
0.13
8.68
12.7
11.
660.
440.
030.
270.
052.
0810
0.35
7035
na21
00.
7116
.76
0.98
0.35
1.36
14.0
310
.46
0.19
8.49
12.0
21.
590.
460.
030.
170.
040.
3810
0.19
6545
na24
00.
8715
.66
1.32
0.37
2.07
14.3
89.
930.
178.
5712
.80
1.45
0.46
0.02
0.16
0.08
0.25
100.
2967
41na
230
0.75
12.9
61.
140.
341.
8212
.96
14.1
80.
167.
6910
.39
1.01
0.56
0.02
0.13
3.50
2.75
96.0
356
170
na19
01.
6021
.74
1.09
0.31
1.43
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB98
-225
AJB
98-2
28JB
98-2
29JB
98-2
30JB
98-2
31JB
98-2
39D
JB98
-239
EJB
98-2
39F
RK
-1R
K-2
RK
-3R
K-4
RK
-5R
K-7
RK
-8R
K-9
RK
-10
RK
-11
RK
-12
RK
-13
RK
-14
RK
-15
RK
-16
RK
-17
RK
-18
RK
-19
JB97
-50
JB97
-54A
JB97
-63
JB98
-122
JB97
-14
JB97
-15
JB97
-16
JB97
-43A
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
0.16
3.76
8.22
1.11
104.
404.
9728
.35
0.95
1.18
0.40
0.21
01.
500.
251.
7710
.59
0.37
1.18
0.15
1.10
0.16
0.14
3.10
6.87
0.93
136.
804.
0722
.42
0.66
1.12
0.39
0.22
21.
380.
251.
779.
780.
371.
070.
140.
960.
170.
173.
286.
980.
9811
2.50
4.23
24.7
80.
881.
190.
440.
210
1.49
0.26
1.83
10.4
80.
381.
100.
181.
040.
180.
163.
296.
970.
9612
1.70
4.25
24.4
10.
811.
150.
430.
210
1.30
0.26
1.61
9.83
0.35
1.07
0.15
1.06
0.16
0.21
3.75
8.14
1.09
100.
704.
6618
.10
0.49
1.15
0.39
0.24
01.
310.
211.
516.
040.
330.
900.
130.
980.
130.
176.
6413
.74
1.75
152.
206.
8646
.57
1.28
1.65
0.51
0.31
81.
800.
312.
0713
.81
0.47
1.32
0.19
1.26
0.20
0.16
5.42
11.1
71.
4018
1.40
6.01
39.7
41.
111.
550.
510.
318
1.72
0.30
2.06
13.7
30.
431.
320.
191.
290.
200.
176.
2612
.95
1.68
190.
706.
8143
.62
1.26
1.67
0.60
0.31
21.
910.
342.
2414
.35
0.49
1.38
0.21
1.46
0.21
na5.
8312
.62
1.61
4.60
6.78
na1.
951.
560.
360.
198
1.51
0.23
1.37
-0.
270.
840.
120.
770.
12na
3.76
8.00
1.00
245.
204.
30na
0.71
0.98
0.45
0.16
81.
090.
171.
10 -
0.22
0.65
0.09
0.61
0.09
na3.
898.
941.
164.
204.
94na
2.10
1.29
0.30
0.21
01.
370.
221.
33 -
0.27
0.81
0.11
0.77
0.12
na0.
120.
240.
03 -
0.14
na0.
240.
02 -
0.09
60.
020.
03 -
0.01
- -
-na
19.4
041
.38
5.18
237.
9022
.45
na4.
075.
421.
370.
713
5.72
0.88
5.47
-1.
103.
150.
432.
800.
42na
4.03
8.96
1.18
163.
905.
23na
1.13
1.37
0.47
0.25
81.
520.
241.
67 -
0.33
0.95
0.13
0.86
0.13
na4.
559.
651.
2313
3.70
5.53
na1.
191.
410.
460.
282
1.64
0.28
1.73
-0.
341.
000.
140.
890.
14na
3.40
7.36
0.96
67.6
04.
46na
1.23
1.25
0.37
0.24
61.
450.
241.
58 -
0.33
0.97
0.14
0.87
0.14
na3.
447.
520.
9870
.50
4.52
na1.
071.
240.
400.
246
1.47
0.25
1.58
-0.
330.
950.
130.
880.
14na
3.19
6.90
0.91
65.2
04.
19na
0.97
1.12
0.35
0.22
81.
300.
221.
46 -
0.30
0.88
0.12
0.78
0.12
na3.
467.
360.
9867
.80
4.51
na0.
981.
220.
380.
252
1.47
0.24
1.56
-0.
320.
950.
130.
850.
13na
5.42
11.3
81.
4522
0.80
6.37
na1.
341.
600.
570.
294
1.73
0.28
1.81
-0.
371.
050.
150.
940.
15na
5.34
11.2
01.
4222
5.70
6.17
na1.
301.
530.
580.
300
1.74
0.28
1.76
-0.
351.
000.
140.
900.
14na
5.59
11.3
81.
4023
6.80
6.16
na1.
351.
520.
600.
300
1.73
0.26
1.72
-0.
330.
990.
140.
890.
14na
2.56
5.51
0.72
204.
503.
29na
0.73
0.90
0.37
0.18
01.
070.
171.
14 -
0.23
0.67
0.09
0.64
0.10
na5.
6912
.04
1.54
171.
506.
73na
1.30
1.69
0.59
0.31
21.
870.
301.
94 -
0.39
1.14
0.16
1.03
0.15
na3.
417.
420.
9759
.00
4.48
na1.
081.
240.
370.
234
1.41
0.23
1.52
-0.
320.
960.
130.
650.
13na
5.59
11.4
31.
4324
9.10
6.42
na1.
351.
560.
620.
288
1.71
0.28
1.72
-0.
341.
020.
140.
690.
140.
3911
.41
25.1
73.
2314
8.00
14.3
6na
2.73
3.72
1.14
0.82
13.
870.
634.
08 -
0.84
2.36
0.34
2.20
0.32
0.50
250.
0025
0.00
30.9
933
.70
111.
81na
6.20
19.3
32.
020.
288
11.0
71.
155.
63 -
0.81
2.25
0.28
1.91
0.32
0.44
15.4
933
.69
4.15
186.
7017
.00
na3.
153.
841.
260.
653
4.16
0.70
3.94
-0.
882.
350.
342.
190.
350.
8925
.45
52.0
76.
5817
7.80
26.7
614
1.41
4.41
6.03
1.59
0.92
36.
281.
006.
5736
.90
1.27
3.72
0.53
3.33
0.54
0.09
4.31
9.78
1.26
168.
105.
55na
-1.
460.
510.
276
1.68
0.30
2.04
-0.
451.
330.
201.
300.
200.
145.
5812
.68
1.59
139.
106.
99na
-1.
860.
600.
336
2.07
0.36
2.48
-0.
551.
580.
231.
540.
220.
124.
9210
.81
1.38
121.
606.
27na
-1.
710.
540.
324
1.90
0.35
2.37
-0.
541.
550.
221.
480.
230.
104.
259.
351.
2011
8.50
5.36
na0.
951.
360.
500.
270
1.65
0.28
1.86
-0.
421.
200.
181.
170.
17
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
Tow
nshi
pSt
udy
Are
aD
escr
iptio
n 1
Roc
k T
ype
Fiel
d N
ame
JB97
-43B
Jane
sC
hini
guch
im
g; e
dge
of c
lear
ed a
rea
at w
est e
dge
of o
/c; F
alco
-tren
ches
opx
gabb
roJB
97-4
3CJa
nes
Chi
nigu
chi
mg;
eas
t edg
e of
cle
ared
are
a; F
alco
-tren
ches
opx
gabb
roJB
97-4
3DJa
nes
Chi
nigu
chi
mg;
on
edge
of h
igh
hill
to e
ast o
f cle
ared
are
a; F
alco
-tren
ches
opx
gabb
roJB
97-6
1W
ells
Bas
swoo
d Lk
Tra
vf.g
.-m.g
. gab
bro
- aug
ite p
heno
crys
ts?
opx
gabb
roJB
97-7
6BW
ater
sM
akad
afg
-mg
gabb
ro w
ith fe
lted
text
ure
opx
gabb
roJB
97-8
5AN
airn
Nai
rn W
right
mg;
ver
y m
afic
- m
elag
abbr
o?op
x ga
bbro
JB97
-95
Jane
sC
hini
guch
im
g; e
astw
ard
cont
inua
tion?
of T
1 tre
nch;
W e
dge
of ri
dge
east
of T
1op
x ga
bbro
JB97
-96
Jane
sC
hini
guch
im
g; fr
esh
blas
t - 2
pie
ces;
Bria
n to
ok 3
; bla
sted
are
a of
T1
opx
gabb
roJB
97-1
03A
Kel
lyK
ukag
ami D
etai
lm
g; P
GE-
rich
laye
r?; e
dge
of ri
dge
at b
ase
of b
last
ed p
it; S
edg
e of
ridg
eop
x ga
bbro
JB97
-103
BK
elly
Kuk
agam
i Det
ail
mg;
abo
ut 0
.6 m
"ab
ove"
103
Aop
x ga
bbro
JB97
-103
CK
elly
Kuk
agam
i Det
ail
mg;
abo
ut 1
.0 m
"ab
ove"
103
Aop
x ga
bbro
JB97
-103
DK
elly
Kuk
agam
i Det
ail
mg;
abo
ut 6
.0 m
eas
t of p
it ar
eaop
x ga
bbro
JB97
-106
BJa
nes
Chi
nigu
chi
Tren
ch T
-2 o
n Fa
lco
map
; abo
ut 2
3.0
m so
uth
of n
orth
end
of t
renc
h op
x ga
bbro
JB97
-107
Jane
sC
hini
guch
iE
of c
lear
ed a
rea
num
ber T
-4 o
n Fa
lcon
brid
ge m
ap; o
n to
p of
hill
;op
x ga
bbro
JB97
-108
Jane
sC
hini
guch
iE
of T
renc
h T-
4 on
Fal
co m
ap; 5
m b
elow
sam
ple
107
on ri
dge
opx
gabb
roJB
97-1
09Ja
nes
Chi
nigu
chi
sulp
h-ve
in a
t ~24
0az;
mel
agab
bro
in o
ld N
-S tr
ench
; upp
er a
rea
of T
4op
x ga
bbro
JB98
-123
Brid
glan
dB
assw
ood
Lk T
rav
mg;
N. s
ide
#129
; N. o
f Tw
p. L
ine;
wea
ther
s to
brow
n pi
ts (o
px?)
opx
gabb
roJB
98-1
47Lo
rne
Bel
l Lak
e Tr
avfg
-mg;
~75
m a
t 315
az fr
om st
at. 1
46 -
Trav
erse
opx
gabb
roJB
98-1
82C
urtin
Cha
rlton
Lk
Clif
fm
g; ~
15m
NW
of s
tat.
181;
~50
m E
of s
hore
; tra
vers
eop
x ga
bbro
JB98
-204
Kel
lyC
araf
el B
ay T
rav
mg;
mt-b
earin
g; o
n hi
gh c
liff w
est o
f lak
e ov
erlo
okin
g va
lley-
trave
rse
opx
gabb
roJB
98-2
12A
Loui
seLo
uie
Lake
mg;
smal
l pit
east
of l
arge
r and
mai
n pi
t are
aop
x ga
bbro
JB97
-37
Fost
erB
razi
l Lak
em
g; ~
75m
wes
t of t
renc
h; h
ighl
y fr
actu
red
- loc
ally
c.g
. to
near
peg
.le
ucog
abbr
oJB
97-4
7Er
mat
inge
rFo
x La
ke R
oad
in A
rche
an; m
g ga
bbro
; up
to 3
0% e
pido
tele
ucog
abbr
oJB
97-7
9BW
ater
sM
akad
afg
gab
bro
from
o/c
on
wes
t sid
e of
road
- hi
ll of
gab
bro;
grid
230
N/1
60E
leuc
ogab
bro
JB97
-104
Jane
sC
hini
guch
im
g; lo
catio
ns o
n Fa
lcon
brid
ge m
ap; o
n to
p of
hill
tow
ard
sout
heas
t edg
ele
ucog
abbr
oJB
98-1
15Ja
nes
Sarg
esso
nm
g; c
py>p
o>pn
in 3
40 A
z tre
ndin
g rid
ge o
f gab
bro
leuc
ogab
bro
JB98
-165
Wat
ers
Mak
ada
Det
ail
mg;
det
ail g
rid: 0
+2.5
S/0
+25
E; ~
20%
blu
e qt
z ey
esle
ucog
abbr
oJB
97-7
1Lo
uise
Lo
uie
Lake
mg
gabb
ro; s
outh
side
of l
arge
exp
ansi
ve o
/cm
elag
abbr
oJB
97-8
0ALo
uise
Loui
e La
kem
g; fe
lsic
gab
bro
from
wes
t sid
e of
hill
- no
n-m
tm
elag
abbr
oJB
97-8
3Lo
uise
Loui
e La
kem
g; sm
all m
afic
gab
bro
"pod
" at
SE
edge
of h
ill; a
rea
of v
cg to
nea
r-pe
g ga
bbro
mel
agab
bro
JB97
-84E
Loui
seLo
uie
Lake
mg;
nea
r mel
agab
bro;
alte
red
to fe
lty te
xtur
em
elag
abbr
oJB
98-1
97K
elly
Car
afel
Bay
Tra
vm
g; m
t-bea
ring;
~40
m N
. of l
ast s
tatio
n - T
rave
rse
mt g
abbr
oJB
98-1
24K
irkw
ood
Bas
swoo
d Lk
Tra
vfg
-mg;
E. s
ide
#129
; pos
sibl
y qt
z-ga
bbro
; bec
omes
mor
e fg
sout
h al
ong
o/c
qtz
gabb
roJB
98-1
46Lo
rne
Bel
l Lak
e Tr
avm
g; ~
50m
at 3
15az
from
stat
. 145
- Tr
aver
seqt
z ga
bbro
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-43B
JB97
-43C
JB97
-43D
JB97
-61
JB97
-76B
JB97
-85A
JB97
-95
JB97
-96
JB97
-103
AJB
97-1
03B
JB97
-103
CJB
97-1
03D
JB97
-106
BJB
97-1
07JB
97-1
08JB
97-1
09JB
98-1
23JB
98-1
47JB
98-1
82JB
98-2
04JB
98-2
12A
JB97
-37
JB97
-47
JB97
-79B
JB97
-104
JB98
-115
JB98
-165
JB97
-71
JB97
-80A
JB97
-83
JB97
-84E
JB98
-197
JB98
-124
JB98
-146
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
none
vis
ible
0.04
020
1.0
140
0.27
00.
660
0.61
010
.370
20.2
603.
790
110
276
51.1
10.
54d.
s. po
=cpy
2.71
016
732.
043
001.
300
7.19
012
.280
284.
500
1577
.320
352.
750
1100
029
546
.19
0.43
d.s.
po=c
py0.
390
2757
.072
00.
250
1.11
01.
190
35.4
5080
.030
45.9
2016
0038
649
.63
0.39
none
0.07
045
7.0
118
0.27
00.
660
0.26
01.
430
1.88
05.
040
786
947
.69
2.70
d.s.
- po>
cpy
0.80
011
34.0
210
0.27
00.
660
0.57
05.
460
5.37
03.
220
220
187
53.1
90.
74d.
s. an
d b.
s.9.
400
3967
5.0
7153
1.55
01.
440
1.46
032
.500
21.4
0016
.050
2758
3na
nana
nacp
y, p
o, p
n?0.
450
3525
.086
80.
270
0.66
00.
260
35.1
1066
.090
44.3
7019
0832
550
.28
0.44
cpy,
po,
pn
3.02
018
285.
049
411.
320
3.77
017
54.7
5034
5.10
071
35.6
1040
4.25
013
069
nana
nana
d.s a
nd b
.s. -
look
mag
mat
ic1.
734
6400
.027
730.
700
0.66
023
.000
380.
000
1930
.000
120.
000
5095
305
48.5
80.
41d.
s.0.
067
700.
021
30.
500
0.66
00.
700
20.0
0055
.000
2.00
019
628
550
.78
0.44
d.s.
and
b.s.
1.96
162
00.0
2662
0.80
00.
660
12.0
0044
0.00
015
50.0
0012
0.00
062
5929
548
.23
0.42
d.s.
0.06
760
0.0
148
0.20
00.
660
1.10
012
.000
19.0
001.
000
110
276
50.3
40.
51d.
s.0.
049
400.
012
10.
200
0.66
00.
200
11.0
0018
.000
2.70
071
256
49.5
10.
56d.
s.; w
ith <
1% m
agne
tite
0.04
420
0.0
178
0.20
00.
660
0.90
028
.000
61.0
003.
700
129
375
49.8
90.
39b.
s. an
d d.
s.0.
035
500.
014
90.
200
0.66
00.
600
11.0
0015
.000
0.80
087
335
50.9
00.
43d.
s. an
d b.
s. 5.
323
3519
0.0
1056
02.
400
0.66
023
.000
1300
.000
4560
.000
720.
000
1708
024
742
.57
0.55
none
vis
ible
0.03
820
1.0
130
0.09
90.
263
0.42
531
.500
33.2
006.
000
9238
650
.90
0.41
none
0.00
515
.035
51.
077
1.68
03.
070
10.5
902.
260
0.73
06
193
51.1
70.
24d.
s. &
b.s.
; po>
cpy;
2m
x2m
0.08
542
2.0
166
0.27
00.
270
0.12
63.
150
3.01
02.
350
295
295
50.1
70.
41pa
tchy
mag
netis
m (p
o?)
0.00
910
0.0
147
0.05
60.
150
0.40
78.
540
8.72
01.
970
7830
551
.72
0.48
po a
nd c
py a
s d.s.
and
b.s.
2.77
029
06.0
502
0.26
60.
530
0.61
010
.320
13.6
5044
.600
546
103
49.8
70.
65no
ne v
isib
le0.
070
300.
083
0.27
00.
660
0.23
01.
430
1.88
02.
320
130
268
52.0
40.
55no
ne0.
050
270.
078
0.27
00.
660
0.26
01.
430
1.93
01.
420
170
169
52.1
70.
89no
ne v
isib
le0.
010
73.0
212
0.27
00.
660
0.26
05.
050
10.3
201.
420
5332
551
.81
0.42
d.s.
0.05
950
0.0
190
0.27
00.
660
0.60
011
.000
6.00
011
.000
250
415
49.8
20.
32bl
eb a
nd d
iss.
0.77
056
83.0
1116
0.25
50.
380
1.01
210
1.00
011
6.60
015
7.30
032
1730
649
.89
0.45
po>>
cpy
as d
.s./b
.s.14
.500
80.0
3062
0.74
41.
830
5.02
018
.770
30.5
0023
8.00
017
0229
741
.70
0.21
none
vis
ible
0.05
024
8.0
162
0.27
00.
660
0.26
06.
320
5.48
03.
830
151
545
49.8
60.
27no
ne v
isib
le0.
040
258.
016
60.
270
0.66
00.
260
20.2
7024
.670
3.30
010
635
550
.86
0.40
b.s.
and
d.s.
- bre
ccia
?9.
880
59.0
1490
0.27
01.
600
1.77
026
.560
28.2
6063
.420
874
nana
nana
po>c
py>p
y>pn
22.8
0026
685.
039
391.
800
6.09
05.
660
11.1
6045
.370
4.67
066
8na
nana
nam
ainl
y po
; 5%
mag
netit
e?0.
058
243.
063
0.27
00.
660
0.26
01.
430
0.09
00.
820
118
189
52.9
20.
80no
ne v
isib
le0.
052
269.
010
90.
270
0.22
00.
260
10.0
7011
.450
3.02
010
826
751
.86
0.57
none
0.01
811
4.0
188
0.10
10.
580
0.53
04.
820
6.45
01.
540
5530
551
.20
0.47
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-43B
JB97
-43C
JB97
-43D
JB97
-61
JB97
-76B
JB97
-85A
JB97
-95
JB97
-96
JB97
-103
AJB
97-1
03B
JB97
-103
CJB
97-1
03D
JB97
-106
BJB
97-1
07JB
97-1
08JB
97-1
09JB
98-1
23JB
98-1
47JB
98-1
82JB
98-2
04JB
98-2
12A
JB97
-37
JB97
-47
JB97
-79B
JB97
-104
JB98
-115
JB98
-165
JB97
-71
JB97
-80A
JB97
-83
JB97
-84E
JB98
-197
JB98
-124
JB98
-146
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
14.6
29.
460.
178.
2012
.32
1.41
0.48
0.03
0.31
0.04
2.12
100.
4667
37na
210
1.24
18.0
91.
360.
401.
9212
.48
14.3
00.
178.
4710
.81
1.41
0.16
0.02
0.12
2.71
2.02
96.4
658
140
na19
00.
554.
121.
060.
301.
2014
.84
8.50
0.13
8.85
13.1
71.
320.
340.
020.
390.
392.
0599
.24
7150
na18
01.
269.
840.
860.
261.
0615
.12
15.3
70.
195.
437.
563.
191.
480.
550.
090.
070.
5599
.83
4557
117
241
1.98
36.1
22.
810.
8414
.94
13.5
59.
060.
077.
588.
964.
080.
450.
130.
370.
801.
2999
.10
6640
na23
00.
309.
450.
982.
549.
42na
nana
nana
nana
na0.
299.
40na
0.00
-17
817
994
0.66
4.91
10.3
26.
006.
8013
.91
9.32
0.16
9.41
12.7
11.
240.
550.
040.
180.
451.
3899
.44
7056
500
195
2.57
18.8
30.
100.
301.
28na
nana
nana
nana
na0.
103.
02na
0.00
-16
239
018
90.
807.
781.
080.
321.
1412
.42
11.9
80.
179.
1512
.27
1.12
0.34
0.05
na1.
732.
1098
.59
64na
na20
21.
2512
.38
0.97
0.29
1.62
12.3
79.
920.
1710
.47
13.2
01.
460.
340.
06na
0.07
0.99
100.
2071
nana
214
1.12
12.1
50.
920.
291.
4612
.01
11.8
10.
169.
5212
.25
0.36
0.36
0.06
na1.
962.
5597
.73
65na
na19
91.
9713
.73
1.05
0.32
1.51
13.6
010
.07
0.18
9.15
12.3
41.
420.
610.
04na
0.07
1.88
100.
1468
nana
209
2.66
19.7
31.
200.
392.
4214
.19
10.5
30.
178.
3610
.94
1.99
0.41
0.05
na0.
053.
5610
0.27
65na
na19
30.
5613
.54
1.23
0.40
1.76
14.4
38.
600.
149.
2813
.43
1.25
0.53
0.05
na0.
041.
9899
.97
72na
na19
32.
0113
.09
0.79
0.23
1.36
14.0
69.
530.
159.
2612
.72
1.08
0.49
0.05
na0.
040.
8599
.52
69na
na20
40.
8312
.55
0.94
0.29
1.49
13.0
316
.64
0.13
6.03
5.69
2.43
0.11
0.07
na5.
324.
5191
.76
4628
3na
191
0.42
1.86
3.34
1.09
2.65
15.4
08.
360.
159.
1212
.63
2.10
0.32
0.03
na0.
040.
6810
0.10
7236
na18
10.
4710
.02
0.97
0.30
1.46
4.47
9.70
0.22
19.4
110
.87
0.86
0.04
0.01
na0.
005
3.27
100.
2682
73na
225
0.15
1.43
0.38
0.15
1.01
12.0
49.
840.
1810
.48
10.4
12.
120.
680.
03na
0.09
3.82
100.
1871
49na
214
1.12
22.3
11.
160.
391.
5414
.45
9.06
0.17
9.44
12.6
41.
590.
370.
03na
0.01
0.35
100.
3071
44na
217
0.78
13.1
61.
150.
371.
706.
2117
.57
0.24
15.0
76.
670.
270.
060.
05na
2.77
3.51
100.
1767
134
na20
60.
354.
242.
080.
622.
7914
.55
11.0
10.
196.
7210
.54
1.98
0.67
0.03
0.16
0.07
1.26
99.5
459
42na
230
1.26
22.7
21.
500.
462.
1013
.88
12.8
90.
205.
799.
912.
400.
490.
020.
240.
051.
0299
.66
5158
na30
00.
9021
.85
2.41
0.68
5.21
13.5
98.
690.
1410
.72
11.6
21.
720.
520.
030.
130.
011.
2410
0.50
7442
500
219
1.62
22.9
10.
960.
301.
5513
.19
9.20
0.15
10.4
812
.33
0.64
0.32
0.04
na0.
063.
7510
0.24
73na
na18
50.
869.
630.
710.
221.
0913
.36
10.8
10.
188.
9910
.56
1.72
0.54
0.03
na0.
773.
1899
.71
6672
na20
30.
7619
.58
1.15
0.36
1.70
6.10
32.4
30.
035.
591.
210.
861.
130.
02na
14.5
07.
4796
.75
2945
7na
922.
2152
.84
5.36
2.42
2.40
14.6
78.
150.
169.
9612
.29
1.38
0.68
0.02
0.36
0.05
2.54
99.9
874
4031
717
40.
8626
.37
0.53
0.16
0.68
14.0
38.
470.
169.
8312
.42
1.57
0.74
0.03
0.20
0.04
1.56
100.
0773
3850
019
21.
2318
.10
0.79
0.25
1.20
nana
nana
nana
nana
0.10
9.88
na0.
00-
405
500
105
0.17
1.71
2.62
1.29
1.36
nana
nana
nana
nana
0.12
22.8
0na
0.00
-10
9150
099
0.97
7.48
0.43
0.15
0.67
14.0
612
.19
0.21
6.01
9.95
2.11
0.77
0.08
na0.
060.
9110
0.01
5346
na27
52.
1828
.19
2.33
0.70
3.31
14.6
09.
800.
157.
7011
.01
2.03
0.83
0.05
na0.
051.
6210
0.22
6543
na22
31.
2030
.32
1.66
0.50
2.38
14.0
68.
340.
159.
9311
.35
2.16
0.31
0.02
na0.
018
2.33
100.
3273
45na
215
0.87
11.6
71.
270.
361.
96
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-43B
JB97
-43C
JB97
-43D
JB97
-61
JB97
-76B
JB97
-85A
JB97
-95
JB97
-96
JB97
-103
AJB
97-1
03B
JB97
-103
CJB
97-1
03D
JB97
-106
BJB
97-1
07JB
97-1
08JB
97-1
09JB
98-1
23JB
98-1
47JB
98-1
82JB
98-2
04JB
98-2
12A
JB97
-37
JB97
-47
JB97
-79B
JB97
-104
JB98
-115
JB98
-165
JB97
-71
JB97
-80A
JB97
-83
JB97
-84E
JB98
-197
JB98
-124
JB98
-146
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
0.13
5.48
12.1
41.
5513
8.30
6.78
na1.
101.
790.
600.
324
2.00
0.34
2.36
-0.
491.
440.
221.
460.
210.
104.
189.
141.
1910
7.00
5.20
na0.
871.
390.
480.
258
1.62
0.28
1.84
-0.
401.
190.
171.
090.
160.
083.
547.
841.
0113
9.80
4.43
na0.
801.
230.
430.
234
1.51
0.26
1.72
-0.
391.
090.
161.
070.
150.
8828
.30
64.5
18.
2937
2.20
35.8
2na
5.81
7.87
2.61
1.61
97.
631.
266.
77 -
1.47
3.95
0.57
3.67
0.54
0.83
4.43
12.7
02.
1118
0.70
10.5
2na
1.31
3.28
0.57
0.44
43.
430.
614.
08 -
0.87
2.34
0.34
1.98
0.28
0.92
37.1
477
.55
8.67
224.
7031
.47
na4.
396.
161.
80 -
5.48
0.90
4.64
-0.
962.
430.
352.
080.
320.
112.
716.
940.
9210
8.80
4.08
na0.
481.
160.
380.
264
1.38
0.25
1.62
-0.
360.
990.
141.
000.
150.
104.
219.
521.
2211
8.90
5.23
na1.
071.
360.
48 -
1.62
0.29
1.86
-0.
421.
230.
181.
210.
18na
4.34
9.56
1.25
107.
605.
4933
.60
1.01
1.50
0.49
0.24
61.
800.
312.
0712
.91
0.46
1.34
0.20
1.30
0.20
na4.
159.
011.
1711
6.70
5.21
33.7
91.
001.
450.
490.
264
1.78
0.31
2.11
12.8
90.
461.
380.
201.
300.
20na
4.33
9.21
1.18
116.
005.
2435
.17
1.03
1.41
0.47
0.25
21.
710.
302.
0212
.35
0.43
1.31
0.19
1.23
0.19
na5.
2211
.13
1.41
141.
506.
1842
.36
1.22
1.66
0.53
0.30
62.
000.
342.
3614
.16
0.50
1.49
0.22
1.45
0.22
na5.
5211
.79
1.47
155.
206.
2842
.04
1.18
1.64
0.54
0.33
61.
900.
332.
2513
.79
0.49
1.41
0.20
1.34
0.21
na3.
597.
670.
9813
5.60
4.30
28.4
40.
831.
150.
420.
234
1.46
0.25
1.72
10.7
10.
381.
080.
161.
050.
16na
4.02
8.70
1.12
138.
304.
9532
.90
0.97
1.36
0.46
0.25
81.
700.
291.
9612
.18
0.42
1.26
0.18
1.15
0.18
na9.
5920
.51
2.42
291.
809.
1135
.64
1.27
2.00
0.52
0.33
01.
930.
312.
0911
.75
0.44
1.26
0.17
1.19
0.18
0.19
4.06
8.66
1.16
130.
005.
0130
.96
0.99
1.32
0.51
0.24
61.
660.
301.
8911
.94
0.43
1.19
0.16
1.11
0.17
0.14
1.40
3.35
0.63
8.10
3.21
21.0
50.
590.
920.
310.
144
1.05
0.18
1.15
7.30
0.25
0.72
0.10
0.70
0.09
0.17
4.76
9.80
1.29
144.
005.
3531
.57
1.06
1.58
0.47
0.24
61.
590.
292.
0111
.91
0.43
1.28
0.19
1.28
0.20
0.19
5.12
10.5
11.
3813
6.20
6.10
35.8
11.
141.
580.
530.
288
1.84
0.34
2.12
13.4
70.
471.
300.
191.
180.
200.
265.
5012
.26
1.55
3.70
6.90
52.9
21.
771.
700.
360.
390
2.06
0.36
2.36
14.2
70.
541.
640.
241.
580.
240.
156.
0713
.06
1.62
148.
807.
01na
1.24
1.84
0.62
0.33
02.
050.
342.
22 -
0.52
1.48
0.22
1.49
0.21
0.27
8.48
18.8
02.
4622
5.50
10.7
0na
2.17
2.80
0.96
0.53
42.
830.
483.
20 -
0.67
1.84
0.26
1.77
0.26
0.15
3.49
8.17
1.08
169.
604.
85na
1.03
1.28
0.48
0.25
21.
480.
261.
60 -
0.34
1.03
0.14
0.85
0.13
na3.
146.
680.
8713
7.40
3.83
25.3
50.
701.
050.
360.
192
1.32
0.22
1.55
9.66
0.33
0.99
0.14
0.94
0.14
0.18
4.73
10.0
71.
3314
1.00
5.74
38.7
91.
171.
550.
490.
270
1.79
0.30
2.25
14.1
80.
461.
340.
181.
380.
190.
349.
0618
.05
2.14
33.3
08.
4410
2.89
3.19
1.50
0.28
0.12
61.
250.
201.
227.
080.
220.
750.
110.
800.
110.
062.
405.
400.
7013
3.10
3.07
na0.
750.
780.
370.
162
1.02
0.19
1.26
-0.
290.
820.
120.
830.
120.
123.
668.
381.
0915
6.20
5.37
na1.
011.
260.
460.
240
1.49
0.27
1.74
-0.
401.
180.
161.
110.
160.
151.
734.
820.
652.
402.
85na
1.76
0.85
0.18
-0.
870.
150.
85 -
0.19
0.59
0.09
0.65
0.11
0.06
1.66
4.16
0.45
7.30
1.87
na0.
520.
440.
11 -
0.50
0.09
0.61
-0.
140.
460.
060.
460.
070.
309.
7819
.81
2.57
170.
1010
.84
65.4
52.
212.
740.
900.
480
3.05
0.55
3.58
22.4
90.
812.
190.
322.
200.
330.
246.
3913
.20
1.75
163.
107.
4446
.62
1.53
1.87
0.67
0.34
22.
230.
392.
6216
.39
0.58
1.75
0.24
1.61
0.25
0.23
5.13
10.9
91.
4919
3.10
6.09
37.5
21.
111.
550.
540.
282
1.64
0.26
1.93
10.9
40.
371.
060.
150.
920.
16
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
Tow
nshi
pSt
udy
Are
aD
escr
iptio
n 1
Roc
k T
ype
Fiel
d N
ame
JB97
-19A
Kel
lyW
asha
gam
i Lak
em
g; m
iner
aliz
atio
n a/
w p
enet
rativ
e fr
actu
re sy
stem
; cle
ared
o/c
wes
t sid
e of
val
ley
vt g
abbr
oJB
97-1
9BK
elly
Was
haga
mi L
ake
pegm
atoi
dal g
abbr
o in
are
a; n
o m
iner
aliz
atio
n ~2
m n
orth
of 1
9Avt
gab
bro
JB97
-38
Fost
erB
razi
l Lak
em
g; 1
5m e
ast o
f tre
nch;
var
i-tex
ture
d; h
ighl
y fr
actu
red
vt g
abbr
oJB
97-4
5M
oncr
ieff
Gen
eva
Lake
in A
rche
an; "
vari-
text
" ga
bbro
; up
to 3
0% e
pido
tevt
gab
bro
JB97
-51
Wel
lsA
pple
by L
k Tr
avA
pple
by L
k; m
g-vc
g ga
bbro
; var
i-tex
t. w
mic
ro-p
egm
atite
vt g
abbr
oJB
97-5
2W
ells
App
leby
Lk
Trav
App
leby
Lk;
mg-
vcg
gabb
ro; v
ari-t
ext.
w m
icro
-peg
mat
itevt
gab
bro
JB97
-53
Wel
lsA
pple
by L
k Tr
avA
pple
by L
k; m
g-vc
g ga
bbro
; var
i-tex
t. w
mic
ro-p
egm
atite
vt g
abbr
oJB
97-5
9W
ells
Bas
swoo
d Lk
Tra
vM
issi
ssag
i Riv
er; m
g-cg
gab
ro; l
ocal
ly v
cg to
mic
ro-p
eg.;
road
cut
on
way
to D
amvt
gab
bro
JB97
-60
Wel
lsB
assw
ood
Lk T
rav
Mis
siss
agi R
iver
; mg-
cg g
abro
; loc
ally
vcg
to m
icro
-peg
.; ro
ad c
ut o
n w
ay to
Dam
vt g
abbr
oJB
97-6
4W
ells
Bas
swoo
d Lk
Tra
vm
g-cg
; loc
ally
vcg
to m
icro
-peg
.;aci
cula
r am
ph.;
pink
fspa
rvt
gab
bro
JB97
-66
Wel
lsB
assw
ood
Lk T
rav
m.g
. gab
bro;
lim
ited
patc
hes o
f pin
k fs
par a
nd m
icro
-peg
.vt
gab
bro
JB97
-98
Scad
ding
Scad
ding
mg;
d.s.
& b
leb
sulp
hide
; eas
t sid
e of
Kuk
agam
i Lk.
Rd.
- ne
wly
bla
sted
o/c
vt g
abbr
oJB
97-1
00Sc
addi
ngSc
addi
ngm
g; n
r. "G
arba
ge D
ump
Rd"
-Fe-
carb
-Au?
; bas
e of
hill
; var
i-tex
t. to
hill
top
vt g
abbr
oJB
97-1
05Ja
nes
Chi
nigu
chi
peg-
vari-
text
. gab
bro;
pat
ches
of f
elte
d am
phib
ole;
on
hillt
opvt
gab
bro
JB98
-119
Wel
lsB
assw
ood
Lk T
rav
mg;
W o
f HW
Y#1
29;
30%
pin
k fs
par;
pegm
atiti
c po
ds; g
rano
phyr
ic g
abbr
ovt
gab
bro
JB98
-120
Wel
lsB
assw
ood
Lk T
rav
mg;
E o
f HW
Y#1
29; p
egm
atiti
c an
d an
orth
ositi
c pa
rts; g
rano
phyr
ic g
abbr
ovt
gab
bro
JB98
-121
AW
ells
Bas
swoo
d Lk
Tra
vm
g; N
. sid
e of
HW
Y#1
29; l
ocal
ly p
eg. w
eath
ers d
eep
red-
brow
nvt
gab
bro
JB98
-121
BW
ells
Bas
swoo
d Lk
Tra
vm
g; S
. sid
e of
HW
Y#1
29; g
ener
ally
sam
e as
121
A b
ut c
ut b
y cp
y-qt
z ve
ins
vt g
abbr
o
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-19A
JB97
-19B
JB97
-38
JB97
-45
JB97
-51
JB97
-52
JB97
-53
JB97
-59
JB97
-60
JB97
-64
JB97
-66
JB97
-98
JB97
-100
JB97
-105
JB98
-119
JB98
-120
JB98
-121
AJB
98-1
21B
Sulp
hide
/Oxi
deS
SeN
iIr
Ru
Rh
PtPd
Au
Cu
Al2
O3
SiO
2Si
O2
TiO
2w
t%pp
bpp
mpp
bpp
bpp
bpp
bpp
bpp
bpp
mTi
O2
MgO
wt%
wt%
d.s.
and
cpy
strin
gers
0.04
032
1.0
220
0.17
00.
660
0.79
017
.830
68.7
7017
.090
190
335
50.1
20.
42bl
eb a
nd d
.s.0.
070
297.
017
00.
170
0.66
00.
880
16.0
5057
.410
4.33
015
032
650
.73
0.46
none
vis
ible
0.03
014
1.0
850.
270
0.66
00.
160
1.43
01.
690
2.08
066
307
51.4
40.
51no
ne v
isib
le0.
140
428.
044
0.27
00.
660
0.48
01.
430
1.88
06.
670
190
615
51.9
71.
95no
ne0.
160
345.
027
0.27
00.
660
0.26
01.
430
1.88
03.
410
656
2053
.67
2.04
none
0.12
041
1.0
600.
270
0.66
00.
260
1.43
01.
880
2.50
019
09
1250
.62
1.40
d.s.
0.10
013
95.0
780.
270
0.66
00.
260
1.43
01.
880
3.47
016
012
1052
.13
1.10
up to
5%
mag
netit
e0.
110
410.
057
0.27
00.
660
0.26
01.
430
1.88
04.
070
160
1011
52.4
31.
29up
to 5
% m
agne
tite
0.10
066
.063
0.27
00.
660
0.26
01.
270
1.65
01.
090
160
1111
52.4
21.
25no
ne0.
080
361.
044
0.27
00.
660
0.26
01.
430
1.88
07.
600
217
718
53.2
21.
98no
ne0.
050
288.
044
0.27
00.
660
0.26
01.
430
1.88
06.
440
111
617
52.5
52.
27bl
ebs
0.06
840
0.0
114
0.20
00.
660
0.26
014
.000
5.00
02.
200
162
266
49.7
90.
54no
ne v
isib
le0.
042
300.
014
00.
400
0.66
00.
500
11.0
0014
.000
2.10
086
246
49.8
10.
58d.
s.0.
022
200.
013
50.
500
0.66
01.
400
30.0
0040
.000
1.80
077
476
49.4
10.
34no
ne0.
061
294.
060
0.27
00.
140
0.26
01.
430
0.12
11.
340
279
815
52.7
21.
71no
ne0.
016
206.
056
0.27
00.
170
0.26
07.
170
0.98
87.
360
175
1014
53.7
61.
35cp
y, p
y>po
0.04
489
.034
0.38
112
.080
7.84
01.
430
0.20
41.
160
498
1455
.21
1.52
d.s.
and
b.s.;
"m
afic
" ga
bbro
4.12
090
56.0
600.
270
0.66
00.
260
1.43
00.
079
4.19
047
695
853
.18
1.89
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-19A
JB97
-19B
JB97
-38
JB97
-45
JB97
-51
JB97
-52
JB97
-53
JB97
-59
JB97
-60
JB97
-64
JB97
-66
JB97
-98
JB97
-100
JB97
-105
JB98
-119
JB98
-120
JB98
-121
AJB
98-1
21B
Al2
O3
Fe2O
3*M
nOM
gOC
aON
a2O
K2O
P2O
5C
O2
SL
OI
M-T
otal
Mg#
Co
Cr*
VC
sR
bT
hU
Nb
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
wt%
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
13.8
29.
200.
199.
8612
.13
1.18
0.28
0.01
0.14
0.04
2.81
100.
0271
39na
200
0.16
2.92
0.80
0.25
1.06
14.8
98.
240.
168.
6212
.62
1.32
0.83
0.02
0.21
0.07
2.10
99.9
971
36na
200
1.70
31.2
41.
000.
301.
2715
.40
9.17
0.10
7.30
9.21
2.93
1.26
0.03
0.31
0.03
2.25
99.6
065
33na
180
0.66
32.8
61.
610.
542.
1312
.19
18.0
90.
223.
456.
483.
240.
840.
090.
090.
141.
0399
.55
3164
na57
00.
4633
.91
3.93
1.18
7.06
12.2
818
.51
0.19
2.70
4.09
4.43
1.04
0.09
0.18
0.16
0.63
99.6
725
54na
320
0.22
46.1
04.
591.
588.
0513
.05
17.6
50.
264.
194.
753.
231.
750.
050.
300.
121.
6498
.59
3665
na44
00.
4075
.45
3.04
0.92
5.11
13.3
913
.98
0.22
5.09
7.59
2.57
1.81
0.05
0.19
0.10
1.46
99.3
946
57na
300
0.66
78.9
32.
640.
824.
9213
.15
15.3
30.
214.
608.
582.
461.
090.
050.
150.
110.
6499
.83
4158
na38
02.
2850
.90
2.85
0.89
5.14
13.1
714
.96
0.20
4.85
8.77
2.40
1.05
0.05
0.13
0.10
0.73
99.8
543
56na
370
1.72
41.3
92.
920.
865.
1113
.04
15.5
40.
183.
046.
763.
251.
660.
150.
100.
081.
0699
.88
3150
4631
00.
2243
.02
5.29
1.72
7.91
13.3
815
.71
0.19
3.13
6.68
3.56
1.29
0.13
0.06
0.05
1.16
100.
0532
4963
528
0.52
54.6
06.
372.
027.
1814
.23
10.6
80.
198.
1010
.76
1.75
0.76
0.06
na0.
073.
4310
0.29
64na
na19
40.
8627
.52
0.92
0.28
1.67
13.6
910
.49
0.14
8.85
11.3
71.
300.
850.
08na
0.04
3.14
100.
3066
nana
203
0.30
31.5
61.
010.
322.
0415
.82
7.70
0.15
8.45
13.1
61.
470.
320.
04na
0.02
3.17
100.
0372
nana
166
0.56
11.1
20.
700.
211.
2513
.36
14.3
90.
173.
557.
362.
921.
140.
15na
0.06
2.20
99.6
736
53na
511
0.52
46.1
65.
451.
756.
8713
.36
13.3
30.
203.
827.
132.
981.
670.
13na
0.02
2.04
99.7
740
48na
264
0.59
75.1
15.
471.
647.
3812
.51
14.3
40.
223.
813.
823.
431.
660.
18na
0.04
2.96
99.6
638
47na
237
0.95
58.5
76.
992.
289.
0510
.12
21.6
50.
086.
340.
730.
460.
040.
18na
4.12
4.16
98.8
341
61na
176
0.32
1.36
11.2
76.
7216
.82
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sam
ple
JB97
-19A
JB97
-19B
JB97
-38
JB97
-45
JB97
-51
JB97
-52
JB97
-53
JB97
-59
JB97
-60
JB97
-64
JB97
-66
JB97
-98
JB97
-100
JB97
-105
JB98
-119
JB98
-120
JB98
-121
AJB
98-1
21B
Ta
La
Ce
PrSr
Nd
Zr
Hf
SmE
uT
i*G
dT
bD
yY
Ho
Er
Tm
Yb
Lu
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
ppm
0.08
5.66
12.2
71.
4717
3.30
6.39
na -
1.64
0.52
0.25
21.
770.
302.
00 -
0.47
1.30
0.19
1.23
0.17
0.08
4.19
9.53
1.20
162.
805.
42na
-1.
430.
490.
276
1.60
0.28
2.00
-0.
451.
320.
191.
200.
180.
155.
8712
.33
1.45
189.
605.
98na
1.05
1.39
0.53
0.30
61.
430.
241.
62 -
0.37
1.08
0.15
1.03
0.16
0.52
16.1
835
.82
4.65
220.
4020
.28
na3.
344.
981.
491.
169
5.13
0.84
5.49
-1.
093.
020.
432.
860.
410.
5418
.11
39.6
15.
0312
5.50
21.7
9na
4.21
5.24
1.67
1.22
35.
250.
885.
63 -
1.20
3.20
0.48
3.15
0.46
0.36
11.3
324
.88
3.28
122.
5014
.31
na2.
813.
751.
110.
839
3.80
0.64
4.06
-0.
852.
370.
342.
260.
350.
3510
.99
24.3
73.
1417
6.30
13.9
6na
2.74
3.62
1.09
0.65
93.
640.
613.
93 -
0.83
2.30
0.35
2.24
0.34
0.53
11.6
225
.69
3.35
196.
0014
.84
na2.
703.
671.
200.
773
3.92
0.65
4.08
-0.
852.
400.
342.
250.
330.
4111
.73
26.1
13.
3721
9.40
15.0
4na
2.99
3.79
1.13
0.74
93.
890.
644.
19 -
0.86
2.42
0.35
2.32
0.33
0.59
19.0
742
.09
5.18
141.
5020
.78
na4.
044.
741.
271.
187
4.97
0.81
4.68
-1.
042.
730.
402.
630.
390.
9521
.72
46.3
55.
7116
9.80
22.7
9na
4.16
5.03
1.43
1.36
15.
300.
885.
06 -
1.08
2.96
0.40
2.61
0.40
na4.
439.
541.
2426
7.90
5.56
33.8
60.
981.
500.
560.
324
1.72
0.28
1.82
10.2
20.
371.
050.
150.
950.
14na
4.52
9.94
1.31
160.
105.
9840
.32
1.19
1.68
0.59
0.34
81.
950.
322.
0512
.12
0.42
1.25
0.17
1.15
0.17
na3.
206.
820.
8717
4.40
3.93
26.5
90.
761.
080.
380.
204
1.33
0.22
1.58
9.79
0.33
0.99
0.14
0.94
0.15
0.57
20.1
140
.91
5.29
243.
4021
.60
119.
693.
714.
881.
451.
025
4.92
0.76
5.03
28.7
81.
012.
910.
382.
500.
390.
5619
.78
41.2
65.
4221
7.10
22.0
012
6.84
3.83
5.16
1.33
0.80
96.
360.
795.
0730
.18
1.06
3.04
0.41
2.57
0.40
0.71
23.5
450
.53
6.38
111.
0025
.47
152.
784.
685.
721.
440.
911
5.55
0.90
6.08
34.5
91.
223.
430.
483.
090.
461.
2820
.62
42.1
65.
557.
1022
.70
203.
096.
686.
591.
731.
133
10.5
62.
1315
.22
84.2
53.
288.
881.
196.
880.
99
APP
END
IX 1
: (C
) Nip
issi
ng G
abbr
o - G
eoch
emic
al D
ata
Sample JB97-65 JB97-78B JB97-48 JB97-49 JB98-207 JB98-224 JB98-239B JB98-239CTownship Wells Waters Wells Wells Kelly Janes Kelly Kelly
Field Name A A CM CM CM CM CM CMCIPW Name - - G G G G G GNormatives Q-H Q-H-C Q-H Q-H Q-H Q-H Q-H Q-HNorm Class so so so so so so so so
Norm Mineralsquartz 36.99 27.22 2.60 2.75 1.45 1.49 1.27 2.06
plagioclase 59.38 56.07 44.09 45.54 45.74 46.11 45.41 45.68orthoclase 0.65 4.37 5.91 6.50 3.43 1.54 6.32 3.60Nephelinecorundum 1.31diopside 0.32 19.77 15.83 23.38 20.13 19.58 20.33
hypersthene 1.11 4.44 22.79 24.19 22.61 26.29 24.11 24.93olivineilmenite 0.27 1.37 1.73 1.75 1.10 1.60 1.01 1.01
magnetite 0.22 0.62 2.58 2.73 2.09 2.61 2.04 2.20apatite 0.05 0.23 0.07 0.07 0.12 0.14 0.07 0.12zircon 0.01 0.01 0.01 0.01
chromite 0.01pyrite 0.28 1.27 0.13 0.17 0.11 0.13 0.19 0.08calcite 0.73 2.69 0.36 0.50
Na2CO3 0.40*Total: 100.01 99.99 100.03 100.03 100.04 100.05 100.01 100.02
*normalized to 100%; CIPW rock names based on weight % normative mineralsA = aplite; CM=chilled margin; G=gabbro; LG=leucogabbro; OPXG=orthopyroxene gabbro; MG=melagabbro; mtG=mt-bearing gabbroGG=Granophyric Gabbro; vtG=vari-textured Gabbro; qtzG=quartz GabbroOGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite;OLGN=olivine leucogabbronorite; LG=leucogabbro; LGN=leucogabbronoriteNormatives: Q=quartz; N=nepheline; H=hypersthene; O=olivine; C=corundumNorm Class: su=silica-undersaturated(alkali basalt); ss=silica-saturated(olivine tholeiites); so=silica-oversaturated (quartz tholeiites);
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB98-240 JB97-4B JB97-18 JB97-20 JB97-24 JB97-25 JB97-26 JB97-27 JB97-28Kelly Waters Kelly Kelly Clement Clement Clement Clement ClementCM G G G G G G G GG G G G G G G G G
Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso so so so so so so so so
1.40 1.13 3.40 3.16 2.25 2.65 2.49 2.62 3.1846.11 39.93 44.16 46.97 49.08 50.56 50.37 46.28 46.004.55 2.84 3.60 2.30 3.66 3.13 2.72 2.72 2.95
18.72 25.45 22.25 22.11 18.55 19.51 19.48 22.48 22.0225.64 27.25 23.13 22.20 22.18 20.36 21.01 21.83 21.47
1.18 0.91 1.01 0.99 1.27 1.18 1.22 1.12 1.422.22 1.99 2.03 1.90 2.35 2.09 2.20 2.16 2.380.12 0.05 0.05 0.09 0.07 0.09 0.07 0.090.01
0.11 0.04 0.13 0.04 0.04 0.11 0.15 0.13 0.150.50 0.27 0.30 0.52 0.39 0.30 0.61 0.34
100.06 100.04 100.03 100.02 99.99 100.05 100.03 100.02 100.00
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-29 JB97-30 JB97-31 JB97-32 JB97-34 JB97-36 JB97-40A JB97-40B JB97-41AClement Clement Clement Clement Foster Foster Janes Janes Janes
G G G G G G G G GG G G OLGN G G G G G
Q-H Q-H Q-H N-O Q-H Q-H Q-H Q-H Q-Hso so so su so so so so so
3.20 3.03 19.50 4.06 2.02 3.79 2.74 3.8950.14 49.26 30.12 54.78 45.58 51.39 44.81 41.17 47.203.19 4.02 7.62 6.91 4.79 6.09 2.78 2.54 2.01
1.01
18.50 19.06 17.56 8.00 16.60 8.88 18.16 18.17 9.5720.90 20.62 18.78 24.41 26.25 26.70 29.05 32.04
19.741.31 1.29 2.75 4.86 1.06 0.80 0.95 0.99 0.822.26 2.13 3.26 3.06 2.29 1.88 2.23 2.71 2.230.09 0.09 0.21 1.25 0.07 0.05 0.07 0.07 0.05
0.08 0.15 0.13 0.15 0.19 0.06 0.19 2.10 0.250.36 0.36 0.11 0.27 0.96 2.59 0.36 0.55 1.98
100.03 100.01 100.04 100.03 100.01 100.01 100.04 100.09 100.04
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-41C JB97-42A JB97-54B JB97-55 JB97-56 JB97-57 JB97-58 JB97-62 JB97-67Janes Janes Wells Wells Wells Wells Wells Wells Janes
G G G G G G G G GG G G G G G G G G
Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso so so so so so so so so
2.73 4.10 0.73 1.96 2.45 3.28 3.30 2.48 0.1639.78 40.86 45.41 43.71 45.22 44.18 45.95 52.14 44.844.67 0.30 7.45 8.92 5.79 5.56 3.84 3.96 2.66
21.83 20.87 17.76 17.15 20.04 19.68 20.12 14.73 28.2227.29 30.01 22.74 23.57 22.01 22.36 21.72 22.55 21.37
0.82 0.72 2.20 1.69 1.56 1.71 1.80 1.39 0.782.10 2.31 3.06 2.58 2.46 2.65 2.62 2.44 1.830.05 0.05 0.12 0.07 0.02 0.07 0.07 0.14 0.09
0.03 0.010.25 0.25 0.19 0.17 0.15 0.17 0.17 0.08 0.060.50 0.57 0.36 0.20 0.32 0.36 0.41 0.09
100.02 100.04 100.02 100.02 100.02 100.02 100.00 100.03 100.02
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-70C JB97-70D JB97-75 JB97-76A JB97-77A JB97-77B JB97-78A JB97-84DLouise Louise Waters Waters Waters Waters Waters Louise
G G G G G G G GG G LG G LGN GN OGN G
Q-H Q-H Q-H Q-H H-O H-O H-O-C Q-Hso so so so ss ss ss so
0.81 1.76 13.87 0.25 2.3937.52 38.87 40.18 52.86 54.56 49.76 6.85 41.152.30 2.42 8.86 4.73 5.44 2.90 36.88 3.43
6.2725.58 26.14 8.72 14.54 16.38 18.36 23.1630.18 27.38 17.22 24.05 10.40 18.23 37.55 26.83
7.83 3.53 6.280.76 0.80 6.82 1.42 1.61 1.98 1.54 0.872.06 1.90 2.99 1.68 2.39 2.87 3.48 1.840.07 0.07 0.56 0.14 0.07 0.12 0.05 0.12
0.07 0.07 0.01 0.10 0.100.21 0.15 0.06 0.32 0.40 1.82 0.38 0.080.52 0.52 0.73 0.93 0.45 0.73 0.11
100.08 100.08 100.02 100.09 100.01 100.02 100.01 100.08
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-87A JB97-87B JB97-87J JB97-87K JB97-93 JB97-99 JB97-103E JB97-106AJanes Janes Janes Janes Porter Scadding Kelly Janes
G G G G G G G GG G G G OLGN GN G G
Q-H Q-H Q-H Q-H H-O-C H-O Q-H Q-Hso so so so ss ss so so
5.20 3.12 3.24 5.39 1.65 3.3942.31 42.50 43.24 43.73 45.75 49.27 45.02 45.263.43 4.37 2.72 2.66 24.47 8.16 2.54 3.90
0.4921.25 22.53 22.71 22.16 11.93 23.64 19.2724.45 23.86 23.35 22.85 11.36 21.31 23.66 24.93
12.52 4.101.03 1.03 0.93 0.91 2.13 1.94 1.08 0.952.13 2.20 2.17 1.94 2.46 2.94 2.20 2.040.16 0.14 0.14 0.16 0.25 0.25 0.19 0.140.01 0.01 0.01 0.01 0.01 0.010.01 0.01 0.03 0.03 0.010.06 0.28 1.61 0.21 0.34 0.13 0.02 0.15
0.23
100.04 100.05 100.14 100.05 100.01 100.04 100.01 100.04
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-106C JB98-114 JB98-118 JB98-148 JB98-149 JB98-150 JB98-151C JB98-174Janes Waters Wells Lorne Lorne Lorne Lorne Curtin
G G G G G G G GG GN G LGN GN LG GN GN
Q-H H-O Q-H H-O H-O Q-H H-O H-Oso ss so ss ss so ss ss
1.06 0.24 0.8046.83 34.75 50.94 19.87 24.91 26.91 32.00 54.023.84 1.77 7.15 0.83 0.83 2.25 2.66 1.24
20.46 30.01 13.77 34.97 30.14 24.26 24.98 25.1824.24 28.48 23.63 35.28 34.62 42.78 34.15 7.05
2.48 6.41 6.88 3.17 8.631.14 0.68 1.61 0.51 0.53 0.80 0.87 1.082.19 1.84 2.38 2.12 2.07 2.19 2.13 2.090.16 0.21 0.05 0.05 0.05 0.07 0.120.01 0.01 0.01
0.08 0.02 0.06 0.02 0.02 0.02 0.02 0.61
100.01 100.03 100.00 100.06 100.05 100.06 100.05 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB98-175 JB98-177 JB98-178 JB98-179 JB98-180 JB98-181 JB98-183 JB98-184Curtin Curtin Curtin Curtin Curtin Curtin Curtin Curtin
G G G G G G G GG G G G G G GN GN
Q-H Q-H Q-H Q-H Q-H Q-H H-O H-Oso so so so so so ss ss
0.14 2.23 0.65 2.74 1.37 2.5447.44 50.89 45.48 38.92 42.02 47.89 41.25 46.096.86 5.26 4.25 6.26 4.96 5.32 4.67 4.79
18.58 13.23 15.64 19.69 20.70 18.34 24.84 27.0324.17 24.93 30.47 29.17 27.89 22.77 20.88 12.36
5.18 7.080.84 1.22 1.04 0.99 0.87 0.95 0.80 0.851.86 2.13 2.36 2.07 2.00 1.96 1.93 1.680.07 0.09 0.05 0.02 0.05 0.07 0.02 0.07
0.01 0.01 0.01 0.01
0.08 0.04 0.06 0.15 0.17 0.17 0.51 0.08
100.04 100.03 100.01 100.02 100.03 100.02 100.08 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB98-194 JB98-195 JB98-196 JB98-198 JB98-199 JB98-200 JB98-201 JB98-202Kelly Kelly Kelly Kelly Kelly Kelly Kelly Kelly
G G G G G G G GG G G G G GN G G
Q-H Q-H Q-H Q-H Q-H H-O Q-H Q-Hso so so so so ss so so
1.81 2.40 0.07 1.80 2.40 1.40 3.4046.76 46.78 48.80 41.16 44.51 42.76 43.36 43.013.49 3.13 3.01 3.66 3.07 2.54 3.01 4.14
21.88 21.75 22.55 24.86 22.27 26.92 24.06 22.3922.68 22.49 22.80 25.03 24.50 22.66 25.32 23.69
2.111.12 1.10 0.84 1.04 1.01 0.84 0.87 1.102.07 2.17 1.83 2.19 2.13 2.07 1.87 2.000.09 0.07 0.07 0.07 0.12 0.05 0.07 0.120.01 0.01 0.01 0.01 0.01
0.11 0.13 0.06 0.19 0.02 0.08 0.08 0.17
100.02 100.03 100.03 100.01 100.04 100.03 100.04 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB98-203 JB98-205 JB98-206 JB98-209C JB98-210A JB98-212B JB98-228 JB98-229Kelly Kelly Kelly Louise Louise Louise Curtin Curtin
G G G G G G G GG G G G G GN GN GN
Q-H Q-H Q-H Q-H Q-H H-O H-O H-Oso so so so so ss ss ss
0.52 0.03 1.43 25.40 1.5744.23 44.00 45.23 31.06 46.21 44.81 44.01 42.233.84 1.83 3.31 0.35 5.97 1.77 3.55 2.36
23.51 28.95 23.43 8.79 19.48 23.97 29.63 27.2424.98 22.77 23.81 32.67 23.38 22.28 15.08 23.43
4.62 5.42 2.190.89 0.68 0.87 0.40 1.16 0.57 0.72 0.681.81 1.67 1.81 1.17 1.91 1.70 1.59 1.770.12 0.05 0.07 0.07 0.09 0.05 0.02 0.07
0.01 0.01 0.01
0.13 0.04 0.08 0.06 0.25 0.28 0.02 0.04
100.03 100.02 100.05 99.98 100.03 100.05 100.04 100.01
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB98-230 JB98-231 JB98-239D JB98-239E JB98-239F RK-1 RK-2 RK-5 RK-7Curtin Curtin Kelly Kelly Kelly Waters Waters Waters Waters
G G G G G G G G GGN G GN G G G OGN LG GNH-O Q-H H-O Q-H Q-H Q-H H-O Q-H H-Oss so ss so so so ss so ss
2.42 1.11 3.36 17.14 5.3443.84 37.28 48.56 46.99 49.49 17.82 43.36 52.39 35.052.36 3.55 4.49 3.96 2.19 6.56 5.73 5.91 3.25
27.33 25.19 20.08 21.54 18.19 5.17 21.71 15.92 29.0520.39 28.63 23.51 23.24 23.56 48.67 16.75 15.15 27.113.59 0.08 9.59 2.340.68 0.78 1.03 1.04 1.03 0.66 0.55 2.32 0.841.71 2.04 1.96 1.94 2.09 2.25 1.83 2.35 1.960.02 0.05 0.12 0.09 0.07 0.07 0.07 0.37 0.09
0.01 0.01 0.01
0.11 0.11 0.19 0.11 0.04 1.59 0.02 0.08 0.020.14 0.43 0.18 0.32
100.03 100.05 100.03 100.03 100.03 100.07 100.04 100.01 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
RK-8 RK-9 RK-10 RK-11 RK-12 RK-13 RK-14 RK-15 RK-16 RK-17 RK-18Waters Waters Waters Waters Waters Waters Waters Waters Waters Waters Waters
G G G G G G G G G G GGN GN GN G G G GN LG GN GN LGNH-O H-O H-O Q-H Q-H Q-H H-O H-O H-O H-O H-Oss ss ss so so so ss ss ss ss ss
0.16 0.59 0.7634.52 21.92 20.71 20.15 20.36 53.23 56.21 59.48 46.17 45.67 19.713.01 1.24 1.24 1.12 1.24 3.07 2.90 3.25 3.37 2.72 1.24
28.78 40.05 38.72 34.50 37.96 18.22 20.26 17.44 26.91 25.65 35.6128.73 29.13 35.15 41.06 36.78 21.83 12.14 15.64 13.21 19.45 39.261.85 4.57 1.04 5.71 1.48 8.17 3.28 1.130.91 0.80 0.80 0.74 0.82 0.95 0.97 0.97 0.59 1.01 0.761.97 2.13 2.15 2.17 2.16 1.78 1.68 1.54 1.45 1.88 2.220.09 0.05 0.07 0.05 0.09 0.12 0.07 0.12 0.05 0.28 0.09
0.04 0.02 0.02 0.04 0.02 0.04 0.04 0.02 0.02 0.04 0.020.16 0.14 0.16 0.05 0.05 0.05 0.05 0.09 0.11 0.05
100.06 100.05 100.06 100.04 100.07 100.05 100.03 100.03 100.05 100.03 100.04
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
RK-19 JB97-50 JB97-54A JB97-63 JB98-122 JB97-14 JB97-15 JB97-16 JB97-43BWaters Wells Wells Wells Bridgland Kelly Kelly Kelly Janes
G GG GG GG GG OPXG OPXG OPXG OPXGLGN G LG G LG G G G GH-O Q-H Q-H-C Q-H Q-H Q-H Q-H Q-H Q-Hss so so so so so so so so
2.75 16.73 0.83 6.26 1.03 3.38 2.94 3.9060.02 40.51 34.46 49.64 45.28 47.85 43.61 43.90 45.043.37 12.47 0.41 9.63 10.93 2.66 2.72 2.72 2.90
4.4116.58 13.89 9.94 13.16 23.51 23.53 25.35 22.3014.42 23.69 23.54 23.89 17.92 21.50 23.04 21.47 22.012.980.93 2.68 0.93 2.11 3.02 0.89 1.06 1.03 1.041.58 3.25 3.23 2.87 2.96 1.77 2.15 2.03 1.960.09 0.12 0.25 0.25 0.37 0.07 0.07 0.05 0.07
0.030.01
0.02 0.23 1.99 0.17 0.11 0.11 0.08 0.17 0.080.05 0.45 12.79 0.68 0.64 0.39 0.36 0.73
1.24100.04 100.04 99.98 100.02 100.04 100.03 100.03 100.02 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-43D JB97-61 JB97-76B JB97-95 JB97-103B JB97-103D JB97-106B JB97-107Janes Wells Waters Janes Kelly Kelly Janes Janes
OPXG OPXG OPXG OPXG OPXG OPXG OPXG OPXGG OLGN GN G GN G G G
Q-H H-O H-O Q-H H-O Q-H Q-H Q-Hso ss ss so ss so so so
2.13 2.03 0.96 0.09 0.6346.01 50.50 52.78 42.16 39.14 42.00 47.38 43.962.07 8.92 2.72 3.31 2.07 3.72 2.54 3.19
24.28 9.26 19.72 25.54 31.97 26.75 21.64 28.3321.26 9.94 17.63 22.77 23.63 23.26 24.79 21.14
11.35 1.00 0.040.76 5.22 1.42 0.85 0.85 0.99 1.10 0.761.77 3.18 1.87 1.93 2.04 2.10 2.23 1.800.05 1.30 0.30 0.09 0.14 0.09 0.12 0.12
0.01 0.010.03 0.10
0.85 0.15 1.72 0.98 0.15 0.15 0.11 0.110.91 0.20 0.86 0.41
100.09 100.05 100.02 100.17 100.03 100.03 100.01 100.04
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-108 JB98-123 JB98-147 JB98-182 JB98-204 JB97-37 JB97-47 JB97-79BJanes Bridgland Lorne Curtin Kelly Foster Ermatinger Waters
OPXG OPXG OPXG OPXG OPXG LG LG LGG GN MGN GN G G G G
Q-H H-O H-O H-O Q-H Q-H Q-H Q-Hso ss ss ss so so so so
3.09 1.59 4.53 4.89 0.6342.08 50.08 16.11 41.08 45.02 46.71 46.98 42.952.95 1.89 0.24 4.20 2.19 4.08 2.95 3.13
25.45 25.24 37.81 25.54 25.58 18.81 18.57 23.5523.43 16.87 37.80 21.25 22.80 21.93 21.52 26.76
3.28 5.54 4.800.84 0.80 0.47 0.82 0.91 1.06 1.73 0.821.97 1.73 2.04 2.09 1.86 2.29 2.67 1.780.12 0.07 0.02 0.07 0.07 0.07 0.05 0.07
0.100.08 0.08 0.02 0.19 0.02 0.15 0.11 0.02
0.36 0.57 0.30
100.01 100.04 100.05 100.04 100.04 99.99 100.04 100.11
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-104 JB98-115 JB97-71 JB97-80A JB98-197 JB98-124 JB98-146 JB97-19AJanes Janes Louise Louise Kelly Kirkwood Lorne KellyLG LG MG MG mtG qtzG qtzG qtzGG G G G G G GN G
Q-H Q-H Q-H Q-H Q-H Q-H H-O Q-Hso so so so so so ss so
4.00 1.73 0.13 0.17 5.77 2.07 2.6439.26 43.24 44.78 43.19 45.34 46.49 47.30 43.041.95 3.31 4.14 4.43 4.61 5.02 1.89 1.71
24.30 21.15 22.22 25.65 18.77 21.76 23.61 23.2027.71 25.77 25.50 23.41 21.13 21.32 23.85 26.28
0.620.63 0.89 0.53 0.78 1.56 1.10 0.91 0.821.96 2.28 1.70 1.75 2.52 2.03 1.74 1.930.09 0.07 0.05 0.07 0.19 0.12 0.05 0.02
0.01 0.01 0.01 0.010.07 0.10
0.13 1.70 0.11 0.08 0.13 0.11 0.04 0.080.84 0.45 0.32
100.03 100.15 100.07 100.08 100.03 100.03 100.02 100.04
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-19B JB97-38 JB97-45 JB97-51 JB97-52 JB97-53 JB97-59 JB97-60 JB97-64Kelly Foster Moncrieff Wells Wells Wells Wells Wells WellsvtG vtG vtG vtG vtG vtG vtG vtG vtGG GN G LG G G G G LG
Q-H H-O Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso ss so so so so so so so
2.30 5.37 4.23 1.31 3.09 5.35 5.33 5.3444.55 51.52 44.91 49.14 45.15 42.66 43.26 43.22 44.645.02 7.68 5.08 6.26 10.81 11.05 6.56 6.32 10.05
23.97 15.48 13.02 7.06 4.84 14.21 16.91 17.43 13.8720.87 18.10 23.33 24.53 30.31 23.15 21.59 21.59 18.28
3.440.89 1.01 3.82 3.97 2.77 2.15 2.49 2.41 3.861.71 1.91 3.78 3.84 3.74 2.93 3.18 3.10 3.230.05 0.07 0.21 0.21 0.12 0.12 0.12 0.12 0.35
0.010.15 0.06 0.30 0.34 0.28 0.21 0.23 0.21 0.170.50 0.73 0.20 0.41 0.71 0.45 0.34 0.30 0.23
100.01 100.00 100.02 99.99 100.04 100.02 100.03 100.03 100.03
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-66 JB97-98 JB97-100 JB97-105 JB98-119 JB98-120 JB98-121A JB97-41BWells Scadding Scadding Janes Wells Wells Wells JanesvtG vtG vtG vtG vtG vtG vtG GLG G G G G G LG GQ-H Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso so so so so so so so
4.05 0.96 1.60 0.88 6.98 6.08 9.27 1.7147.98 45.33 41.56 49.96 46.40 44.86 44.87 38.857.80 4.67 5.20 1.95 6.97 10.22 10.28 4.49
13.30 20.70 22.76 24.76 13.66 14.34 3.49 19.9118.67 24.75 25.28 20.04 19.08 18.69 25.48 28.71
4.41 1.06 1.14 0.66 3.38 2.66 3.02 0.763.26 2.26 2.20 1.62 3.03 2.80 3.04 2.610.30 0.14 0.19 0.09 0.37 0.30 0.44 0.02
0.01 0.03 0.03 0.030.010.11 0.15 0.08 0.04 0.13 0.04 0.11 2.570.14 0.48
100.03 100.02 100.02 100.00 100.03 100.02 100.03 100.11
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-42B JB97-43A JB97-43C JB97-109 JB97-87C JB97-87D JB97-87E JB97-87FJanes Janes Janes Janes Janes Janes Janes Janes
G OPXG OPXG OPXG G G G GG G G LG G G G G
Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso so so so so so so so
1.98 3.79 1.29 2.37 8.50 2.61 7.79 7.1039.69 39.41 40.78 49.27 40.70 40.99 38.63 41.034.14 3.49 1.00 0.71 1.12 4.08 3.07 1.89
17.55 18.29 21.74 3.15 13.83 18.24 13.38 15.8328.80 23.68 25.55 28.39 28.40 23.49 28.69 25.47
0.72 0.89 0.85 1.14 0.89 0.93 0.99 0.952.81 3.00 3.02 3.71 2.77 2.94 2.86 2.770.02 0.05 0.05 0.19 0.16 0.12 0.12 0.14
0.01 0.010.03 0.01 0.01 0.03
4.07 7.76 5.98 12.38 3.99 7.21 4.90 5.280.39 0.32 0.27
100.17 100.68 100.53 101.31 100.40 100.62 100.45 100.49
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
JB97-87G JB97-87H JB97-87I 44731 44737 44744 44769 44792 44799 44805Janes Janes Janes Janes Janes Janes Janes Janes Janes Janes
G G G vtG vtG OPXG OPXG OPXG OPXG OPXGG G G GN G GN GN GN G G
Q-H Q-H Q-H H-O Q-H H-O H-O H-O Q-H Q-Hso so so ss so ss ss ss so so
8.98 5.47 4.36 0.8 0.7 1.0838.43 41.50 41.55 48.6 44.96 44.86 48.3 43.16 44.37 45.173.07 2.66 3.19 4.25 2.3 2.36 3.84 2.54 2.6 1.89
15.12 18.92 20.64 26.73 29.37 29.21 25.56 27.02 24.64 23.4527.07 24.33 24.69 10.94 20.19 19.27 11.83 21.5 24.11 22.71
7.06 1.58 7.03 1.370.87 0.82 0.85 0.76 0.7 0.76 0.68 0.8 0.8 0.782.58 2.48 2.32 1.57 1.54 1.7 1.65 1.91 1.84 2.10.16 0.14 0.12 0.05 0.05 0.09 0.07 0.07 0.07 0.07
0.01 0.03 0.013.99 4.05 2.48 0.06 0.11 0.19 1.1 1.76 0.98 2.99
100.28 100.40 100.21 100.02 100.02 100.02 100.06 100.13 100.11 100.24
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
44812 44685 44692 44700 44705 44708 44711 44713 44714 44716 44718Janes Janes Janes Janes Janes Janes Janes Janes Janes Janes Janes
OPXG OPXG OPXG OPXG OPXG OPXG OPXG OPXG OPXG OPXG OPXGG G G G G G G G G G G
Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H Q-Hso so so so so so so so so so so
2.46 2.04 4.33 1.37 3.66 3.25 3.15 4.8 4.4 3.43 1.6144.85 41.91 40.64 46.43 44.21 44.74 42.76 41.19 40.54 44.49 45.281.89 2.54 3.19 1.89 2.19 2.01 2.01 2.01 2.13 2.13 2.07
20.87 20.06 17.52 20.51 20.2 20.54 19.12 17.53 18.43 16.92 18.5124.08 23.4 25.17 23.23 22.57 22.46 24.38 25.79 25.34 26.14 25.38
0.84 0.78 0.8 0.87 0.84 0.84 0.74 0.74 0.78 0.93 0.932.15 2.67 2.6 2.28 2.35 2.33 2.61 2.7 2.78 2.32 2.420.07 0.02 0.07 0.05 0.05 0.07 0.09 0.09 0.05 0.07 0.07
2.99 7.15 6.11 3.71 4.3 4.09 5.73 5.7 6.15 3.94 4.09
100.20 100.57 100.43 100.34 100.37 100.33 100.59 100.55 100.60 100.37 100.36
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
SampleTownship
Field NameCIPW NameNormativesNorm Class
Norm Mineralsquartz
plagioclaseorthoclaseNephelinecorundumdiopside
hyperstheneolivineilmenite
magnetiteapatitezircon
chromitepyritecalcite
Na2CO3
*Total:
44720 44722 44725 44758Janes Janes Janes Janes
OPXG G G GG G OLGN G
Q-H Q-H H-O Q-Hso so ss so
0.81 2.64 2.2245.5 46.48 47.84 45.32.25 2.66 5.91 3.19
22.01 20.96 8.44 21.8325.12 24.27 6.96 24.34
27.10.95 0.91 0.99 0.972.13 1.9 2.17 1.940.07 0.07 0.09 0.09
1.31 0.13 0.51 0.13
100.15 100.02 100.01 100.01
APPENDIX 1: (D) Nipissing Gabbro CIPW Normatives
Sample No. LLD Method1 SZM01 SZM02 SZM03 SZM04 SZM05 CZM01 CZM02Field Name gab gab gab Lgab gab Lgab Lgab
CIPW3 OGN GN GN OLGN GN Lgab GNTexture mg mg mg mg-cg mg cg cgFeature2 massive massive massive massive massive massive b-qtz; biot
V-S 0 0 3 2 1 2 <1Type2 M M M M M M M
Strat. Unit BX BX BX BX BX BX BXSiO2 0.01 1 49.67 50.27 50.05 48.74 50.42 51.20 51.32TiO2 0.01 1 0.27 0.21 0.17 0.15 0.19 0.55 0.46Al2O3 0.01 1 16.65 17.24 17.08 23.47 16.90 19.06 16.12
Fe2O3* 0.01 1 10.52 9.29 9.73 7.70 9.61 8.41 10.51MnO 0.01 1 0.18 0.16 0.17 0.10 0.17 0.15 0.19MgO 0.01 1 8.53 8.44 8.33 3.64 8.55 5.33 7.60CaO 0.01 1 10.23 10.37 9.96 10.15 10.69 11.10 9.69Na2O 0.01 1 2.68 2.48 2.44 3.15 2.24 2.61 2.45K2O 0.01 1 0.33 0.34 0.52 0.92 0.24 0.83 1.02P2O5 0.01 1 0.01 0.01 0.02 0.02 0.02 0.03 0.04CO2 0.03 3 0.12 0.09 0.03 0.04 0.02 0.08 0.03
S 0.01 3 0.03 0.09 0.36 0.77 0.08 0.05 0.03LOI 0.05 2 1.27 1.35 1.46 1.47 1.17 1.14 0.80
Total: 100.34 100.17 99.91 99.51 100.22 100.42 100.20Mg# 65 68 67 52 67 60 63Cs 0.007 5 0.227 0.238 0.322 0.729 0.212 0.785 0.993Rb 0.050 5 4.140 6.080 13.210 16.960 3.770 22.410 30.440Ba 1.000 5 76 84 74 141 57 268 336Th 0.060 5 0.080 0.080 0.170 0.410 0.060 1.310 0.840U 0.007 5 0.035 0.027 0.042 0.170 0.020 0.429 0.240
Nb 0.200 5 0.200 0.200 0.400 0.500 0.100 1.400 1.200Ta 0.170 5 0.090 0.180 0.090 0.180 0.090 0.220 0.220La 0.020 5 2.420 1.970 2.010 2.830 1.680 6.610 5.730Ce 0.070 5 5.720 4.300 4.140 5.820 3.650 13.940 12.050Pr 0.006 5 0.786 0.581 0.570 0.746 0.542 1.703 1.595Sr 0.500 5 360 342 365 510 284 648 406Nd 0.030 5 3.850 2.600 2.500 2.910 2.270 6.660 6.380Zr 4.000 5 9.900 9.300 9.100 15.300 9.200 38.800 28.000Hf 0.100 5 0.300 0.300 0.300 0.400 0.300 1.100 0.800Sm 0.010 5 1.040 0.770 0.630 0.730 0.660 1.600 1.620Eu 0.005 5 0.565 0.398 0.401 0.506 0.393 0.717 0.774Ti 10.000 5 1223 1020 743 679 879 2749 2081Gd 0.009 5 1.206 0.761 0.821 0.789 0.911 1.593 1.931Tb 0.003 5 0.213 0.140 0.151 0.108 0.157 0.302 0.297Dy 0.008 5 1.244 1.012 0.909 0.711 0.921 1.813 1.875Y 0.020 5 7.210 6.110 4.240 3.930 5.170 9.070 9.940Ho 0.003 5 0.297 0.220 0.206 0.172 0.232 0.366 0.420Er 0.008 5 0.872 0.668 0.602 0.497 0.641 1.042 1.304Tm 0.003 5 0.137 0.097 0.083 0.078 0.106 0.162 0.172Yb 0.010 5 0.900 0.760 0.590 0.530 0.700 1.040 1.160Lu 0.003 5 0.155 0.102 0.088 0.073 0.103 0.153 0.198
∑REE 19.41 14.38 13.70 16.50 12.97 37.70 35.51Se 8 7 128 773 2476 6011 669 163 112Ni 3 4 189 253 367 632 261 107 139Ir 0.04 6 0.33 3.79 8.18 33.10 4.79 1.20 0.20
Ru 0.13 6 0.21 1.80 2.59 20.20 2.29 1.90 0.30
APPENDIX 1: (E) River Valley - Matrix/Fragment
Sample No. LLD Method1 SZM01 SZM02 SZM03 SZM04 SZM05 CZM01 CZM02Field Name gab gab gab Lgab gab Lgab Lgab
CIPW3 OGN GN GN OLGN GN Lgab GNTexture mg mg mg mg-cg mg cg cgFeature2 massive massive massive massive massive massive b-qtz; biot
V-S 0 0 3 2 1 2 <1Type2 M M M M M M M
Strat. Unit BX BX BX BX BX BX BXRh 0.08 6 1.15 18.90 40.60 156.00 25.30 5.49 0.40Pt 0.14 6 13.40 171.00 360.00 1637.00 200.00 61.30 8.98Pd 0.11 6 18.40 623.00 1261.00 7164.00 797.00 125.00 12.50Au 0.71 6 7.73 34.70 88.70 192.00 53.20 19.50 7.38Cu 3 4 175.0 614.0 1901.0 2586.0 673.0 319.0 219.0
Pd+Pt 32 794 1621 8801 997 186 21Pd/Ir 55.76 164.38 154.16 216.44 166.39 104.17 62.50Cu/Ni 0.9 2.4 5.2 4.1 2.6 3.0 1.6S/Se 2344 1164 1454 1281 1196 3067 2679Pd/Pt 1.4 3.6 3.5 4.4 4.0 2.0 1.4
Notes: Major Element Oxides, S, CO2, and LOI are in wt. percent; trace element contents are in ppm; Cu-Ni contents are in ppm; PGE and Se contents are in ppbLLD=lower limit of detection; "-" = not detected/determined1Method: 1=WD-XRF, 2=Lebo thermogravimetry, 3=Leco infrared combustion, 4=DCP, 5=ICP-MS, 6=NiS/ICP-MS, 7=AAS-hydride,8=Fire Assay/DCP2Sample Type/Features: M=matrix; F=fragment; b-qtz=blue quartz; biot=biotite; hem=hematiteRock Type: Mgab=melagabbro, Lgab=leucogabbro;gab=gabbro; V-S=visible sulphide3CIPW Name: OGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite; OLGN=olivine leucogabbronorite; LG=leucogabbro
APPENDIX 1: (E) River Valley - Matrix/Fragment
Sample No.Field Name
CIPW3
TextureFeature2
V-SType2
Strat. UnitSiO2
TiO2
Al2O3
Fe2O3*MnOMgOCaONa2OK2OP2O5
CO2
SLOI
Total:Mg#CsRbBaThU
NbTaLaCePrSrNdZrHfSmEuTiGdTbDyYHoErTmYbLu
∑REESeNiIr
Ru
CZM03 SZF01 SZF02 SZF03 SZF04 SZF05 CZF01 CZF02 CZF03gab Mgab Mgab Mgab Mgab gab gab gab gabGN MGN MGN OMGN MGN MGN GN GN MGN
mg-cg fg fg fg-mg mg fg-mg fg-mg fg fgb-qtz; biot massive massive massive biot massive massive biot-hem massive
<1 0 0 2 3 2 1 1 2M F F F F F F F FBX BX BX BX BX BX BX BX BX
51.19 48.68 48.77 46.05 50.79 48.39 47.31 47.10 48.260.43 0.45 0.46 0.24 0.84 0.27 0.27 0.37 0.38
15.89 5.96 6.92 7.51 5.74 8.47 11.58 9.34 11.0210.50 14.74 13.81 15.44 15.86 14.52 14.61 15.86 15.200.19 0.26 0.26 0.28 0.25 0.25 0.24 0.26 0.247.88 14.73 14.56 16.09 12.94 13.85 12.62 13.33 12.009.32 12.04 12.08 10.33 9.64 10.46 7.55 8.60 7.442.26 0.57 0.72 0.45 0.41 0.66 0.35 0.57 0.711.05 0.12 0.22 0.08 0.86 0.15 0.66 1.09 1.220.05 0.07 0.02 0.01 0.08 0.01 0.02 0.03 0.030.04 0.10 0.15 0.09 0.05 0.05 0.06 0.02 0.040.13 0.19 0.02 0.23 0.97 0.38 0.15 0.03 0.141.13 1.11 1.21 2.43 1.23 1.80 3.04 1.98 2.22
99.89 98.72 99.04 98.91 98.63 98.83 98.24 98.53 98.7264 70 71 71 66 69 67 66 65
1.052 0.122 0.202 0.151 1.645 0.153 0.806 1.533 1.70635.050 0.920 4.470 1.080 36.640 1.350 20.710 36.900 43.360
397 90 64 20 352 99 251 356 4611.160 1.050 0.490 0.130 3.070 0.100 0.480 0.480 0.6300.256 0.348 0.137 0.037 0.820 0.028 0.115 0.157 0.1501.300 1.100 0.800 0.300 3.500 0.100 0.600 0.700 0.7000.220 0.250 0.210 0.090 0.400 0.090 0.090 0.190 0.2206.400 2.680 2.100 0.610 10.170 1.340 3.170 2.660 4.53013.340 8.260 5.290 1.510 24.260 3.380 6.480 5.920 9.5901.706 1.286 0.807 0.269 3.110 0.492 0.831 0.789 1.259393 12 34 7 11 27 117 11 70
7.040 6.440 3.610 1.430 13.160 2.580 3.480 3.450 5.22045.200 46.100 23.200 11.100 69.600 9.900 16.200 19.600 21.0001.200 1.500 0.800 0.400 2.100 0.400 0.500 0.700 0.6001.620 1.900 1.240 0.680 3.120 0.760 0.820 0.930 1.2400.901 0.411 0.461 0.228 0.516 0.317 0.339 0.356 0.6142029 1996 2192 1074 3813 1248 1243 1732 17571.836 2.502 1.784 1.019 3.249 1.157 1.164 1.318 1.5760.306 0.394 0.361 0.178 0.501 0.214 0.182 0.236 0.2741.894 2.291 2.232 1.222 3.226 1.227 1.146 1.461 1.75310.450 10.760 11.410 5.720 17.310 7.020 6.670 7.650 8.7600.447 0.450 0.474 0.261 0.764 0.295 0.240 0.333 0.3721.254 1.359 1.530 0.762 2.115 0.847 0.839 0.974 1.1230.211 0.213 0.216 0.100 0.318 0.153 0.116 0.143 0.1651.350 1.240 1.380 0.710 2.120 0.930 0.820 1.040 0.9400.218 0.179 0.211 0.115 0.319 0.142 0.135 0.157 0.17238.52 29.61 21.70 9.09 66.95 13.83 19.76 19.77 28.83466 1614 231 1260 5981 2389 1589 77 631164 399 327 496 427 605 428 256 3080.53 0.08 3.29 0.13 14.60 21.60 0.30 0.25 0.220.59 0.33 1.60 0.26 6.98 10.10 0.44 0.30 0.38
APPENDIX 1: (E) River Valley - Matrix/Fragment
Sample No.Field Name
CIPW3
TextureFeature2
V-SType2
Strat. UnitRhPtPdAuCu
Pd+PtPd/IrCu/NiS/SePd/Pt
CZM03 SZF01 SZF02 SZF03 SZF04 SZF05 CZF01 CZF02 CZF03gab Mgab Mgab Mgab Mgab gab gab gab gabGN MGN MGN OMGN MGN MGN GN GN MGN
mg-cg fg fg fg-mg mg fg-mg fg-mg fg fgb-qtz; biot massive massive massive biot massive massive biot-hem massive
<1 0 0 2 3 2 1 1 2M F F F F F F F FBX BX BX BX BX BX BX BX BX2.21 0.10 16.60 0.28 75.10 103.00 0.46 0.39 0.33
20.70 1.44 210.00 4.31 683.00 847.00 8.16 7.20 4.6175.90 1.79 713.00 11.20 1899.00 3196.00 22.60 2.94 4.7528.90 7.91 22.40 23.10 143.00 164.00 24.60 8.72 17.90651.0 275.0 179.0 716.0 2008.0 2202.0 523.0 175.0 486.0
97 3 923 16 2582 4043 31 10 9143.21 22.38 216.72 86.15 130.07 147.96 75.33 11.76 21.59
4.0 0.7 0.5 1.4 4.7 3.6 1.2 0.7 1.62790 1177 866 1825 1622 1590 944 3896 22193.7 1.2 3.4 2.6 2.8 3.8 2.8 0.4 1.0
APPENDIX 1: (E) River Valley - Matrix/Fragment
Sample SZM01 SZF01 SZM02 SZF02 SZM03 SZF03 SZM04 SZF04Rock Type OGN MGN GN MGN GN OMGN OLGN MGN
Norm Mineralsquartz 5.25
plagioclase 56.06 18.82 56.93 21.77 55.86 23.10 75.19 15.17orthoclase 2.01 0.71 2.07 1.36 3.13 0.47 5.56 5.26diopside 14.66 37.99 13.34 36.69 12.54 27.40 2.55 29.95
hypersthene 13.50 34.72 19.41 30.56 19.76 31.46 3.33 37.02olivine 10.76 2.96 5.56 5.40 5.52 13.07 9.82
ilmenite 0.51 0.89 0.40 0.91 0.32 0.47 0.28 1.65magnetite 2.17 3.10 1.91 2.90 2.02 3.28 1.59 3.32
apatite 0.02 0.16 0.05 0.05 0.05 0.05 0.19zircon 0.01 0.01
chromite 0.04 0.09 0.06 0.09 0.06 0.09 0.01 0.04pyrite 0.06 0.42 0.19 0.04 0.78 0.51 1.65 2.12calcite 0.27 0.23 0.20 0.34 0.07 0.20 0.09 0.11
*Total: 100.06 100.10 100.07 100.11 100.11 100.10 100.12 100.09Sample SZM05 SZF05 CZM01 CZF01 CZM02 CZF02 CZM03 CZF03
Rock Type GN MGN LG GN GN GN GN MGNNorm Minerals
quartz 0.23 1.40plagioclase 55.28 26.28 60.76 32.96 51.49 25.78 50.25 30.67orthoclase 1.42 0.95 4.96 4.14 6.09 6.74 6.32 7.56diopside 14.60 26.91 13.98 7.75 14.80 19.52 13.15 11.38
hypersthene 23.44 40.20 16.97 49.56 21.62 35.18 26.49 45.48olivine 2.73 1.16 2.76 8.53 0.33 0.45
ilmenite 0.36 0.53 1.06 0.55 0.89 0.74 0.84 0.76magnetite 1.99 3.06 1.73 3.15 2.16 3.38 2.17 3.23
apatite 0.05 0.07 0.05 0.09 0.07 0.12 0.07zircon 0.01 0.01
chromite 0.04 0.09 0.03 0.09 0.04 0.09 0.06 0.09pyrite 0.17 0.85 0.11 0.34 0.06 0.06 0.28 0.32calcite 0.11 0.18 0.14 0.07 0.09 0.09
*Total: 100.08 100.14 100.09 100.13 100.07 100.09 100.11 100.10*normalized to 100%; "SZ" = South Zone, "CZ" = Central Zone"M" = matrix, "F" = fragment; rock names based on weight % normative mineralsOGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite;OLGN=olivine leucogabbronorite; LG=leucogabbro
APPENDIX 1: (F) River Valley Intrusion - CIPW Matrix/Fragment
Sample 22692 22696 29601 29607 29612 29618 29622 29635 29645 29654Rock Type OGN OGN OGN OGN GN OGN OGN OGN OLGN LGN
Unit LU LU LU LU LU LU LU LU IBZ IBZNorm Minerals
quartzplagioclase 53.91 53.50 56.67 55.81 58.01 47.03 57.45 42.44 73.12 73.99orthoclase 3.78 3.60 3.60 3.31 4.14 3.13 3.90 4.85 5.20 5.26corundumdiopside 9.54 8.77 6.71 9.31 8.72 12.07 8.64 11.19 7.03 5.17
hypersthene 18.03 19.15 16.58 16.50 17.67 19.16 16.81 17.65 0.53 6.78olivine 10.91 11.35 12.58 11.41 7.90 14.53 9.50 18.85 11.70 6.68ilmenite 0.91 0.74 0.82 0.89 0.85 0.80 0.84 1.35 0.74 0.59
magnetite 2.49 2.52 2.52 2.42 2.23 3.00 2.38 3.29 1.41 1.23apatite 0.14 0.12 0.14 0.12 0.14 0.05 0.09 0.14 0.12 0.09zircon 0.01 0.01 0.01
chromitepyrite 0.13 0.06 0.13 0.08 0.15 0.11 0.19 0.17 0.06 0.04calcite 0.16 0.23 0.27 0.16 0.23 0.16 0.25 0.09 0.14 0.16
*Total: 100.01 100.04 100.02 100.02 100.04 100.04 100.05 100.03 100.05 99.99
Sample 29702 29707 29717 29721 29733 29744 29753 29756 29762Rock Type LGN GN GN LGN G OLGN OGN GN LGN
Unit BX BX BX BX BX BX BX BX FBXNorm Minerals
quartz 3.34plagioclase 65.97 55.10 51.10 62.23 32.83 62.15 54.09 48.91 59.01orthoclase 4.79 2.25 2.84 2.72 4.37 3.49 5.50 5.97 8.16corundum 0.18diopside 5.41 13.34 10.97 9.21 13.02 9.45 5.85 15.38
hypersthene 12.85 21.52 30.54 18.46 41.80 10.37 6.62 24.64 21.19olivine 7.24 3.59 1.63 5.19 12.14 23.95 1.76 6.81ilmenite 0.27 0.36 0.32 0.30 0.55 0.42 0.53 0.65 1.39
magnetite 1.81 2.09 2.16 1.65 2.93 1.78 2.44 2.31 2.16apatite 0.02 0.02 0.02 0.02 0.05 0.02 0.07 0.02 0.14zircon
chromitepyrite 1.70 1.70 0.38 0.11 1.04 0.02 0.76 0.32 0.93calcite 0.05 0.14 0.09 0.16 0.11 0.20 0.25 0.09 0.07
*Total: 100.11 100.11 100.05 100.05 100.04 100.04 100.06 100.05 100.04*normalized to 100%; rock names based on weight % normative mineralsOGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite;OLGN=olivine leucogabbronorite; LG=leucogabbro
APPENDIX 1: (F) River Valley Intrusion - CIPW RV00-22
Sample 29662 29670 29676 29683 29689 29696Rock Type LGN OLGN LGN LGN GN GN
Unit IBZ IBZ IBZ IBZ BX BXNorm Minerals
quartzplagioclase 65.43 66.27 64.30 69.73 52.45 39.35orthoclase 4.37 2.54 2.95 4.79 1.77 3.37corundumdiopside 8.75 5.28 13.44 8.19 16.09 14.53
hypersthene 11.42 10.53 10.15 11.08 18.65 35.24olivine 7.65 13.32 6.87 4.65 8.73 3.52ilmenite 0.49 0.21 0.28 0.27 0.25 0.46
magnetite 1.55 1.70 1.36 1.13 1.88 2.78apatite 0.07 0.02 0.02 0.02 0.02 0.02zircon
chromitepyrite 0.04 0.02 0.04 0.02 0.08 0.64calcite 0.25 0.14 0.59 0.14 0.09 0.16
*Total: 100.02 100.03 100.00 100.02 100.01 100.07
APPENDIX 1: (F) River Valley Intrusion - CIPW RV00-22
Sample From To Interval Tag No. Au(ppb) Pt(ppb) Pd(ppb) Ni(ppm) Cu(ppm) Strat1 0.00 1.00 1.00 22690 8 39 27 91 86.5 LU2 1.00 2.50 1.50 22691 14 33 27 102 77.4 LU3 2.50 4.00 1.50 22692 7 41 29 116 117 LU4 4.00 5.50 1.50 22693 8 48 29 112 112 LU5 5.50 7.00 1.50 22694 16 42 31 102 103 LU6 7.00 8.50 1.50 22695 7 25 23 108 95.5 LU7 8.50 10.00 1.50 22696 9 53 26 105 110 LU8 10.00 12.00 2.00 22697 5 14 10 105 96.3 LU9 12.00 14.00 2.00 22698 6 27 19 90 84.5 LU10 14.00 16.00 2.00 22699 10 29 22 88 99.5 LU11 16.00 18.00 2.00 22700 7 37 23 101 107 LU12 18.00 20.00 2.00 29601 8 30 22 79 77.5 LU13 20.00 22.00 2.00 29602 9 32 17 89 96.8 LU14 22.00 24.00 2.00 29603 7 20 17 79 94.2 LU15 24.00 26.00 2.00 29604 5 10 12 78 97.5 LU16 26.00 28.00 2.00 29605 9 45 29 79 83.1 LU17 28.00 30.00 2.00 29606 10 36 33 76 102 LU18 30.00 32.00 2.00 29607 7 36 29 87 93 LU19 32.00 34.00 2.00 29608 7 31 23 105 92.9 LU20 34.00 36.00 2.00 29609 9 29 31 90 95.9 LU21 36.00 38.00 2.00 29610 7 22 18 89 116 LU22 38.00 40.00 2.00 29611 7 23 19 77 94.6 LU23 40.00 42.00 2.00 29612 3 25 11 76 64.7 LU24 42.00 44.00 2.00 29613 5 24 13 81 116 LU25 44.00 46.00 2.00 29614 5 24 14 75 51.3 LU26 46.00 48.00 2.00 29615 6 16 12 72 81.6 LU27 48.00 49.35 1.35 29616 1 22 8 76 47 LU28 49.35 50.85 1.50 29617 3 0 0 23 21.7 LU29 50.85 52.00 1.15 29618 4 18 11 78 97.8 LU30 52.00 54.00 2.00 29619 3 28 16 90 101 LU31 54.00 56.00 2.00 29620 3 20 11 91 90.8 LU32 56.00 58.00 2.00 29621 3 28 13 103 87.9 LU33 58.00 60.00 2.00 29622 3 0 8 94 92 LU34 60.00 61.75 1.75 29623 13 56 27 138 21.1 LU35 61.75 62.60 0.85 29624 12 33 14 24 37.1 LU36 62.60 64.00 1.40 29625 10 36 17 109 67.3 LU37 64.00 66.10 2.10 29626 10 40 24 113 84.8 LU38 66.10 67.40 1.30 29627 9 49 27 172 78.4 LU39 67.40 68.85 1.45 29628 12 44 38 90 143 LU40 68.85 70.20 1.35 29629 13 31 30 113 108 LU41 70.20 72.20 2.00 29630 10 49 29 96 119 LU42 72.20 74.00 1.80 29631 10 38 23 107 132 LU43 74.00 75.18 1.18 29632 8 41 16 120 55.9 LU44 75.18 75.30 0.12 29633 10 59 17 279 9590 LU45 75.30 77.00 1.70 29634 10 27 26 112 118 LU46 77.00 79.00 2.00 29635 12 33 15 158 134 LU47 79.00 81.00 2.00 29636 9 19 12 179 82.7 LU48 81.00 81.40 0.40 29637 11 23 10 212 164 LU49 81.40 82.80 1.40 29638 7 15 10 136 99.2 LU50 82.80 85.00 2.20 29639 10 31 20 90 108 LU51 85.00 86.50 1.50 29640 11 44 33 104 145 LU52 86.50 88.00 1.50 29641 11 31 22 155 118 LU
APPENDIX 1: (G) River Valley Intrusion - Group-1 Data RV00-22
Sample From To Interval Tag No. Au(ppb) Pt(ppb) Pd(ppb) Ni(ppm) Cu(ppm) Strat53 88.00 89.50 1.50 29642 8 33 22 93 113 LU54 89.50 91.00 1.50 29643 9 24 20 57 33.4 IBZ55 91.00 92.50 1.50 29644 7 26 17 63 84.8 IBZ56 92.50 94.00 1.50 29645 12 208 581 44 40.5 IBZ57 94.00 95.50 1.50 29646 6 30 21 41 43.7 IBZ58 95.50 97.00 1.50 29647 4 23 12 30 96.9 IBZ59 97.00 98.50 1.50 29648 4 24 14 85 45.5 IBZ60 98.50 100.00 1.50 29649 5 25 18 77 45.9 IBZ61 100.00 102.00 2.00 29650 5 15 15 65 55 IBZ62 102.00 104.00 2.00 29651 12 28 17 78 125 IBZ63 104.00 106.00 2.00 29652 6 34 13 49 54 IBZ64 106.00 108.00 2.00 29653 11 24 13 50 86.8 IBZ65 108.00 110.00 2.00 29654 5 33 13 27 47.9 IBZ66 110.00 112.00 2.00 29655 6 24 11 63 40.4 IBZ67 112.00 114.00 2.00 29656 5 34 11 30 54.9 IBZ68 114.00 116.00 2.00 29657 3 31 19 31 46.6 IBZ69 116.00 118.00 2.00 29658 6 30 18 30 60.9 IBZ70 118.00 120.00 2.00 29659 4 32 17 34 34.2 IBZ71 120.00 122.30 2.30 29660 3 32 20 41 33.9 IBZ72 122.30 124.00 1.70 29661 9 129 222 61 59.1 IBZ73 124.00 126.00 2.00 29662 4 87 86 40 36 IBZ74 126.00 128.00 2.00 29663 9 72 59 28 145 IBZ75 128.00 130.00 2.00 29664 9 84 63 32 96.6 IBZ76 130.00 132.00 2.00 29665 9 68 56 29 121 IBZ77 132.00 134.00 2.00 29666 14 58 49 34 109 IBZ78 134.00 135.50 1.50 29667 7 83 90 18 41.1 IBZ79 135.50 136.55 1.05 29668 8 38 64 23 54.6 IBZ80 136.55 138.00 1.45 29669 3 53 62 63 33.7 IBZ81 138.00 140.00 2.00 29670 7 198 192 81 13.6 IBZ82 140.00 142.00 2.00 29671 6 170 257 60 29.6 IBZ83 142.00 144.00 2.00 29672 2 45 65 87 22.8 IBZ84 144.00 146.00 2.00 29673 6 110 131 69 27.1 IBZ85 146.00 148.00 2.00 29674 5 101 121 109 10.7 IBZ86 148.00 150.00 2.00 29675 16 70 66 27 73.6 IBZ87 150.00 152.00 2.00 29676 14 134 130 27 95.9 IBZ88 152.00 152.90 0.90 29677 10 118 105 30 53.3 IBZ89 152.90 154.00 1.10 29678 9 32 17 15 82.1 IBZ90 154.00 155.50 1.50 29679 38 125 109 32 57.3 IBZ91 155.50 157.00 1.50 29680 7 89 62 32 42.4 IBZ92 157.00 158.50 1.50 29681 27 287 520 26 116 IBZ93 158.50 160.00 1.50 29682 12 153 202 25 49.3 IBZ94 160.00 160.80 0.80 29683 34 206 331 19 48.9 IBZ95 160.80 161.80 1.00 29684 26 76 108 48 305 BX96 161.80 162.50 0.70 29685 52 304 600 62 335 BX97 162.50 163.00 0.50 29686 30 124 144 73 414 BX98 163.00 165.00 2.00 29687 37 156 273 28 62.1 BX99 165.00 166.65 1.65 29688 28 80 139 141 368 BX
100 166.65 167.50 0.85 29689 19 74 204 68 262 BX101 167.50 168.50 1.00 29690 23 93 122 55 243 BX102 168.50 170.15 1.65 29691 7 68 94 44 283 BX103 170.15 171.15 1.00 29692 36 141 289 34 274 BX104 171.15 172.00 0.85 29693 27 94 225 47 203 BX
APPENDIX 1: (G) River Valley Intrusion - Group-1 Data RV00-22
Sample From To Interval Tag No. Au(ppb) Pt(ppb) Pd(ppb) Ni(ppm) Cu(ppm) Strat105 172.00 173.00 1.00 29694 13 53 87 58 56.7 BX106 173.00 173.50 0.50 29695 45 166 391 123 553 BX107 173.50 175.00 1.50 29696 119 553 1173 156 1220 BX108 175.00 176.25 1.25 29697 76 359 818 132 735 BX109 176.25 177.75 1.50 29698 57 162 269 123 783 BX110 177.75 179.40 1.65 29699 52 143 224 145 719 BX111 179.40 179.90 0.50 29700 138 672 1750 276 1690 BX112 179.90 181.00 1.10 29701 247 1613 4834 491 2310 BX113 181.00 181.85 0.85 29702 443 2310 6600 532 3600 BX114 181.85 182.90 1.05 29703 345 1510 4915 330 2770 BX115 182.90 184.40 1.50 29704 17 70 66 25 149 BX116 184.40 184.60 0.20 29705 323 576 1958 195 2290 BX117 184.60 185.05 0.45 29706 66 396 1131 107 607 BX118 185.05 185.65 0.60 29707 151 1639 3400 108 621 BX119 185.65 186.40 0.75 29708 98 552 1387 161 1080 BX120 186.40 187.00 0.60 29709 50 256 674 78 388 BX121 187.00 187.45 0.45 29710 130 709 2173 230 1460 BX122 187.45 188.30 0.85 29711 105 422 1133 166 1300 BX123 188.30 190.00 1.70 29712 25 172 400 109 162 BX124 190.00 190.50 0.50 29713 184 895 3001 260 1890 BX125 190.50 191.30 0.80 29714 40 206 516 116 395 BX126 191.30 191.65 0.35 29715 143 1212 3160 435 1650 BX127 191.65 193.00 1.35 29716 26 138 330 95 285 BX128 193.00 193.70 0.70 29717 75 436 1112 172 825 BX129 193.70 194.50 0.80 29718 128 653 1583 394 1850 BX130 194.50 196.00 1.50 29719 94 429 1178 196 1140 BX131 196.00 197.15 1.15 29720 152 826 2719 372 2180 BX132 197.15 198.55 1.40 29721 71 328 937 383 2240 BX133 198.55 199.30 0.75 29722 13 50 90 23 151 BX134 199.30 200.00 0.70 29723 47 601 2203 247 805 BX135 200.00 201.00 1.00 29724 129 494 1648 285 1700 BX136 201.00 202.00 1.00 29725 160 959 3603 356 2090 BX137 202.00 202.80 0.80 29726 266 1044 3976 442 3550 BX138 202.80 203.05 0.25 29727 315 2001 9140 696 4940 BX139 203.05 203.55 0.50 29728 307 879 3251 386 3400 BX140 203.55 204.10 0.55 29729 50 195 627 96 677 BX141 204.10 205.30 1.20 29730 29 175 431 102 320 BX142 205.30 206.35 1.05 29731 33 162 438 109 505 BX143 206.35 207.05 0.70 29732 112 557 1525 414 1930 BX144 207.05 207.75 0.70 29733 63 339 943 328 1130 BX145 207.75 208.75 1.00 29734 43 516 1609 258 433 BX146 208.75 209.65 0.90 29735 121 865 2661 439 1680 BX147 209.65 210.20 0.55 29736 85 604 1889 259 1080 BX148 210.20 211.00 0.80 29737 77 337 1247 244 1200 BX149 211.00 211.60 0.60 29738 119 598 1826 324 1410 BX150 211.60 212.50 0.90 29739 59 218 492 111 745 BX151 212.50 213.10 0.60 29740 71 489 1300 312 1010 BX152 213.10 213.50 0.40 29741 123 645 1836 530 2210 BX153 213.50 214.15 0.65 29742 106 398 1124 442 1630 BX154 214.15 215.30 1.15 29743 86 303 824 365 1020 BX155 215.30 216.80 1.50 29744 16 166 512 109 151 BX156 216.80 217.60 0.80 29745 99 634 1717 320 1400 BX
APPENDIX 1: (G) River Valley Intrusion - Group-1 Data RV00-22
Sample From To Interval Tag No. Au(ppb) Pt(ppb) Pd(ppb) Ni(ppm) Cu(ppm) Strat157 217.60 219.00 1.40 29746 35 293 859 185 597 BX158 219.00 220.00 1.00 29747 109 586 1798 258 1250 BX159 220.00 220.85 0.85 29748 75 401 1054 243 1050 BX160 220.85 221.40 0.55 29749 63 581 1708 311 1090 BX161 221.40 222.30 0.90 29750 160 742 2104 502 2090 BX162 222.30 223.00 0.70 29751 65 370 1162 259 1190 BX163 223.00 224.50 1.50 29752 24 102 194 142 392 BX164 224.50 225.70 1.20 29753 26 115 309 119 357 BX165 225.70 227.25 1.55 29754 40 171 373 151 743 BZ166 227.25 229.00 1.75 29755 21 65 110 88 414 BZ167 229.00 229.70 0.70 29756 26 79 191 94 476 BZ168 229.70 231.00 1.30 29757 12 45 68 147 164 BZ169 231.00 232.00 1.00 29758 17 56 175 176 145 BZ170 232.00 233.20 1.20 29759 9 40 70 163 84.3 BZ171 233.20 235.00 1.80 29760 20 15 19 144 90.1 FBX172 235.00 236.50 1.50 29761 13 24 19 170 114 FBX173 236.50 238.00 1.50 29762 7 21 14 123 95.6 FBX174 238.00 239.50 1.50 29763 22 28 16 137 88.9 FBX175 239.50 241.50 2.00 29764 17 0 15 148 60.4 FBX
APPENDIX 1: (G) River Valley Intrusion - Group-1 Data RV00-22
LLD Method1 Sample No. 22692 22696 29601 29607 29612 29618 29622 29635Field Name Mgab Mgab Mgab Mgab Mgab Mgab Mgab Mgab
CIPW3 OGN OGN OGN OGN GN OGN OGN OGNTexture mg-cg mg-cg mg-cg mg-cg mg-cg mg-cg mg-cg mg-cgFeature massive massive massive massive massive massive massive massiveType L L L L L L L L
Interval (m) 1.50 0.52 0.46 2.00 0.39 0.28 0.28 2.00Depth (m) 4.00 9.56 18.68 32.00 40.49 51.89 59.21 79.00Strat. Unit LU LU LU LU LU LU LU LU
0.01 1 SiO2 48.62 48.38 47.58 48.99 49.30 46.20 48.86 45.260.01 1 TiO2 0.47 0.38 0.42 0.46 0.44 0.40 0.43 0.680.01 1 Al2O3 16.84 16.74 17.80 17.08 18.18 14.64 17.98 13.580.01 1 Fe2O3* 12.11 12.16 12.14 11.75 10.87 14.22 11.51 15.560.01 1 MnO 0.17 0.18 0.18 0.17 0.16 0.19 0.16 0.210.01 1 MgO 8.74 9.10 8.37 8.54 7.47 10.01 7.65 11.010.01 1 CaO 9.32 9.20 9.31 9.20 9.70 9.18 9.62 8.400.01 1 Na2O 2.24 2.15 2.16 2.50 2.41 1.68 2.37 1.490.01 1 K2O 0.63 0.60 0.60 0.55 0.69 0.51 0.65 0.790.01 1 P2O5 0.06 0.05 0.06 0.05 0.06 0.02 0.04 0.060.03 3 CO2 0.07 0.10 0.12 0.07 0.10 0.07 0.11 0.040.01 3 S 0.06 0.03 0.06 0.04 0.07 0.05 0.09 0.080.05 2 LOI 1.82 2.19 2.17 1.82 1.73 2.37 1.85 2.37
Total: 101.02 101.12 100.80 101.11 101.01 99.41 101.12 99.42Mg# 63 64 62 63 62 62 61 62
0.007 5 Cs 0.910 1.023 0.926 0.680 0.904 0.623 0.729 1.3800.007 5 U 0.280 0.262 0.272 0.290 0.260 0.308 0.211 0.2800.050 5 Rb 18.450 17.630 18.160 15.050 20.420 13.890 17.790 25.8100.060 5 Th 1.290 1.020 1.200 1.560 1.150 0.560 1.050 1.3300.200 5 Nb 2.080 1.500 1.700 1.990 1.600 1.200 1.200 2.2200.200 5 Ta 0.100 0.240 0.220 0.100 0.230 0.220 0.220 0.1000.020 5 La 7.460 6.060 7.090 6.620 6.560 3.560 5.600 6.8600.070 5 Ce 15.470 12.730 14.560 13.860 13.790 7.680 11.380 14.4700.006 5 Pr 1.950 1.609 1.819 1.750 1.717 0.983 1.454 1.8500.500 5 Sr 251.010 239.100 234.400 286.850 281.800 174.700 285.100 145.3300.030 5 Nd 7.850 6.660 7.480 6.820 7.380 4.070 5.810 7.3404.000 5 Zr 39.890 22.100 29.800 44.090 27.800 18.600 21.900 48.0200.100 5 Hf 1.120 0.600 0.700 1.220 0.800 0.500 0.600 1.3400.010 5 Sm 1.820 1.600 1.620 1.590 1.640 1.200 1.540 1.7500.005 5 Eu 0.700 0.603 0.687 0.650 0.706 0.510 0.649 0.6700.009 5 Gd 1.960 1.752 1.843 1.780 1.940 1.264 1.658 1.9100.006 5 Tb 0.340 0.299 0.313 0.300 0.283 0.248 0.247 0.3300.008 5 Dy 2.140 1.869 1.966 1.880 1.932 1.612 1.704 2.0600.020 5 Y 12.970 11.640 11.910 11.040 11.760 9.250 10.140 11.9200.003 5 Ho 0.490 0.421 0.400 0.430 0.400 0.305 0.353 0.4600.008 5 Er 1.390 1.245 1.198 1.200 1.267 1.033 1.030 1.2600.003 5 Tm 0.210 0.169 0.178 0.190 0.172 0.159 0.172 0.2100.010 5 Yb 1.370 1.160 1.240 1.110 1.210 0.940 1.140 1.2300.003 5 Lu 0.222 0.186 0.183 0.183 0.177 0.144 0.143 0.209
7 7 Se 160 157 230 141 264 206 349 2411 4 Ni 116 237 242 87 216 238 219 158
0.04 6 Ir 0.39 0.86 0.92 0.35 0.60 1.15 1.23 0.280.13 6 Ru 0.24 1.32 2.53 0.18 1.02 1.93 1.65 0.200.08 6 Rh 0.90 1.05 1.03 0.91 0.79 1.19 1.87 0.730.14 6 Pt 21.40 19.40 15.40 13.23 13.50 18.50 16.90 9.760.11 6 Pd 20.90 19.10 13.20 13.05 13.00 16.40 14.20 12.020.71 6 Au 4.41 4.57 5.29 4.43 4.02 4.04 5.20 8.690.50 4 Cu 117.0 68.0 123.0 93.0 139.0 100.0 157.0 134.0
APPENDIX 1: (H) River Valley Intrusion - Group-2 RV00-22
LLD Method1 Sample No.Field Name
CIPW3TextureFeatureType
Interval (m)Depth (m)Strat. Unit
0.01 1 SiO20.01 1 TiO20.01 1 Al2O30.01 1 Fe2O3*0.01 1 MnO0.01 1 MgO0.01 1 CaO0.01 1 Na2O0.01 1 K2O0.01 1 P2O50.03 3 CO20.01 3 S0.05 2 LOI
Total:Mg#
0.007 5 Cs0.007 5 U0.050 5 Rb0.060 5 Th0.200 5 Nb0.200 5 Ta0.020 5 La0.070 5 Ce0.006 5 Pr0.500 5 Sr0.030 5 Nd4.000 5 Zr0.100 5 Hf0.010 5 Sm0.005 5 Eu0.009 5 Gd0.006 5 Tb0.008 5 Dy0.020 5 Y0.003 5 Ho0.008 5 Er0.003 5 Tm0.010 5 Yb0.003 5 Lu
7 7 Se1 4 Ni
0.04 6 Ir0.13 6 Ru0.08 6 Rh0.14 6 Pt0.11 6 Pd0.71 6 Au0.50 4 Cu
29645 29654 29662 29670 29676 29683 29689 29696Lgab-gab Lgab-gab gab gab-Mgab gab gab gab-Mgab gabOLGN LGN LGN OLGN LGN LGN GN GNcg-peg cg-peg cg-peg mg-cg cg-peg cg-peg mg mg
massive massive b-qtz massive b-qtz b-qtz massive massiveF F M-F M M M M-F M
1.50 2.00 2.00 2.00 2.00 0.80 0.85 0.5194.00 110.00 126.00 140.00 152.00 160.80 167.50 174.51IBZ IBZ IBZ IBZ IBZ IBZ BX BX
49.64 49.81 49.59 47.53 49.66 51.09 48.83 47.940.39 0.31 0.26 0.11 0.15 0.14 0.13 0.2322.73 23.49 20.87 21.21 20.30 21.85 16.14 12.606.85 5.99 7.52 8.18 6.65 5.52 9.03 13.080.10 0.09 0.13 0.13 0.12 0.10 0.17 0.214.52 4.32 6.52 8.06 6.90 5.63 10.23 11.4210.90 11.17 11.10 10.89 12.32 10.99 10.90 9.033.21 2.88 2.47 2.09 2.40 2.90 1.93 1.210.87 0.88 0.73 0.42 0.49 0.80 0.29 0.540.05 0.04 0.03 0.01 0.01 0.01 0.01 0.010.06 0.07 0.11 0.06 0.26 0.06 0.04 0.070.03 0.02 0.02 0.01 0.02 0.01 0.04 0.291.23 1.34 1.51 2.17 1.31 1.35 1.90 2.31
100.49 100.33 100.73 100.80 100.30 100.40 99.55 98.5661 63 67 70 71 70 73 67
0.860 0.980 0.670 0.440 0.610 0.780 0.290 0.8690.310 0.210 0.120 0.030 0.270 0.590 0.020 0.188
21.230 21.000 18.850 10.550 10.170 19.730 7.560 17.5400.940 0.700 0.490 0.130 0.280 0.620 0.060 0.4701.970 1.410 0.920 0.300 0.380 0.760 0.140 0.5000.100 0.100 0.100 0.750 0.100 0.100 0.100 0.2405.610 4.480 2.590 1.090 1.960 1.760 0.920 2.680
11.730 9.280 5.250 2.050 4.110 3.540 1.790 5.5701.470 1.160 0.660 0.260 0.540 0.450 0.240 0.718
397.210 352.720 344.290 293.970 391.890 432.550 239.320 146.1005.710 4.550 2.660 1.020 2.220 1.810 1.100 3.080
34.600 31.360 21.560 6.360 10.260 13.710 2.000 8.3001.030 0.830 0.600 0.200 0.310 0.390 0.140 0.2001.280 1.080 0.650 0.260 0.620 0.420 0.320 0.8100.640 0.520 0.370 0.230 0.390 0.320 0.260 0.3451.400 1.150 0.760 0.300 0.740 0.490 0.430 0.8720.240 0.180 0.140 0.050 0.130 0.090 0.080 0.1421.480 1.150 0.860 0.340 0.820 0.610 0.550 0.8748.650 7.000 4.860 2.070 5.210 3.480 3.360 5.8500.330 0.270 0.200 0.080 0.190 0.140 0.120 0.2240.910 0.710 0.570 0.240 0.540 0.360 0.400 0.7110.140 0.110 0.090 0.040 0.090 0.060 0.060 0.1080.910 0.720 0.520 0.240 0.580 0.380 0.410 0.7300.146 0.106 0.083 0.041 0.094 0.062 0.064 0.106
97 89 63 26 98 66 252 221944 27 40 81 27 19 68 419
2.95 1.05 3.18 6.09 2.32 1.70 1.53 5.432.13 0.93 1.11 1.60 1.58 3.12 0.55 1.4713.50 2.44 11.67 24.80 7.44 5.73 6.35 25.10
168.60 11.78 66.00 177.30 110.20 60.60 74.50 332.001864.00 10.26 85.20 188.00 200.00 125.50 164.20 763.00
8.18 2.54 2.64 2.96 14.90 8.20 22.50 54.8040.5 47.9 36.0 13.6 95.9 48.9 262.0 1820.0
APPENDIX 1: (H) River Valley Intrusion - Group-2 RV00-22
LLD Method1 Sample No.Field Name
CIPW3TextureFeatureType
Interval (m)Depth (m)Strat. Unit
0.01 1 SiO20.01 1 TiO20.01 1 Al2O30.01 1 Fe2O3*0.01 1 MnO0.01 1 MgO0.01 1 CaO0.01 1 Na2O0.01 1 K2O0.01 1 P2O50.03 3 CO20.01 3 S0.05 2 LOI
Total:Mg#
0.007 5 Cs0.007 5 U0.050 5 Rb0.060 5 Th0.200 5 Nb0.200 5 Ta0.020 5 La0.070 5 Ce0.006 5 Pr0.500 5 Sr0.030 5 Nd4.000 5 Zr0.100 5 Hf0.010 5 Sm0.005 5 Eu0.009 5 Gd0.006 5 Tb0.008 5 Dy0.020 5 Y0.003 5 Ho0.008 5 Er0.003 5 Tm0.010 5 Yb0.003 5 Lu
7 7 Se1 4 Ni
0.04 6 Ir0.13 6 Ru0.08 6 Rh0.14 6 Pt0.11 6 Pd0.71 6 Au0.50 4 Cu
29702 29707 29717 29721 29733 29744 29753gab-Lgab-Mgab gab gab gab gab-Mgab-Lgab gab gab
LGN GN GN LGN G OLGN OGNmg mg mg fg-mg mg mg mg
massive massive massive massive massive massive massiveM-F M M M M-F M M0.85 0.48 0.70 0.51 0.70 0.37 0.23
181.85 185.58 193.70 198.01 207.75 215.87 224.93BX BX BX BX BX BX BX
48.81 49.80 50.41 50.58 50.61 49.40 45.790.14 0.19 0.17 0.16 0.28 0.22 0.27
20.48 17.26 16.19 19.13 10.95 19.24 16.408.70 10.22 10.45 7.99 13.99 8.67 11.430.12 0.17 0.18 0.14 0.20 0.15 0.185.98 8.36 9.69 7.73 11.76 8.01 10.549.67 10.64 9.63 10.21 7.88 10.27 7.892.70 2.18 1.89 2.62 1.01 2.63 2.360.79 0.38 0.47 0.45 0.72 0.58 0.890.01 0.01 0.01 0.01 0.02 0.01 0.030.02 0.06 0.04 0.07 0.05 0.09 0.100.78 0.79 0.18 0.05 0.47 0.01 0.341.46 1.31 2.03 1.69 2.42 1.89 2.81
98.86 100.52 101.12 100.72 99.83 101.07 98.5862 66 68 69 66 68 68
0.520 0.363 0.530 0.556 1.220 0.605 1.5710.080 0.133 0.090 0.122 1.120 0.123 2.80023.450 10.020 13.670 13.210 26.760 17.880 29.7200.210 0.310 0.290 0.340 1.560 0.210 0.5700.320 0.400 0.340 0.400 1.420 0.200 0.8000.100 0.100 0.100 0.170 0.100 0.100 0.2202.270 2.220 2.440 2.740 4.160 2.300 6.0904.620 4.520 4.720 5.480 8.640 4.570 12.0400.580 0.579 0.600 0.682 1.070 0.591 1.435
450.000 369.700 314.510 425.000 153.260 401.100 382.4002.310 2.530 2.370 2.750 4.000 2.520 5.9009.560 5.000 8.810 5.300 26.180 4.400 15.3000.270 0.200 0.260 0.200 0.780 0.200 0.5000.540 0.730 0.560 0.740 0.950 0.640 1.2600.500 0.426 0.370 0.392 0.360 0.445 0.6990.600 0.666 0.660 0.712 1.050 0.807 1.3120.110 0.116 0.120 0.117 0.190 0.140 0.2070.680 0.828 0.750 0.768 1.170 0.880 1.3174.000 5.230 4.680 4.630 7.290 5.570 7.8700.150 0.185 0.180 0.156 0.300 0.201 0.2800.440 0.609 0.500 0.541 0.820 0.611 0.8410.070 0.086 0.080 0.072 0.150 0.105 0.1350.430 0.610 0.550 0.590 0.910 0.710 0.9500.072 0.095 0.095 0.092 0.158 0.095 0.1625230 5792 963 317 2183 40 1837532 615 172 261 328 151 341
54.40 5.13 8.42 27.60 7.99 6.14 8.2415.60 1.54 4.15 11.20 3.72 2.83 2.5194.47 25.20 40.30 125.40 30.82 22.80 38.10
2375.00 718.00 439.00 1085.00 324.00 278.00 347.006670.00 1733.00 1099.00 3593.00 872.00 795.00 1102.00376.00 246.00 60.60 65.80 62.70 47.20 48.103600.0 2700.0 825.0 377.0 1130.0 20.0 348.0
APPENDIX 1: (H) River Valley Intrusion - Group-2 RV00-22
LLD Method1 Sample No.Field Name
CIPW3TextureFeatureType
Interval (m)Depth (m)Strat. Unit
0.01 1 SiO20.01 1 TiO20.01 1 Al2O30.01 1 Fe2O3*0.01 1 MnO0.01 1 MgO0.01 1 CaO0.01 1 Na2O0.01 1 K2O0.01 1 P2O50.03 3 CO20.01 3 S0.05 2 LOI
Total:Mg#
0.007 5 Cs0.007 5 U0.050 5 Rb0.060 5 Th0.200 5 Nb0.200 5 Ta0.020 5 La0.070 5 Ce0.006 5 Pr0.500 5 Sr0.030 5 Nd4.000 5 Zr0.100 5 Hf0.010 5 Sm0.005 5 Eu0.009 5 Gd0.006 5 Tb0.008 5 Dy0.020 5 Y0.003 5 Ho0.008 5 Er0.003 5 Tm0.010 5 Yb0.003 5 Lu
7 7 Se1 4 Ni
0.04 6 Ir0.13 6 Ru0.08 6 Rh0.14 6 Pt0.11 6 Pd0.71 6 Au0.50 4 Cu
29756 29762 RV22-01 RV22-02 RV22-03gab-Mgab gneiss
GN LGN - - -mg fg-mg fg fg fg
sheared foliated foliated foliated foliated; blue qtzM-F FBX gneiss gneiss gneiss0.70 1.50 0.30 0.26 0.22
229.70 238.00 244.30 250.26 256.00BZ FBX FW FW FW
51.18 50.59 48.69 51.69 55.700.34 0.71 0.45 0.46 0.37
15.79 18.00 19.22 18.12 19.3811.28 10.40 11.38 10.40 7.250.17 0.13 0.13 0.13 0.088.06 7.21 8.45 7.32 4.979.98 6.18 3.76 5.63 4.442.10 3.22 3.67 3.25 4.641.00 1.34 1.20 1.29 1.140.01 0.06 0.05 0.03 0.050.04 0.03 0.02 0.02 0.030.15 0.43 0.47 0.36 0.260.98 2.33 3.49 2.48 2.27
100.91 100.19 100.49 100.79 100.2762 62 63 62 61
1.720 2.310 2.170 2.292 1.9500.510 0.820 1.500 0.914 1.93335.160 44.470 36.000 37.360 30.9300.480 1.120 1.120 1.380 2.2800.380 1.310 180.000 1.100 1.8000.100 0.100 0.270 0.270 0.4103.130 17.410 22.400 20.460 38.8006.310 29.690 39.900 36.370 65.6200.830 3.280 4.180 3.898 6.571
450.000 450.000 726.000 887.700 1065.0003.550 11.300 14.600 13.200 21.86011.620 30.550 30.600 28.800 55.5000.410 0.920 0.900 0.900 1.8000.980 1.600 2.100 1.840 2.6000.570 1.740 1.700 2.126 2.2961.150 1.180 1.430 1.367 1.8760.200 0.160 0.198 0.190 0.2111.250 0.900 1.160 1.040 1.0627.790 5.640 7.000 5.910 6.0900.300 0.200 0.246 0.214 0.2230.860 0.630 0.773 0.742 0.7080.140 0.100 0.130 0.143 0.1270.880 0.760 0.940 1.050 0.8400.147 0.136 0.159 0.167 0.154598 292 217 277 18494 123 200 191 133
1.46 0.19 0.13 0.28 0.100.87 0.36 0.36 0.59 0.328.50 0.69 0.19 0.20 0.11
68.30 3.53 3.01 3.10 1.71214.00 4.87 3.90 3.15 2.1218.50 1.71 0.36 0.36 0.36476.0 95.6 61.0 96.0 60.0
APPENDIX 1: (H) River Valley Intrusion - Group-2 RV00-22
538
APPENDIX 2:
PETROGRAPHIC DESCRIPTIONS
A) Nipissing Gabbro intrusions (Hand Specimens) 539 B) River Valley intrusion (Matrix/Fragment Specimens, DDH RV00-22) 553 NOTES AND KEY: 1specific pyroxene not discernable 2primarily after pyroxene and biotite - not included in the mode total "x"=present in trace amounts "msv"=massive Field Names: A = aplite; CM=chilled margin; G=gabbro; LG=leucogabbro; OPXG=orthopyroxene gabbro; MG=melagabbro; mtG=mt-bearing gabbro GG=Granophyric Gabbro; vtG=vari-textured Gabbro; qtzG=quartz Gabbro CIPW Names: OGN=olivine gabbronorite; MGN=melagabbronorite; GN=gabbronorite; OMGN=olivine melagabbronorite OLGN=olivine leucogabbronorite; LG=leucogabbro; LGN=leucogabbronorite Normatives and CIPW Classification: Q=quartz; N=nepheline; H=hypersthene; O=olivine; C=corundum su=silica-undersaturated (alkali basalt); ss=silica-saturated (olivine tholeiites); so=silica-oversaturated (quartz tholeiites) Textures (petrographic descriptions): EA=extensively altered g-h=granular hypidiomorphic d-i=diabasic-isogranular g-i=granular-idiomorphic qcpV=contains qtz-cpy veins gb=granoblastic g-m=granular mosaic porph=porphyritic
Sample JB97-65 JB97-78B JB97-48 JB97-49 JB98-207 JB98-224 JB98-239B JB98-239CTownship Wells Waters Wells Wells Kelly Janes Kelly Kelly
Intrusion/Area 1W 17C 1W 1W 10E 8E 10E 10EField Name A A CM CM CM CM CM CMRock Name A A CM CM CM CM CM CM
Grain fg fg-mg fg fg fg vfg vfg fgMain Texture g-i g-m d-i d-i d-i d-i d-i d-i
2nd Texture porph porph porphComments qtz-carb vein
CIPW Name - - G G G G G GNormatives Q-H Q-H-C Q-H Q-H Q-H Q-H Q-H Q-H
MineralsQuartz 50 35 2 2 1 3 2 2
Plagioclase 30 43 40 40 50 40 43 43K-spar 20 20
1Pyroxene 53 53 47OrthopyroxeneClinopyroxene 49 5 55 55
PigeoniteGranophyre x xMyrmekite x x
Biotite 1 x x x x xEpidote x 5 5 x 3 x xApatite x x x x xTitanite x x
LeucoxeneZircon
Opaques x 1 x x x 2 x xAlteration
2Amphibole 53 53 45 45 45 45Carbonate x2Chlorite x 1 x x x x x xSericite x x x x x x x x
Saussurite x x x x x x x xTotal Mode: 100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-240 JB97-40B JB97-55 JB97-56 JB97-57 JB97-58 JB97-62 JB97-77BKelly Janes Wells Wells Wells Wells Wells Waters10E 8E 1W 1W 1W 1W 1W 17CCM G G G G G G GCM G G G G G G Gvfg mg mg mg mg mg mg mgd-i g-h g-h g-i g-i g-i g-i g-m
porphhigh epidote
G G G G G G G GNQ-H Q-H Q-H Q-H Q-H Q-H Q-H H-O
2 5 x x x x x43 27 45 45 50 50 50 42
135 46
5 5 555 50 50 50 50 45
x x x x xx
x x x x x x 10x 30 x x x x xx x x x
xx 3 x x x x x 1
45 40 45 45 40 40x x
x x x x x x x xx x x x x x x xx x x x x x x x
100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-84D JB97-87A JB97-87B JB97-87J JB97-87K JB97-99 JB97-103ELouise Janes Janes Janes Janes Scadding Kelly
13C 8E 8E 8E 8E 16E 10EG G G G G G G
MG GN GN G G CM Gmg mg mg mg mg fg mgg-m g-i g-i g-h g-h d-i g-i
porph porph
G G G G G GN GQ-H Q-H Q-H Q-H Q-H H-O Q-H
2 2 1 4 5 10 x27 43 43 32 35 40 50x
47 45 59 542 5 2 5
70 5 3 50 45
1 x
x xx x x 3 2 x x
x x xx
1 1 2 2 2 x x
60 45 35 55 55 40 40x xx x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-106A JB97-106C JB98-114 JB98-150 JB98-151C JB98-175 JB98-178Janes Janes Waters Lorne Lorne Curtin Curtin
8E 8E 17C 12SW 12SW 5SW 5SWG G G G G G GG G MG MG MG G G
mg fg-mg mg mg mg mg mgg-h g-h g-m g-h g-h g-h g-h
G G GN LG GN G GQ-H Q-H H-O Q-H H-O Q-H Q-H
3 5 1 1 x x40 40 40 25 24 49 49
46 53 60 502
74 75 48
1 1 1
x x x x10 x x x x x xx x x x x
x x
1 1 x x x x x
46 50 55 45 50x
x x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-194 JB98-195 JB98-196 JB98-198 JB98-199 JB98-200 JB98-201 JB98-202Kelly Kelly Kelly Kelly Kelly Kelly Kelly Kelly10E 10E 10E 10E 10E 10E 10E 10EG G G G G G G G
CM G G OPXG G G OPXG Gfg fg-mg mg mg mg mg mg mgd-i d-i g-i g-i g-i g-i g-i g-i
porph porph
G G G G G GN G GQ-H Q-H Q-H Q-H Q-H H-O Q-H Q-H
3 5 x 1 x x 150 47 50 45 55 45 45 44
5 5 5 5 5 547 48 45 50 39 50 50 50
x x x x x xx x x x x x xx x
x x x x x x x x
x x 5 45 30 45 10 30
x x x x x x x xx x x x x x x xx x x x x x x x
100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-203 JB98-205 JB98-206 JB98-209C JB98-210A JB98-228 JB98-229 JB98-230Kelly Kelly Kelly Louise Louise Curtin Curtin Curtin10E 10E 10E 13C 13C 4SW 4SW 4SWG G G G G G G G
OPXG mtG OPXG MG CM OPXG OPXG Gmg mg mg mg vfg-fg mg mg mgg-i g-i g-i EA d-i g-h g-h g-i
porph porph porph porph
G G G G G GN GN GNQ-H Q-H Q-H Q-H Q-H H-O H-O H-O
x x 20 5 x 1 x45 49 45 19 45 48 45 45
60 49 555 5 5 5 5
50 46 50 44 45
x x x xx x 2 3 x
x 1 1 x
x x 1 1 x x x
35 25 45 60 45 35x
x x x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-231 JB98-239D JB98-239E JB98-239F JB97-50 JB97-43B JB97-43DCurtin Kelly Kelly Kelly Wells Janes Janes4SW 10E 10E 10E 1W 8E 8E
G G G G GG OPXG OPXGG G G G GG MG OPXG
mg fg-mg mg mg mg-cg mg mgg-h g-i g-i g-i g-h g-h g-h
porph porph
G GN G G G G GQ-H H-O Q-H Q-H Q-H Q-H Q-H
5 1 1 x 5 6 548 49 45 50 48 31 37
45 54 522
50 54 50 40x
2 x 3
x x x xx x x x 2 3 1x x x
x
x x x x 5 3 3
45 30 35 35 50 45x
x x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-103B JB97-103D JB97-106B JB97-107 JB97-108 JB98-182 JB98-204Kelly Kelly Janes Janes Janes Curtin Kelly10E 10E 8E 8E 8E 5SW 10E
OPXG OPXG OPXG OPXG OPXG OPXG OPXGOPXG OPXG OPXG OPXG OPXG OPXG OPXG
mg mg mg fg-mg mg mg mgg-i g-i g-h g-i g-m g-h g-i
porph porph porph porph porph porphprimary minerals
GN G G G G GN GH-O Q-H Q-H Q-H Q-H H-O Q-H
x 1 5 1 2 x x50 55 38 38 40 45 45
40 40 5 435 5 5 10 17 2 5
45 39 10 10 35 10 50
1 x
x x x xx x x x x x xx x x
x
x x 1 1 1 x x
5 10 40 5 30 x
x x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-47 JB97-104 JB98-115 JB97-80A JB98-197 JB98-124 JB97-45 JB97-51Ermatinger Janes Janes Louise Kelly Kirkwood Moncrieff Wells
6NW 8E 9E 13C 10E 1W 14NW 1WLG LG LG MG mtG qtzG vtG vtGG G G MG G G G vtG
mg mg mg mg mg mg mg mgg-m g-h g-h g-h g-i g-h g-h g-i
porph
G G G G G G G LGQ-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H
5 5 1 x 1 2 10 343 48 44 39 55 45 50 52
48 43 375 5
55 60 39 48 45
3 x x x x
x x x xx 3 x x x 2 x
x x x xx
x1 1 x 1 x x 1 x
35 43 50 40 25 x 37 35
x x x x x x x xx x x x x x x xx x x x x x x x
100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-52 JB97-59 JB97-60 JB97-64 JB97-66A JB97-98 JB97-100 JB97-105Wells Wells Wells Wells Wells Scadding Scadding Janes1W 1W 1W 1W 1W 16E 16E 8EvtG vtG vtG vtG vtG vtG vtG vtGvtG vtG vtG vtG vtG G G Gmg mg mg mg mg mg mg mgg-i g-i g-i g-i g-i g-h g-h g-h
G G G LG LG G G GQ-H Q-H Q-H Q-H Q-H Q-H Q-H Q-H
1 x x 2 10 1 10 550 50 50 50 40 44 35 30
505 5
49 45 45 48 45 55 45
x x xx
x x x x xx x x x 5 x 10 15x x x x xx x
xx x x x x x x x
30 40 40 35 30 35 40 55
x x x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-43C JB97-109 JB97-87C JB97-87D JB97-87E JB97-87F JB97-87GJanes Janes Janes Janes Janes Janes Janes
8E 8E 8E 8E 8E 8E 8EOPXG OPXG G G G G G
GN G GN GN MG G GNmg mg mg mg mg mg mgg-h g-h g-h g-i g-i g-h g-h
porph porph porph porph porphhigh epidote
G LG G G G G GQ-H Q-H Q-H Q-H Q-H Q-H Q-H
2 5 3 3 10 5 1039 25 35 33 20 35 32
46 33 54 47 42 53 345 3 2 5 5
5 10 5 10
x x x 1
x 2 x x x x3 20 3 5 11 5
x x xx
5 15 2 5 2 2 3
45 33 40 40 40 50 40x xx x x x x xx x x x x xx x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB97-87H JB97-87I JB97-9A JB97-12 JB98-121B1 JB98-121B2 JB98-225AJanes Janes Kirkwood Kirkwood Wells Wells Curtin
8E 8E 1W 1W 1W 1W 4SWG G OPXG vtG vtG vtG GG GN OPXG vtG vtG vtG OPXG
mg mg mg mg mg mg mgg-h g-h g-h g-h qcpV qcpV g-h
porph porph porph
G G - - - - -Q-H Q-H - - - - -
5 5 x 5 25 25 x30 37 45 35 15 15 45
10 5 548 45 55 55
2 5 52 3 50 37 45
x xx
x x 3 x10 5 x 10 x x xx x x x x x
x x x
5 3 x x x x 5
45 45 40 45 45 50 5x xx x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-186 JB97-46 JB97-103A JB97-103C JB98-209A JB98-209B JB98-209DCurtin Moncrieff Kelly Kelly Louise Louise Louise5SW 14NW 10E 10E 13C 13C 13C
A vtG OPXG OPXG G G GA G OPXG OPXG EA EA EA
fg-mg mg mg mg mg mg mgg-i g-h g-i g-i EA EA EA
porph porphhigh sulphide msv sulphide msv sulphide
- - - - - - - - - - - - - -
30 15 x x30 40 50 5040
355 5
45 45
x x xx 10 x x
x x
x x x
x 35 35 40xx x xx x xx x x
100 100 100 100 0 0 0
APPENDIX 2: (A) Nipissing Gabbro Intrusions
SampleTownship
Intrusion/AreaField NameRock Name
GrainMain Texture
2nd TextureComments
CIPW NameNormatives
MineralsQuartz
PlagioclaseK-spar
1PyroxeneOrthopyroxeneClinopyroxene
PigeoniteGranophyreMyrmekite
BiotiteEpidoteApatiteTitanite
LeucoxeneZircon
OpaquesAlteration
2AmphiboleCarbonate2ChloriteSericite
SaussuriteTotal Mode:
JB98-212A JB97-72B JB98-165 JB98-117B JB98-117C JB98-190E JB98-138Louise Louise Waters Nairn Nairn Rathbun Davis
13C 13C 17C 18SW 18SW 19E -OPXG G LG G G G mtG
MG GN EA G MG EA mtGmg mg fg-mg mg-cg mg fg-mg mgEA g-h EA g-i g-h EA g-h
porphhigh sulphide high sulphide high sulphide high sulphide
- - - - - - - - - - - - - -
2 2 6 10 10 5 220 30 1 37 27 15 40
10 575 60 2 25 20
3 515 53
x 16 2 2 3x 5 1 1 2 5
x x x
3 x 75 15 15 75 x
80 60 2 32 20 5 40x x
x x x x x xx x x x x x xx x x x x x x
100 100 100 100 100 100 100
APPENDIX 2: (A) Nipissing Gabbro Intrusions
Sample DDH/Area Type FieldName Strat RockName Grain Texture %Plag %Kspar22692 RV00-22 - melagabbro LU gabbronorite mg-cg granular-idiomorphic 50 -29607 RV00-22 - melagabbro LU gabbronorite mg granular-hypidiomorphic 40 -29635 RV00-22 - melagabbro LU gabbronorite mg granular-hypidiomorphic 40 -29645 RV00-22 - leucogabbro IBZ leucogabbro mg granular-idiomorphic 70 -29654 RV00-22 - leucogabbro IBZ leucogabbro mg granular-idiomorphic 60 -29662 RV00-22 - gabbro BX gabbro mg recrystallized 47 -29670 RV00-22 - melagabbro BX gabbro mg granular-idiomorphic 55 -29676 RV00-22 - gabbro BX gabbro mg granular-idiomorphic 55 -29683 RV00-22 - gabbro BX gabbro mg recrystallized 55 -29689 RV00-22 - gabbro BX gabbro mg granular-idiomorphic 50 -29697 RV00-22 - gabbro BX gabbro fg diabasic-isogranular 35 -29702 RV00-22 - gabbro BX gabbro mg-cg granular-idiomorphic 55 -29705 RV00-22 - gabbro BX gabbro mg recrystallized 55 -29717 RV00-22 - gabbro BX gabbro mg granular-idiomorphic 55 -29723 RV00-22 - gabbro BX gabbro mg granular-hypidiomorphic 52 -29733 RV00-22 - gabbro BX melagabbro mg granular-hypidiomorphic 10 -29743 RV00-22 - gabbro BX melagabbro fg-mg extensively recrystallized 10 -29751 RV00-22 - gabbro BX gabbro fg-mg extensively recrystallized 45 -29756 RV00-22 - gabbro BZ melagabbro fg-mg extensively recrystallized 10 -29762 RV00-22 - gneiss FW schist fg extensively recrystallized - -
SZF-01 South Zone fragment melagabbro BX melagabbro fg recrystallized 20 -SZM-01 South Zone matrix gabbro BX gabbro mg granular-hypidiomorphic 50 -SZF-02 South Zone fragment melagabbro BX melagabbro mg extensively recrystallized 15 -SZM-02 South Zone matrix gabbro BX gabbro mg granular-hypidiomorphic 45 -SZF-03 South Zone fragment melagabbro BX melagabbro mg recrystallized 25 -SZM-03 South Zone matrix gabbro BX gabbro mg granular-hypidiomorphic 38 -SZF-04 South Zone fragment melagabbro BX melagabbro mg extensively recrystallized 10 -SZM-04 South Zone matrix leucogabbro BX leucogabbro mg-cg granular-hypidiomorphic 70 -SZF-05 South Zone fragment gabbro BX gabbro mg extensively recrystallized 45 -SZM-05 South Zone matrix gabbro BX gabbro mg granular-hypidiomorphic 45 -CZF-01 Central Zone fragment gabbro BX gabbro mg extensively recrystallized 35 -CZM-01 Central Zone matrix leucogabbro BX gabbro mg-cg granular-hypidiomorphic 30 -CZF-02 Central Zone fragment gabbro BX gabbro mg extensively recrystallized 35 -CZM-02 Central Zone matrix leucogabbro BX gabbro mg granular-hypidiomorphic 30 -CZF-03 Central Zone fragment gabbro BX gabbro mg extensively recrystallized 35 -CZM-03 Central Zone matrix gabbro BX gabbro mg granular-hypidiomorphic 30 -
APPENDIX 2: (B) River Valley Intrusion - Matrix/Fragment RV00-22
Sample2269229607296352964529654296622967029676296832968929697297022970529717297232973329743297512975629762
SZF-01SZM-01SZF-02SZM-02SZF-03SZM-03SZF-04SZM-04SZF-05SZM-05CZF-01CZM-01CZF-02CZM-02CZF-03CZM-03
Qtz %Ol %Pyx Cpx Opx - - 50 x nd - - 60 x nd - - 60 x nd - - 28 x nd - - 20 x nd - - 50 x nd - - 45 x1 x2 - - 40 x nd - - 45 x nd - - 50 x nd - - 47 x nd - - 40 x nd - - 45 x nd - - 38 x nd - - 40 x nd - - 82 x nd - - 45 x nd - - 45 x nd - - 68 x nd - - - - - - - 79 x nd - - 50 x nd - - 84 x nd - - 53 x nd - - 75 x nd - - 50 x nd - - 72 x nd - - 25 x nd - - 47 x nd - - 50 x nd - - 38 x nd - - 45 x nd - - 38 x nd - - 45 x nd - - 38 x nd - - 45 x nd
Major (>10%)
APPENDIX 2: (B) River Valley Intrusion - Matrix/Fragment RV00-22
Sample2269229607296352964529654296622967029676296832968929697297022970529717297232973329743297512975629762
SZF-01SZM-01SZF-02SZM-02SZF-03SZM-03SZF-04SZM-04SZF-05SZM-05CZF-01CZM-01CZF-02CZM-02CZF-03CZM-03
Pig Qtz Amp Ol Biot Ox Sulp Ep Ep Ap Qtz Biot Ox Sulp Zr Ttn Amp Chl Sericnd - - 2 - - - - x x x x x x - - pyx pyx/plag plagnd - - 2 - - - - x x x x x x - - pyx pyx/plag plagnd - - 5 - - - - x - x x x x - - pyx pyx/plag plagnd 2 - - - - - 10 - x - - x x - x pyx pyx/plag plagnd 10 - - - - - 10 - x - x x x - - pyx pyx/plag plagnd 1 - - - - - 2 - - - - - x - - pyx pyx/plag plagnd - - - - - - - x x x - - - - pyx pyx/plag plagnd - - - - - - 5 - - x - x x - - pyx pyx/plag plagnd - - - - - - - x - x - x x - - pyx pyx/plag plagnd - - - - - - - x - - - x x - - pyx pyx/plag plagnd 5 - - - 2 1 10 - - - - - - - - pyx pyx/plag plagnd - - - - - - 5 - - x - x x - - pyx pyx/plag plagnd - - - - - - - x - - - x x - - pyx pyx plagnd - - - - - 2 5 - - x x - - - - pyx pyx/plag plagnd - - - - - 3 5 - - x x - - - - pyx pyx/plag plagnd 1 - - 5 - 2 - x - - - x - - - pyx pyx/plag plagnd 5 - - 15 - 5 20 - - - - x - - - pyx pyx/plag plagnd 3 - - 5 - 2 10 - - - - x - - - pyx pyx/plag plagnd 1 - - 10 - 1 10 - - - - - - - x pyx pyx/plag plag - - - - - - - - - - - - - - - - pyx pyx/plag plagnd - - - - - 1 - x - x - - - - - pyx pyx/plag plagnd - - - - - - - x - x - - x - x pyx pyx/plag plagnd - - - - - 1 - x - x - x x - - pyx pyx/plag plagnd - - - - - 1 1 - - x x - - - x pyx pyx/plag plagnd - - - - - - - x - x - - x - x pyx pyx/plag plagnd - - - - - 2 10 - x x - - - - - pyx pyx/plag plagnd 5 - - 10 - 3 5 - x - - - - x - pyx pyx/plag plagnd - - - - - 2 3 - - x x - - - - pyx pyx/plag plagnd 3 - - - - 2 3 - x - - - - - x pyx pyx/plag plagnd - - - - - - 5 - x x - - x - x pyx pyx/plag plagnd 5 - - 10 - 2 10 - x - - - - - x pyx pyx/plag plagnd 1 - - 10 2 2 10 - x - - - - - - pyx pyx/plag plagnd 5 - - 10 - 2 10 - x - - - - - x pyx pyx/plag plagnd 1 - - 10 2 2 10 - x - - - - - - pyx pyx/plag plagnd 5 - - 10 - 2 10 - x - - - - - x pyx pyx/plag plagnd 1 - - 5 1 1 5 - x - - - - - - pyx pyx/plag plag
SecondaryAccessory (<1%)Minor (<10%)
APPENDIX 2: (B) River Valley Intrusion - Matrix/Fragment RV00-22
Sample2269229607296352964529654296622967029676296832968929697297022970529717297232973329743297512975629762
SZF-01SZM-01SZF-02SZM-02SZF-03SZM-03SZF-04SZM-04SZF-05SZM-05CZF-01CZM-01CZF-02CZM-02CZF-03CZM-03
Sauss Alteration Featuresplag plag-->actin/hbld; pyx-->actinplag plag-->actin/hbld; pyx-->actinplag plag-->actin/hbld; pyx-->actinplag plag-->sauss; pyx-->actinplag plag-->sauss/hbld; pyx-->actin/hbld; plag-->fspar+qtzplag plag-->sauss/hbld; pyx-->actin/hbldplag plag-->sauss/hbld; pyx-->actin/hbld; plag-->albite+qtzplag plag-->sauss/hbld; pyx-->actin/hbld; plag-->albite+qtzplag plag-->sauss/hbld; pyx-->actin/hbldplag plag-->sauss/hbld; pyx-->actin/hbldplag plag-->sauss/hbld; pyx-->actin/hbldplag plag-->sauss/hbld; pyx-->actin/hbld; plag-->albite+qtzplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld/exsolution; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag extensively recrystallized - probably orthogneissplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbldplag plag-->sauss/actin/hbld; pyx-->actin/hbld
APPENDIX 2: (B) River Valley Intrusion - Matrix/Fragment RV00-22
Sample2269229607296352964529654296622967029676296832968929697297022970529717297232973329743297512975629762
SZF-01SZM-01SZF-02SZM-02SZF-03SZM-03SZF-04SZM-04SZF-05SZM-05CZF-01CZM-01CZF-02CZM-02CZF-03CZM-03
General Features Commentsrelict igneous textures altered olivines completely gone to tremolite?relict igneous textures altered olivines completely gone to tremolite?relict igneous textures altered olivines completely gone to tremolite?relict igneous textures much more epidote than in previous samplesrelict igneous textures much more epidote than in previous samplesrelict igneous textures shear zone cuts samplerelict igneous textures zones of amphibole as relict phenocrystsrelict igneous texturesrelict igneous textures cut by albite-qtz veinrelict igneous textures
granular-idiomorphic to diabase-isogranularrelict igneous textures
relict igneous textures; extensive alteration STRONGLY ALTEREDrelict igneous textures
exsolution textures of fspar-qtz in plag replacement or exsolution of plagstrongly altered and recrystallized increase in biotite - introduction of K
biotite-epidote coincident w elevated sulphide foliated mafic; anorthositic fragment in mafic hostbiotite-epidote coincident w elevated sulphide foliated; kink bands/strain zones; microshearsbiotite-epidote coincident w elevated sulphide very fg titanite; abundant primary(?) epidote
weakly foliated; rich in epidote/biotite actin-hbld-biot-ep-titan-po matrtixextensively altered
extensively altered relict igneous texturespyx extensively alterered moderately altered
plag altered to qtz-albite intergrowth altered plag-pyx; relict igneous texturespyx strongly altered relative to plag relict igneous textures
qtz-biot patches with sulphides relict igneous textureschlorite-epidote-sulphide patches relict igneous textures
edpidote with sulphide poor relict igneous texturespyx strongly altered relative to plag relict igneous textures
edpidote, chlorite, qtz and titanite with sulphide poor relict igneous texturessulphide with biotite, epidote and muscovite plag altered to qtz-albite intergrowth
poor relict igneous texturessulphide with biotite, epidote and muscovite plag altered to qtz-albite intergrowthedpidote, chlorite, qtz, biotite with sulphide poor relict igneous textures
sulphide with biotite, epidote, qtz poor relict igneous textures
APPENDIX 2: (B) River Valley Intrusion - Matrix/Fragment RV00-22
558
APPENDIX 3:
DIAMOND DRILL HOLE DATA LISTING AND DRILL CORE LOGS A) JR99-01, JR99-06 (Rastall property, Chiniguchi River intrusion) 559 B) A197 (Rauhala property, Makada Lake intrusion) 564 C) RV00-22 (Dana North Deposit, River Valley intrusion) 565
JR99-01Sample From To Interval Pd Au Pt Cu Ni
(m) (m) (m) (ppb) (ppb) (ppb) (ppm) (ppm)
1 2.50 2.95 0.45 41 0 0 63 432 2.95 3.57 0.62 94 9 15 211 773 3.57 4.11 0.54 1063 82 207 1596 12604 4.11 4.68 0.57 54 0 0 131 765 4.68 5.00 0.32 330 28 66 552 2936 5.00 5.54 0.54 381 32 74 652 3407 5.54 6.16 0.62 78 6 23 106 608 6.16 6.69 0.53 167 15 29 283 1549 6.69 7.00 0.31 46 0 0 109 65
10 7.00 7.53 0.53 23 0 0 62 41chk 10 7.00 7.53 0.53 28 0 0avg 10 7.00 7.53 0.53 25.5 0 0
11 7.53 8.00 0.47 11 0 0 53 4612 8.00 8.77 0.77 21 0 0 78 5213 8.77 9.41 0.64 45 6 15 83 5914 9.41 10.41 1.00 153 12 30 193 10415 10.41 10.89 0.48 218 14 42 239 13416 10.89 11.47 0.58 53 7 17 101 5917 11.47 12.21 0.74 31 0 0 73 5118 12.21 12.68 0.47 309 18 55 318 16419 12.68 13.33 0.65 149 31 40 835 319
chk 19 12.68 13.33 0.65 140 30 36avg 19 12.68 13.33 0.65 144.5 30.5 38
20 13.33 14.00 0.67 108 48 43 997 41021 14.00 14.45 0.45 105 49 60 1635 65422 14.45 15.11 0.66 74 37 41 1297 49923 15.11 15.61 0.50 100 53 37 1474 64624 15.61 16.21 0.60 125 52 34 1632 63925 16.21 16.56 0.35 137 32 37 874 358
chk 25 16.21 16.56 0.35 123 25 30avg 25 16.21 16.56 0.35 130 28.5 33.5
26 16.56 17.00 0.44 136 74 56 2191 84427 17.00 17.43 0.43 183 105 82 3390 131828 17.43 17.95 0.52 148 105 60 2991 120629 17.95 18.45 0.50 233 178 104 4938 209730 18.45 18.88 0.43 199 125 93 3593 152031 18.88 19.33 0.45 196 115 54 3407 109632 19.33 19.68 0.35 95 55 41 1863 69733 19.68 20.00 0.32 140 91 57 2948 119334 20.00 20.50 0.50 149 104 52 3503 150735 20.50 21.25 0.75 82 54 61 1759 78236 21.39 21.99 0.60 258 222 126 5766 271737 21.99 22.50 0.51 292 234 133 6235 2615
chk 37 21.99 22.50 0.51 269 197 115 6774 2683avg 37 21.99 22.50 0.51 280.5 215.5 124
38 22.50 23.00 0.50 277 213 125 6774 2683
APPENDIX 3: (A) Drill Hole Composite - Chiniguchi River Intrusion
JR99-01Sample From To Interval Pd Au Pt Cu Ni
(m) (m) (m) (ppb) (ppb) (ppb) (ppm) (ppm)39 23.00 23.69 0.69 267 192 107 5596 228740 23.69 24.46 0.77 237 190 113 5657 247541 24.46 25.07 0.61 243 178 106 4578 194842 25.07 25.72 0.65 243 163 103 4632 214743 25.72 26.51 0.79 287 218 132 5861 239344 26.51 27.20 0.69 252 264 115 5664 216945 27.20 27.91 0.71 267 162 116 4481 207046 27.91 28.47 0.56 95 42 23 4733 184547 28.47 29.28 0.81 199 96 63 6198 203348 29.28 30.15 0.87 190 76 53 4489 162549 30.15 30.89 0.74 233 95 63 4476 188050 30.89 31.50 0.61 147 74 36 2896 107751 31.50 32.00 0.50 201 77 56 4070 162052 32.00 32.75 0.75 626 267 181 7344 318253 32.75 33.44 0.69 645 279 198 6382 266554 33.44 34.44 1.00 682 218 180 5112 211055 34.44 35.00 0.56 905 220 206 5511 2245
chk 55 34.44 35.00 0.56 731 153 136avg 55 34.44 35.00 0.56 818 186.5 171
56 35.00 35.75 0.75 1082 270 227 7255 345057 35.75 36.42 0.67 1205 245 224 5756 257858 36.42 37.30 0.88 1660 369 311 11973 336559 37.30 38.00 0.70 1797 445 378 11329 464360 38.00 38.74 0.74 1944 387 364 11979 549361 38.74 39.49 0.75 1862 315 344 9825 321562 39.49 40.13 0.64 1834 207 325 7705 311163 40.13 40.73 0.60 3527 272 486 10491 5214
chk 63 40.13 40.73 0.60 3928 309 516avg 63 40.13 40.73 0.60 3727.5 290.5 501
64 40.73 41.00 0.27 5830 329 571 4232 3493chk 64 40.73 41.00 0.27 5697 267 627avg 64 40.73 41.00 0.27 5763.5 298 599
65 41.00 41.62 0.62 5394 293 589 13885 4312chk 65 41.00 41.62 0.62 5132 368 491avg 65 41.00 41.62 0.62 5263 330.5 540
66 41.62 41.87 0.25 2083 30 274 101016 171767 41.87 42.09 0.22 4513 35 510 7051 2406
chk 67 41.87 42.09 0.22 4551 27 459avg 67 41.87 42.09 0.22 4532 31 484.5
68 42.09 42.57 0.48 2501 81 347 19088 206469 42.57 43.24 0.67 2762 200 387 8380 229470 43.24 43.59 0.35 3484 26 565 2261 2337
chk 70 43.24 43.59 0.35 2628 20 427avg 70 43.24 43.59 0.35 3056 23 496
71 43.59 43.85 0.26 1733 21 241 988 120672 43.85 44.77 0.92 1890 23 280 759 892
chk 72 43.85 44.77 0.92 2260 15 282
APPENDIX 3: (A) Drill Hole Composite - Chiniguchi River Intrusion
JR99-01Sample From To Interval Pd Au Pt Cu Ni
(m) (m) (m) (ppb) (ppb) (ppb) (ppm) (ppm)avg 72 43.85 44.77 0.92 2075 19 281
73 44.77 45.25 0.48 276 0 52 163 53774 45.25 46.35 1.10 1792 18 251 110 147875 46.35 47.11 0.76 3709 181 462 5221 3168
chk 75 46.35 47.11 0.76 3456 133 420avg 75 46.35 47.11 0.76 3582.5 157 441
76 47.11 47.87 0.76 1996 157 274 3611 146677 47.87 48.72 0.85 2701 191 342 5624 220678 48.72 49.76 1.04 3299 207 417 6235 2633
chk 78 48.72 49.76 1.04 3112 199 410avg 78 48.72 49.76 1.04 3205.5 203 413.5
79 49.76 50.05 0.29 2151 165 326 4100 174380 50.05 51.08 1.03 62 12 21 170 9381 51.08 52.03 0.95 0 7 0 126 64
chk 81 51.08 52.03 0.95 22 5 0avg 81 51.08 52.03 0.95 11 6 0
82 52.03 53.19 1.16 22 5 0 115 7483 53.19 54.48 1.29 18 0 16 118 7784 54.48 55.75 1.27 13 0 0 86 6585 55.75 56.70 0.95 11 0 0 116 7786 56.70 57.67 0.97 16 0 0 123 7687 57.67 58.79 1.12 14 0 0 125 8588 58.79 59.95 1.16 13 0 0 105 7189 59.95 60.96 1.01 12 0 0 103 7490 60.96 62.10 1.14 12 0 0 102 70
chk 90 60.96 62.10 1.14 12 0 0avg 90 60.96 62.10 1.14 12 0 0
91 62.10 62.69 0.59 13 0 0 136 7092 62.69 62.93 0.24 0 9 0 240 7993 62.93 64.01 1.08 23 0 15 103 7494 64.01 65.06 1.05 54 7 16 148 7695 65.06 66.35 1.29 244 15 28 415 14596 66.35 67.23 0.88 181 5 0 119 10197 67.23 68.08 0.85 14 0 0 90 65
APPENDIX 3: (A) Drill Hole Composite - Chiniguchi River Intrusion
JR99-06Sample From To Interval Pd Au Pt Cu Ni
(m) (m) (m) (ppb) (ppb) (ppb) (ppm) (ppm)
1 9.90 10.15 0.25 762 261 248 10438 37142 10.15 10.45 0.30 823 274 256 8793 46423 10.45 10.75 0.30 904 346 192 11179 50174 10.75 11.00 0.25 1046 309 292 11543 48055 11.00 11.32 0.32 683 210 228 11718 47196 11.32 11.72 0.40 1030 224 268 12323 52707 11.72 12.06 0.34 1226 231 303 14019 41538 12.06 12.54 0.48 1430 288 286 7334 31729 12.54 12.75 0.21 1706 358 330 11788 3640
10 12.75 13.22 0.47 2064 424 336 10898 3426chk 10 12.75 13.22 0.47 1906 319 347avg 10 12.75 13.22 0.47 1985 372 342
11 13.22 13.70 0.48 1953 322 359 7463 303012 13.70 14.00 0.30 1974 317 341 7447 286313 14.00 14.45 0.45 2145 354 359 7533 291814 14.45 14.83 0.38 2163 355 358 8115 311715 14.83 15.27 0.44 2155 341 324 8280 299516 15.27 15.64 0.37 1926 279 0 7043 278317 15.64 15.98 0.34 1904 268 311 6769 251018 15.98 16.38 0.40 2177 331 358 7990 313619 16.38 16.88 0.50 2301 315 375 8359 3506
chk 19 16.38 16.88 0.50 2145 269 344avg 19 16.38 16.88 0.50 2223 292 360
20 16.88 17.41 0.53 2322 557 331 7975 338421 17.41 17.84 0.43 1643 256 288 8118 277422 17.84 18.27 0.43 2012 316 331 7851 291423 18.27 18.67 0.40 2056 314 339 6413 243524 18.67 19.13 0.46 1973 276 317 8127 306225 19.13 19.50 0.37 2159 262 317 7306 271226 19.50 19.76 0.26 2566 236 355 7789 338727 19.76 20.09 0.33 3738 370 493 8763 438228 20.09 20.45 0.36 3522 333 455 8604 471929 20.45 20.86 0.41 2813 259 392 8758 518330 20.86 21.33 0.47 3702 360 508 9147 453931 21.33 21.87 0.54 4557 427 600 10182 482732 21.87 22.16 0.29 3452 255 494 6644 437833 22.16 22.41 0.25 2170 173 332 5410 296434 22.41 22.64 0.23 2350 167 326 6090 292735 22.64 23.09 0.45 2346 198 356 6195 291436 23.09 23.52 0.43 2273 170 324 6113 2668
chk 36 23.09 23.52 0.43 2446 165 320avg 36 23.09 23.52 0.43 2360 168 322
37 23.52 23.91 0.39 1082 80 151 2633 120238 23.91 24.25 0.34 76 0 0 226 10639 24.25 24.75 0.50 46 0 0 154 10740 24.75 25.14 0.39 17 0 0 115 94
APPENDIX 3: (A) Drill Hole Composite - Chiniguchi River Intrusion
JR99-06Sample From To Interval Pd Au Pt Cu Ni
(m) (m) (m) (ppb) (ppb) (ppb) (ppm) (ppm)41 25.14 25.50 0.36 15 0 0 120 8042 25.50 25.68 0.18 15 0 0 42 10143 25.68 25.89 0.21 0 0 0 70 7244 25.89 26.58 0.69 15 0 0 35 9445 26.58 27.13 0.55 0 0 0 110 80
chk 45 26.58 27.13 0.55 11 0 0avg 45 26.58 27.13 0.55 6 0 0
46 27.13 27.74 0.61 11 0 0 89 8047 27.74 28.08 0.34 11 0 0 100 8448 28.08 28.49 0.41 12 0 0 84 6049 28.49 29.00 0.51 38 6 0 76 6850 29.00 29.48 0.48 23 0 0 75 6451 29.48 30.46 0.98 18 0 0 77 6852 30.46 31.42 0.96 20 0 0 79 6353 31.42 32.00 0.58 30 0 17 83 6654 32.00 32.96 0.96 36 0 19 89 6755 32.96 33.87 0.91 22 0 0 76 59
chk 55 32.96 33.87 0.91 15 0 0avg 55 32.96 33.87 0.91 19 0 0
56 33.87 34.25 0.38 15 0 0 22 8057 34.25 34.56 0.31 0 0 0 17 10058 34.56 35.48 0.92 0 0 0 48 9559 35.48 36.36 0.88 0 0 0 69 7960 36.36 37.50 1.14 16 0 0 108 8061 37.50 38.50 1.00 18 0 0 92 72
chk 61 37.50 38.50 1.00 10 0 0avg 61 37.50 38.50 1.00 14 0 0
62 38.50 39.50 1.00 13 0 0 93 7363 39.50 40.50 1.00 16 0 0 92 7364 40.50 41.32 0.82 12 0 0 77 6665 41.32 42.45 1.13 0 0 0 65 8866 42.45 43.14 0.69 0 0 0 115 7367 43.45 44.38 0.93 0 0 0 74 8568 44.38 45.74 1.36 0 0 0 18 9169 46.30 47.00 0.70 0 0 0 11 58
APPENDIX 3: (A) Drill Hole Composite - Chiniguchi River Intrusion
DDH A1-97: J. Rauhala, Waters TownshipTtl Length: 54.25m (178 ft.) - original invoice indicates 178ft hole (May 20-1997)Dip: -45az: 360casing: 2.1m (7 ft.)notes: end of hole is at depth of ~40m (131.4 ft.) verticalnotes: casing still in place; intervals indicate starting point of sampling only
Sample Interval (ft) Interval (m) Description1 7.3 2.23 gabbro2 14 4.27 gabbro3 20 6.10 gabbro4 24 7.32 gabbro5 28 8.53 gabbro6 33 10.06 gabbro7 38 11.58 gabbro8 43 13.11 gabbro9 48 14.63 gabbro
10 54 16.46 gabbro11 58 17.68 gabbro12 63 19.20 gabbro13 67 20.42 gabbro14 71 21.64 gabbro15 78 23.77 gabbro16 83 25.30 gabbro17 85.6 26.09 gabbro18 90 27.43 gabbro19 95 28.96 gabbro20 101 30.78 gabbro21 105.5 32.16 gabbro22 110.5 33.68 gabbro23 115 35.05 gabbro24 119 36.27 gabbro
25a,b,c 122 37.19 start of alteration zone26a 125.7 38.31 alteration zone26b 127 38.71 alteration zone27a 127.8 38.95 alteration zone27b 130 39.62 alteration zone27c 132.5 40.39 alteration zone28 134 40.84 alteration zone29 138 42.06 alteration zone30 143 43.59 blue quartz eyes with ~10% sulphide (max.)31 148.25 45.19 blue quartz eyes with ~10% sulphide (max.)32 153 46.63 blue quartz eyes with ~10% sulphide (max.)33 158 48.16 blue quartz eyes with ~10% sulphide (max.)34 161 49.07 blue quartz eyes with ~10% sulphide (max.)35 168 51.21 biotite alteration with 5-15% diss. sulphide36 171 52.12 biotite alteration with 5-15% diss. sulphide37 177 53.95 biotite alteration with 5-15% diss. sulphide38 178 54.25 biotite alteration with 5-15% diss. sulphide39 179 54.56 biotite alteration with 5-15% diss. sulphide40 180 54.86 biotite alteration with 5-15% diss. sulphide41 180.5 55.02 fg-mg gabbro42 182 55.47 fg-mg gabbro43 183.5 55.93 fg-mg gabbro
APPENDIX 3: (B) Drill Hole A1-97 Makada Lake Intrusion
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)0.
0054
.90
mel
agab
bro
nil
0.00
1.00
1.00
839
2791
870.
71.
0ni
l1.
002.
501.
5014
3327
102
770.
80.
8LA
YER
ED U
NIT
nil
2.50
4.00
1.50
741
2911
611
70.
71.
0ni
l4.
005.
501.
508
4829
112
112
0.6
1.0
(0.0
0 to
89.
5m)
nil
5.50
7.00
1.50
1642
3110
210
30.
71.
0ni
l7.
008.
501.
507
2523
108
960.
90.
9ni
l8.
5010
.00
1.50
953
2610
511
00.
51.
0SU
MM
AR
Yni
l10
.00
12.0
02.
005
1410
105
960.
70.
9LU
: 226
90 to
296
42ni
l12
.00
14.0
02.
006
2719
9085
0.7
0.9
IBZ:
296
43 to
296
83ni
l14
.00
16.0
02.
0010
2922
8810
00.
81.
1B
X: 2
9684
to 2
9753
nil
16.0
018
.00
2.00
737
2310
110
70.
61.
1B
Z: 2
9754
to 2
9759
nil
18.0
020
.00
2.00
830
2279
780.
71.
0FB
X: 2
9760
to 2
9764
nil
20.0
022
.00
2.00
932
1789
970.
51.
1FW
: RV
00-0
1 to
03
nil
22.0
024
.00
2.00
720
1779
940.
91.
2ni
l24
.00
26.0
02.
005
1012
7898
1.2
1.3
nil
26.0
028
.00
2.00
945
2979
830.
61.
1ni
l28
.00
30.0
02.
0010
3633
7610
20.
91.
3ni
l30
.00
32.0
02.
007
3629
8793
0.8
1.1
nil
32.0
034
.00
2.00
731
2310
593
0.7
0.9
nil
34.0
036
.00
2.00
929
3190
961.
11.
1ni
l36
.00
38.0
02.
007
2218
8911
60.
81.
3ni
l38
.00
40.0
02.
007
2319
7795
0.8
1.2
nil
40.0
042
.00
2.00
325
1176
650.
40.
9ni
l42
.00
44.0
02.
005
2413
8111
60.
51.
4ni
l44
.00
46.0
02.
005
2414
7551
0.6
0.7
nil
46.0
048
.00
2.00
616
1272
820.
81.
1ni
l48
.00
49.3
51.
351
228
7647
0.4
0.6
nil
49.3
550
.85
1.50
30
023
220.
9
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86C
olla
r Dip
:
-45
Cas
ing:
1m
NW
D
epth
: 25
9.0m
Grid
Nor
th:
450
[517
2419
.22m
N]
Grid
Eas
t: -3
40[5
5514
6.44
mE]
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)ni
l50
.85
52.0
01.
154
1811
7898
0.6
1.3
nil
52.0
054
.00
2.00
328
1690
101
0.6
1.1
54.9
055
.00
faul
t zon
eni
l54
.00
56.0
02.
003
2011
9191
0.6
1.0
nil
56.0
058
.00
2.00
328
1310
388
0.5
0.9
nil
58.0
060
.00
2.00
30
894
921.
055
.00
89.5
0m
elag
abbr
oni
l60
.00
61.7
51.
7513
5627
138
210.
50.
2ni
l61
.75
62.6
00.
8512
3314
2437
0.4
1.5
LAY
ERED
UN
ITni
l62
.60
64.0
01.
4010
3617
109
670.
50.
6ni
l64
.00
66.1
02.
1010
4024
113
850.
60.
8(0
.00
to 8
9.5m
)ni
l66
.10
67.4
01.
309
4927
172
780.
60.
5tr
67.4
068
.85
1.45
1244
3890
143
0.9
1.6
nil
68.8
570
.20
1.35
1331
3011
310
81.
01.
0ni
l70
.20
72.2
02.
0010
4929
9611
90.
61.
2ni
l72
.20
74.0
01.
8010
3823
107
132
0.6
1.2
nil
74.0
075
.18
1.18
841
1612
056
0.4
0.5
5 C
p75
.18
75.3
00.
1210
5917
279
9590
0.3
34.4
tr75
.30
77.0
01.
7010
2726
112
118
1.0
1.1
nil
77.0
079
.00
2.00
1233
1515
813
40.
50.
8ni
l79
.00
81.0
02.
009
1912
179
830.
60.
52
81.0
081
.40
0.40
1123
1021
216
40.
40.
8tr
81.4
082
.80
1.40
715
1013
699
0.7
0.7
tr82
.80
85.0
02.
2010
3120
9010
80.
61.
2tr
85.0
086
.50
1.50
1144
3310
414
50.
81.
4tr
86.5
088
.00
1.50
1131
2215
511
80.
70.
8tr
88.0
089
.50
1.50
833
2293
113
0.7
1.2
89.5
012
2.30
pegm
atiti
ctr
89.5
091
.00
1.50
924
2057
330.
80.
6le
ucog
abbr
o w
tr
91.0
092
.50
1.50
726
1763
850.
71.
315
% g
abbr
otr
92.5
094
.00
1.50
1220
858
144
412.
80.
9
Grid
Nor
th:
450
[517
2419
.22m
N]
Grid
Eas
t: -3
40[5
5514
6.44
mE]
Col
lar D
ip:
-4
5C
asin
g:
1m N
W
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)IN
CLU
SIO
N -B
EAR
ING
tr94
.00
95.5
01.
506
3021
4144
0.7
1.1
UN
ITtr
95.5
097
.00
1.50
423
1230
970.
53.
2(8
9.5
to 1
60.8
m)
tr97
.00
98.5
01.
504
2414
8546
0.6
0.5
tr98
.50
100.
001.
505
2518
7746
0.7
0.6
89.5
012
2.30
pegm
atiti
ctr
100.
0010
2.00
2.00
515
1565
551.
00.
8(c
ont.)
leuc
ogab
bro
w
tr10
2.00
104.
002.
0012
2817
7812
50.
61.
615
% g
abbr
otr
104.
0010
6.00
2.00
634
1349
540.
41.
1(c
ont.)
tr10
6.00
108.
002.
0011
2413
5087
0.5
1.7
tr10
8.00
110.
002.
005
3313
2748
0.4
1.8
tr11
0.00
112.
002.
006
2411
6340
0.5
0.6
INC
LUSI
ON
-BEA
RIN
Gtr
112.
0011
4.00
2.00
534
1130
550.
31.
8U
NIT
tr11
4.00
116.
002.
003
3119
3147
0.6
1.5
(89.
5 to
160
.8m
)tr
116.
0011
8.00
2.00
630
1830
610.
62.
0tr
118.
0012
0.00
2.00
432
1734
340.
51.
0tr
120.
0012
2.30
2.30
332
2041
340.
60.
8in
crea
sed
PGE
tr12
2.30
124.
001.
709
129
222
6159
1.7
1.0
122.
3013
4.00
gabb
rotr
124.
0012
6.00
2.00
487
8640
361.
00.
9tr
126.
0012
8.00
2.00
972
5928
145
0.8
5.2
INC
LUSI
ON
-BEA
RIN
Gtr
128.
0013
0.00
2.00
984
6332
970.
83.
0U
NIT
tr13
0.00
132.
002.
009
6856
2912
10.
84.
2(8
9.5
to 1
60.8
m)
tr13
2.00
134.
002.
0014
5849
3410
90.
83.
213
4.00
136.
55le
ucog
abbr
oni
l13
4.00
135.
501.
507
8390
1841
1.1
2.3
nil
135.
5013
6.55
1.05
838
6423
551.
72.
413
6.55
148.
00ga
bbro
to m
ela-
tr13
6.55
138.
001.
453
5362
6334
1.2
0.5
gabb
rotr
138.
0014
0.00
2.00
719
819
281
141.
00.
2tr
140.
0014
2.00
2.00
617
025
760
301.
50.
5IN
CLU
SIO
N -B
EAR
ING
tr14
2.00
144.
002.
002
4565
8723
1.4
0.3
UN
ITtr
144.
0014
6.00
2.00
611
013
169
271.
20.
4
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86G
rid N
orth
: 45
0 [5
1724
19.2
2mN
]G
rid E
ast:
-340
[555
146.
44m
E]C
olla
r Dip
:
-45
Cas
ing:
1m
NW
D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)tr
146.
0014
8.00
2.00
510
112
110
911
1.2
0.1
148.
0015
2.90
gabb
rotr
148.
0015
0.00
2.00
1670
6627
740.
92.
7IN
CLU
SIO
N -B
EAR
ING
tr15
0.00
152.
002.
0014
134
130
2796
1.0
3.6
UN
ITtr
152.
0015
2.90
0.90
1011
810
530
530.
91.
8(8
9.5
to 1
60.8
m)
152.
9015
4.00
gran
ite d
yke
tr15
2.90
154.
001.
109
3217
1582
0.5
5.5
tr15
4.00
155.
501.
5038
125
109
3257
0.9
1.8
tr15
5.50
157.
001.
507
8962
3242
0.7
1.3
154.
0016
0.80
gabb
rotr
157.
0015
8.50
1.50
2728
752
026
116
1.8
4.5
tr15
8.50
160.
001.
5012
153
202
2549
1.3
2.0
tr16
0.00
160.
800.
8034
206
331
1949
1.6
2.6
160.
8022
9.70
gabb
ro b
recc
ia0.
516
0.80
161.
801.
0026
7610
848
305
1.4
6.4
<0.5
161.
8016
2.50
0.70
5230
460
062
335
2.0
5.4
BR
ECC
IA U
NIT
<116
2.50
163.
000.
5030
124
144
7341
41.
25.
7tr
163.
0016
5.00
2.00
3715
627
328
621.
82.
2(1
60.8
to 2
25.7
m)
tr16
5.00
166.
651.
6528
8013
914
136
81.
72.
6<0
.516
6.65
167.
500.
8519
7420
468
262
2.8
3.9
tr16
7.50
168.
501.
0023
9312
255
243
1.3
4.4
<0.5
168.
5017
0.15
1.65
768
9444
283
1.4
6.4
<0.5
170.
1517
1.15
1.00
3614
128
934
274
2.0
8.1
<0.5
171.
1517
2.00
0.85
2794
225
4720
32.
44.
3<0
.517
2.00
173.
001.
0013
5387
5857
1.6
1.0
<0.5
173.
0017
3.50
0.50
4516
639
112
355
32.
44.
5<0
.517
3.50
175.
001.
5011
955
311
7340
156
1220
2.1
7.8
<117
5.00
176.
251.
2576
359
818
2213
273
52.
35.
6<0
.517
6.25
177.
751.
5057
162
269
1012
378
31.
76.
4tr
177.
7517
9.40
1.65
5214
322
40
145
719
1.6
5.0
<0.5
179.
4017
9.90
0.50
138
672
1750
4327
616
902.
66.
1
Grid
Nor
th:
450
[517
2419
.22m
N]
Grid
Eas
t: -3
40[5
5514
6.44
mE]
Col
lar D
ip:
-4
5C
asin
g:
1m N
W
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)1-
217
9.90
181.
001.
1024
716
1348
3410
749
123
103.
04.
716
0.80
229.
70ga
bbro
bre
ccia
2-3
181.
0018
1.85
0.85
443
2310
6600
178
532
3600
2.9
6.8
(con
t.)(c
ont.)
3-4
181.
8518
2.90
1.05
345
1510
4915
117
330
2770
3.3
8.4
<0.5
182.
9018
4.40
1.50
1770
666
2514
90.
96.
0B
REC
CIA
UN
IT2
184.
4018
4.60
0.20
323
576
1958
1619
522
903.
411
.7tr
184.
6018
5.05
0.45
6639
611
3123
107
607
2.9
5.7
(160
.8 to
225
.7m
)2
185.
0518
5.65
0.60
151
1639
3400
7210
862
12.
15.
8<1
185.
6518
6.40
0.75
9855
213
8740
161
1080
2.5
6.7
<0.5
186.
4018
7.00
0.60
5025
667
414
7838
82.
65.
01-
218
7.00
187.
450.
4513
070
921
7353
230
1460
3.1
6.3
<118
7.45
188.
300.
8510
542
211
3331
166
1300
2.7
7.8
<0.5
188.
3019
0.00
1.70
2517
240
010
109
162
2.3
1.5
219
0.00
190.
500.
5018
489
530
0171
260
1890
3.4
7.3
<0.5
190.
5019
1.30
0.80
4020
651
615
116
395
2.5
3.4
119
1.30
191.
650.
3514
312
1231
6099
435
1650
2.6
3.8
<0.5
191.
6519
3.00
1.35
2613
833
07
9528
52.
43.
0<0
.519
3.00
193.
700.
7075
436
1112
3217
282
52.
64.
81-
1.5
193.
7019
4.50
0.80
128
653
1583
4439
418
502.
44.
7<1
194.
5019
6.00
1.50
9442
911
7831
196
1140
2.7
5.8
219
6.00
197.
151.
1515
282
627
1957
372
2180
3.3
5.9
0.5
197.
1519
8.55
1.40
7132
893
722
383
2240
2.9
5.8
tr19
8.55
199.
300.
7513
5090
023
151
1.8
6.6
0.5
199.
3020
0.00
0.70
4760
122
0399
247
805
3.7
3.3
120
0.00
201.
001.
0012
949
416
4846
285
1700
3.3
6.0
<120
1.00
202.
001.
0016
095
936
0380
356
2090
3.8
5.9
<120
2.00
202.
800.
8026
610
4439
7697
442
3550
3.8
8.0
3-5
202.
8020
3.05
0.25
315
2001
9140
159
696
4940
4.6
7.1
320
3.05
203.
550.
5030
787
932
5172
386
3400
3.7
8.8
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86G
rid N
orth
: 45
0 [5
1724
19.2
2mN
]G
rid E
ast:
-340
[555
146.
44m
E]C
olla
r Dip
:
-45
Cas
ing:
1m
NW
D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)<0
.520
3.55
204.
100.
5550
195
627
2096
677
3.2
7.1
<0.5
204.
1020
5.30
1.20
2917
543
115
102
320
2.5
3.1
<120
5.30
206.
351.
0533
162
438
1310
950
52.
74.
63-
520
6.35
207.
050.
7011
255
715
2539
414
1930
2.7
4.7
160.
8022
9.70
gabb
ro b
recc
ia<1
207.
0520
7.75
0.70
6333
994
328
328
1130
2.8
3.4
(con
t.)(c
ont.)
<0.5
207.
7520
8.75
1.00
4351
616
0942
258
433
3.1
1.7
1-2
208.
7520
9.65
0.90
121
865
2661
8443
916
803.
13.
80.
520
9.65
210.
200.
5585
604
1889
4825
910
803.
14.
2B
REC
CIA
UN
IT<1
210.
2021
1.00
0.80
7733
712
4733
244
1200
3.7
4.9
<121
1.00
211.
600.
6011
959
818
2649
324
1410
3.1
4.4
(160
.8 to
225
.7m
)<0
.521
1.60
212.
500.
9059
218
492
1511
174
52.
36.
7<1
212.
5021
3.10
0.60
7148
913
0047
312
1010
2.7
3.2
621
3.10
213.
500.
4012
364
518
3650
530
2210
2.8
4.2
121
3.50
214.
150.
6510
639
811
2433
442
1630
2.8
3.7
<121
4.15
215.
301.
1586
303
824
2336
510
202.
72.
8<0
.521
5.30
216.
801.
5016
166
512
1310
915
13.
11.
4<1
216.
8021
7.60
0.80
9963
417
1753
320
1400
2.7
4.4
<0.5
217.
6021
9.00
1.40
3529
385
937
185
597
2.9
3.2
121
9.00
220.
001.
0010
958
617
9851
258
1250
3.1
4.8
122
0.00
220.
850.
8575
401
1054
3124
310
502.
64.
3<0
.522
0.85
221.
400.
5563
581
1708
4931
110
902.
93.
51-
222
1.40
222.
300.
9016
074
221
0455
502
2090
2.8
4.2
tr22
2.30
223.
000.
7065
370
1162
2825
911
903.
14.
6<0
.522
3.00
224.
501.
5024
102
194
142
392
1.9
2.8
tr22
4.50
225.
701.
2026
115
309
119
357
2.7
3.0
BO
UN
DA
RY
UN
IT<0
.522
5.70
227.
251.
5540
171
373
151
743
2.2
4.9
tr22
7.25
229.
001.
7521
6511
088
414
1.7
4.7
(225
.7 to
233
.2m
)tr
229.
0022
9.70
0.70
2679
191
9447
62.
45.
1
Grid
Nor
th:
450
[517
2419
.22m
N]
Grid
Eas
t: -3
40[5
5514
6.44
mE]
Col
lar D
ip:
-4
5C
asin
g:
1m N
W
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
From
ToR
ock
Type
%V
SFr
omTo
Inte
rval
Au
PtPd
Rh
Ni
Cu
Pd:P
tC
u:N
i(m
)(m
)(U
nit)
(max
)(m
)(m
)(m
)(p
pb)
(ppb
)(p
pb)
(ppb
)(p
pm)
(ppm
)22
9.70
259.
00sh
eare
d tr
229.
7023
1.00
1.30
1245
6814
716
41.
51.
1ga
bbro
(?) f
ootw
all
tr23
1.00
232.
001.
0017
5617
517
614
53.
10.
8tr
232.
0023
3.20
1.20
940
7016
384
1.8
0.5
FOO
TWA
LL B
REC
CIA
tr23
3.20
235.
001.
8020
1519
144
901.
30.
6tr
235.
0023
6.50
1.50
1324
1917
011
40.
80.
7(2
33.2
to 2
48.0
m)
tr23
6.50
238.
001.
507
2114
123
960.
70.
8tr
238.
0023
9.50
1.50
2228
1613
789
0.6
0.6
tr23
9.50
241.
502.
0017
015
148
600.
4
2% p
y24
4.00
244.
300.
30
FOO
TWA
LL
(248
.0 to
259
.0m
)10
% p
y25
0.00
250.
260.
265%
py
255.
7825
6.00
0.22
Col
lar D
ip:
-4
5C
asin
g:
1m N
W
Hol
e N
o.:
RV
00-2
2C
olla
r Bea
ring:
86D
epth
: 25
9.0m
Elev
atio
n: +
325.
24m
MSL
Grid
Nor
th:
450
[517
2419
.22m
N]
Grid
Eas
t: -3
40[5
5514
6.44
mE]
APP
END
IX 3
: (C
) Dril
l Hol
e R
V00
-22
Riv
er V
alle
y In
trusi
on
572
VITA Name: Laurence Scott Jobin-Bevans Post-secondary The University of Manitoba Education and Winnipeg, Manitoba, Canada Degrees: 1991-1995 B.Sc.(hons) The University of Manitoba Winnipeg, Manitoba, Canada 1995-1997 M.Sc. Honours and Paul R. Beaudoin Memorial Geochemistry Scholarship Awards: 1993
Mark G. Smerchanski Memorial Prize 1994 Dr. George Brownell Memorial Prize 1994 NSERC Postgraduate Scholarship (M.Sc.) 1995-1997 C.K. Bell Memorial Research Prize 1996 The University of Western Ontario, Graduate Tuition Scholarship 1997-1999 CIM Graduate Thesis Award (M.Sc.) 1998 NSERC Postgraduate Scholarship (Ph.D.) 1997-1999 Hugh E. McKinstry Fund Scholarship 1998 Province of Ontario Graduate Scholarship 1999-2001
Related Work Teaching Assistant Experience: The University of Western Ontario 1997-1998 Projects Manager Pacific North West Capital Corp. 1999-2004 Publications: Easton, R.M., Jobin-Bevans, L.S. and James, R.S., 2004. Geological Guidebook to the Paleoproterozoic East Bull Lake Intrusive Suite Plutons at East Bull Lake, Agnew Lake and River Valley, Ontario. Ontario Geological Survey, Open File Report 6135, 84 pp.
573
James, R.S., Jobin-Bevans, S., Easton, R.M., Wood, P., Hrominchuk, Keays, R.R. and Peck, D.C., 2002. Platinum-group element mineralization in Paleoproterozoic basic intrusions in Central and northeastern Ontario, Canada. In: The Geology, Geochemistry, Mineralogy and Mineral Beneficiation of Platinum-Group Elements. Edited by L.J. Cabri. Canadian Institute of Mining, Metallurgy and Petroleum, Special Volume 54, p. 339-365. Jobin-Bevans, L.S., Keays, R.R. and MacRae, N.D., 1999. Project 97012. Cu-Ni-PGE in Nipissing Diabase: Results from surface and core samples. In: Summary of Field Work and Other Activities, 1999. Ontario Geological Survey, Open File Report 6000, p. 33-1-33-5. Jobin-Bevans, L.S., MacRae, N.D. and Keays, R.R., 1998. Cu-Ni-PGE Potential of the Nipissing Diabase. In: Summary of Field Work and Other Activities. Ontario Geological Survey, Miscellaneous Paper 169, p. 220-223.
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