geotectonics in the gawler craton: constraints from ... · geotectonics in the gawler craton:...
TRANSCRIPT
Geotectonics in the Gawler Craton: Constraints from geochemistry, U-Pb
geochronology and Sm-Nd and Lu-Hf isotopes
Katherine E. Howard
Geology and GeophysicsSchool of Earth and Environmental Sciences
The University of Adelaide
October 2011
-i-
Table of Contents
Abstract v
Declarati on vii
Journal Arti cles viii
Conference Abstracts ix
Statement of Authorship x
Acknowledgements xiii
Chapter 1 - Introducti on, Geotectonics in the Gawler Craton
Project Overview 3Thesis Outline 7
Chapter 2 – Detrital zircon ages: Improving interpretati on via Nd and Hf isotopic data
Introducti on 15Geological setti ng 16
West of the Kalinjala Shear Zone 16East of the Kalinjala Shear Zone 16
Analyti cal Methods 16U–Pb zircon dati ng 16Whole–rock Sm–Nd isotopic analyses 18Zircon Hf isotopic analyses 18
Results 19LA–ICP–MS U–Pb detrital zircon data from the Corny Point Paragneiss 19LA–ICP–MS U–Pb zircon data from Gawler Craton samples 19Sm–Nd isotopic results 21Zircon Hf isotopic results 21
Discussion 21Corny Point Paragneiss – depositi onal age constraints 21Correlati on of detrital zircon ages with a potenti al source region 21Correlati on of isotopic data with a potenti al source region 22Other potenti al source regions for the Corny Point Paragneiss Protoliths 24Limitati ons of provenance as a palaeogeographic tool 26
Conclusion 28References 28Supplementary Material 30
Chapter 3 – U–Pb, Lu–Hf and Sm–Nd isotopic constraints on provenance and depositi onal ti m-ing of metasedimentary rocks in the western Gawler Craton: Implicati ons for Proterozoic recon-structi on models
Introducti on 53Geological background 55Samples and analyti cal methods 56
Whole rock geochemistry 56
-ii-
U–Pb zircon and monazite dati ng 57Zircon Hf isotopic analyses 57Whole rock Sm–Nd isotopic analyses 58
Results 58Major and trace element geochemistry of metasedimentary rocks 58Sm–Nd systemati cs 60U–Pb zircon geochonology 60Zircon Hf isotopic results 61U–Pb monazite geochronology 61
Discussion 61Depositi onal age constraints 61Source characteristi cs of the Fowler Domain metasedimentary rocks 62Correlati ons with other basin systems within the southern Australia Proterzoic 64Provenance implicati ons for reconstructi on models of Proterozoic Australia 69
Conclusions 70References 70Supplementary Material 73
Chapter 4 – Provenance of late Paleoproterozoic cover sequences in the central Gawler Cra-ton: exploring strati graphic correlati ons in eastern Proterozoic Australia using detrital zircon ages, Hf and Nd isotopic data
Introducti on 89Geological background 90Analyti cal methods 94
Whole–rock geochemistry 94U–Pb zircon dati ng 94Whole rock Sm–Nd isotopic analyses 96Zircon Hf isotopic analyses 96
Results 96Geochemistry 96U–Pb zircon geochronology 97Whole–rock Sm–Nd analyses 102Zircon Hf isotopic results 102
Discussion 104Depositi onal ti ming and source characteristi cs 104Provenance correlati ons and tectonic implicati ons 106
Conclusions 111References 112Supplementary Material 115
Chapter 5 – U–Pb zircon, zircon Hf and whole–rock Sm–Nd isotopic constraints on the evolu-ti on of Paleoproterozoic rocks in the northern Gawler Craton
Introducti on 137Geological Setti ng 137
Geology of the northern Gawler Craton 139Analyti cal methods 140Results 142
U–Pb zircon geochronology 142
-iii-
U–Pb monazite geochronology 146Interpretati on of protoliths 146Geochemistry 146Lu–Hf isotopic data for zircon grains 150Whole rock Sm–Nd isotopic data 150
Discussion 150Geochronology & isotopic compositi ons of orthogneisses in the nthn Gawler Craton 150Similariti es to Aileron Region of North Australian Craton 153Implicati ons for provenance of metasedimentary rocks in the Gawler Craton 156Implicati ons for provenance of modern day sediments from the Gawler Craton 158
Conclusions 158References 158Supplementary Material 161
Chapter 6 – Laurenti a and Australia share a widespread 1.45 Ga event within the Rodinian superconti nent
Introducti on 173The 1.45 Ga record in Australia 174Proposed conti nental confi gurati on at 1.45 Ga 178Conclusions 181References 181Supplementary Material 183
Chapter 7 – Conclusions 197
Implicati ons for reconstructi on models including Proterozoic Australia 199
-v-
Abstract
The southern Australian Mesoarchean to early Mesoproterozoic Gawler Craton holds a pivotal place in the architecture of Proterozoic Australia. Although in recent years a growing body of work has signifi cantly improved our understanding of the tectonic evoluti on of the Gawler Craton, the lack of outcrop across large areas is an impediment to determining the tectonic framework. This study uses geochemical, geochronological (U-Pb zircon and monazite) and isotopic (Whole rock Sm-Nd and zircon Lu-Hf) data on samples mostly obtained from drill holes in regions of limited to non-existent outcrop to bett er delineate the tectonic setti ng of Proterozoic metasedimentary and igneous units in the western, central and northern Gawler Craton and the orogenic events which have aff ected them.
It is common practi ce in sedimentary provenance studies to use similariti es in the detrital zircon age histograms from sedimentary systems to identi fy potenti al source regions, and therefore to make interpretati ons about paleogeographic setti ngs. However, this method is limiti ng as the ti ming of zircon growth events is not a unique criterion of specifi c terrains. Nevertheless, these limitati ons can be overcome by employing additi onal isotopic data sets such as Sm - Nd and Lu - Hf that provide informati on on the crustal evoluti on of the source region. As an example, the age spectra of detrital zircons in Paleoproterozoic metasedimentary rocks in the eastern Gawler Craton in southern Australia are virtually identi cal to the dominant zircon growth ti melines in adjacent older domains of the Gawler Craton, suggesti ng that it was the source region. However, the combinati on of bulk rock Nd and Hf zircon data suggest that the Gawler Craton is not a viable source region for the metasedimentary packages, despite the striking similarity between detrital zircon ages and zircon crystallisati on events within the craton.
The western Gawler Craton occupies a key positi on in a number of Paleoproterozoic reconstructi on models of Australia. Zircon and monazite U-Pb data obtained from drill holes in the Fowler Domain show that sedimentati on occurred over the interval 1760 – 1700 Ma, closely followed by upper amphibolite to granulite-grade metamorphism and deformati on in the interval 1690 – 1670 Ma. The ti ming of tectonism is synchronous with the Kimban Orogeny, which shaped the tectonic architecture in the eastern Gawler Craton. Detrital zircon ages indicate that sediment source regions for the metasedimentary rocks from the Fowler Domain are similar to other Paleoproterozoic basin systems in the northern and eastern Gawler Craton, suggesti ng the former existence of a large 1760 – 1700 Ma depositi onal system across what is now the South Australian Craton. Rather than a source dominated by Archean to early Paleoproterozoic rocks of the Gawler Craton, the source characteristi cs (age and isotopic compositi on) of the Paleoproterozoic basin system favour the North Australian Craton as a source. This suggests that the Gawler Craton and the North Australian Craton may have been part of a single lithospheric domain at around 1750-1700 Ma.
Data obtained from outcropping sedimentary sequences in the central craton indicate that the Gawler Craton shares basin formati on ti me lines with the adjacent Curnamona Province, suggesti ng that they comprise a single lithospheric domain at the ti me of depositi on. Detrital U-Pb zircon ages from the 1715 Ma Labyrinth Formati on show similariti es with 1760 – 1700 Ma basin systems in the western and northern Gawler Craton as well as the Curnamona Province, however, the Labyrinth Formati on contains an isotopically evolved component consistent with input from the underlying Archean rocks in the central Gawler Craton. The overlying 1650 Ma Tarcoola Formati on is isotopically more juvenile, and cannot simply be derived from erosion of the underlying sequences. Both the ti ming of basin development and the juvenile nature of the Tarcoola Formati on is similar to units in the Curnamona Province as well as in northeastern Australia. This may suggest the presence of a large scale ca 1650 Ma juvenile basin system across eastern Proterozoic Australia.
U-Pb geochronology of orthogneisses intersected in drill holes in the unexposed northern Gawler Craton constrain the ti ming of magmati sm to ca 1780 – 1750 Ma. These graniti c rocks form basement to sedimentary successions that were deposited between ca 1740-1720 Ma, which have minimum depositi onal ages constrained by regional medium to high-grade metamorphism at ca 1730-1700 Ma, coincident with the Kimban Orogeny. The ti ming of magmati sm and subsequent sedimentati on and metamorphism is similar to that in the Arunta region of the southern North Australian Craton. This supports provenance links from metasedimentary units from the Fowler Domain of the western Gawler Craton with the Arunta region, and strengthens the paleogeographic connecti on between these two regions at ca 1780-1700 Ma.
Monazite geochronology from three drill holes in the northern Gawler Craton has revealed ca 1450 Ma ti ming for magmati sm and high grade metamorphism. Elsewhere in the Gawler Craton this age corresponds to reacti vati on and cooling of crustal shear zones, as well as regional resetti ng of Rb-Sr isotopic systems. The sparse record of drill holes in the western Gawler Craton also intersect a pegmati te of this age as well as graniti c rocks, suggesti ng the ca 1450 Ma thermal record may be more widespread than appreciated. Across Proterozoic Australia there is a diff use but widespread record of ca 1450 Ma events that encompass graniti c magmati sm, regional cooling, isotopic resetti ng and basin development. The spati al scale of this record suggests it formed part of a larger system at that ti me which would have connected with eastern Proterozoic Australia. The most plausible paleogeographic connecti on is with southern and western Laurenti a, which contains an extensive province characterised by felsic magmati sm, localised deformati on and regional cooling and isotopic resetti ng. In this case the ca 1450 Ma record in Australia provides an important paleogeographic constraint for Mesoproterozoic conti nental confi gurati ons.
-vii-
Declarati on
This work contains no material which has been accepted for the award of any other degree or di-ploma in any university or other terti ary insti tuti on to Katherine E. Howard and, to the best of my knowledge and belief, contains no material previously published or writt en by another person, except where due reference has been made in the text.
I give consent to this copy of my thesis when deposited in the University Library, being made available for loan and photocopying, subject to the provisions of the Copyright Act 1968.
The author acknowledges that copyright of published works contained within this thesis (as listed under Publicati ons) resides with the copyright holders of those works.
I also give permission for the digital version of my thesis to be made available on the web, via the University’s digital research repository, the Library catalogue, the Australasian Digital Theses Program (ADTP) and also through web search engines, unless permission has been granted by the University to restrict access for a period of ti me.
Katherine E. Howard
-viii-
Journal Arti cles
Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Cutt s, K.A., Belousova, E.A., 2011. U-Pb zir-con, zircon Hf and whole-rock Sm-Nd isotopic constraints on the evoluti on of Paleoproterozoic rocks in the northern Gawler Craton. Australian Journal of Earth Sciences 58, 615-638.
Howard, K.E., Hand, M., Barovich, K.M., Belousova, E.A., 2011. Provenance of late Paleoprotero-zoic cover sequences in the central Gawler Craton: exploring strati graphic correlati ons in eastern Proterozoic Australia using detrital zircon ages, Hf and Nd isotopic data. Australian Journal of Earth Sciences, 58, 475-500.
Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Belousova, E.A., 2011. U-Pb, Lu-Hf and depo-siti onal ti ming of metasedimentary rocks in the western Gawler Craton: Implicati ons for Protero-zoic reconstructi on models. Precambrian Research 184, 43-62.
Shufeldt, O.P., Karlstrom, K.E., Gehrels, G.E., Howard, K.E., 2010. Archean detrital zircons in the Proterozoic Vishnu Schist of the Grand Canyon, Arizona: Implicati ons for crustal architecture and Nuna superconti nent reconstructi ons. Geology 38, 1099-1102.
Reid, A., Flint, R., Maas, R., Howard, K.E., Belousova, E.A., 2009. Geochronological and isotopic constraints on Palaeoproterozoic skarn base metal mineralisati on in the central Gawler Craton, South Australia. Ore Geology Reviews 36, 350-362.
Howard, K.E., Hand, M., Barovich, K., Reid, A., Wade, B.P., Belousova, E.A., 2009. Detrital zircon ages: Improving interpretati on via Nd and Hf isotopic data. Chemical Geology 262, 277-292.
Howard, K.E., Reid, A.J., Hand, M., Barovich, K., Belousova, E.A., 2007. Does the Kalinjala Shear Zone represent a palaeosuture zone? Implicati ons for distributi on of styles of Mesoproterozoic mineralisati on in the Gawler Craton. MESA Journal 43, 16-20.
-ix-
Conference Abstracts
Howard, K.E., Hand, M., Barovich, K., Lambeck, A., Belousova, E. A., 2010. Provenance of late Palaeoproterozoic cover sequences in the central eastern Gawler Craton: Exploring strati graphic correlati ons with Curnamona and Mt Isa using detrital zircon, zircon Hf and Nd isotopic data. In: Quinn, C.D. & Daczko, N.R. (eds.) Abstracts of the Specialist Group in Tectonics and Structural Ge-ology Conference, Port Macquarie. Geological Society of Australia Abstracts 97, 36.
Howard, K.E., Hand, M., Barovich, K., Belousova, E. A., 2010. Provenance of metasedimentary rocks in the western Gawler Craton: Geochemical, zircon U-Pb, Lu-Hf and whole rock Sm-Nd iso-topic constraints. In: Quinn, C.D. & Daczko, N.R. (eds.) Abstracts of the Specialist Group in Tecton-ics and Structural Geology Conference, Port Macquarie. Geological Society of Australia Abstracts 97, 35
Howard, K.E., Hand, M., Barovich, K., Payne, J.L., Belousova, E.A., 2010. U-Pb zircon, zircon Hf and whole rock Sm-Nd isotopic constraints on the evoluti on of Palaeoproterozoic rocks in the northern Gawler Craton. In: Quinn, C.D. & Daczko, N.R. (eds.) Abstracts of the Specialist Group in Tectonics and Structural Geology Conference, Port Macquarie. Geological Society of Australia Abstracts 97, 37.
Howard, K.E., Hand, M., Barovich, K., Szpunar, M., Payne, J. L., 2009. Nd isotopic constraints on the provenance of cover sequences in the southern Australian Proterozoic. 2009 Joint Assembly, The Meeti ng of the Americas, Toronto, Canada.
Howard, K.E., Hand M., Barovich, K., Belousova, E.A., Wade, B.P., 2008. U-Pb, Nd and Hf isotopic constraints on basin development and deformati on in the Western Gawler Craton. Australian Earth Sciences Conventi on, Perth, 2008. Geological Society of Australia and the Australian Insti -tute of Geoscienti sts, volume 19.
Howard, K.E., Hand, M., Barovich, K., Reid, A., Belousova, E.A., 2007. Limitati ons of the age-only approach to zircon provenance studies: The applicati on of whole-rock Nd and zircon Hf isotopic data. In A.S. Collins (editor), SGTSG 2007 Deformati on in the Desert. Geological Society of Aus-tralia, Alice Springs.
-x-
Statement of Authorship
Much of the research presented in this thesis has been published in scienti fi c journals. Biblio-graphic details are listed at the beginning of each chapter. The contributi on of each author is described below.
HOWARD, K.E. (Candidate)Chapters 2-5: Project design, fi eldwork/sampling, sample preparati on, data collecti on, data pro-cessing, data interpretati on, manuscript design and compositi on, generati on of fi gures and tables.I certi fy that the above statement is accurate.
Signed Date
HAND, M. & BAROVICH, K. (Supervisors)Chapters 2-5: Project design, fi eldwork, guidance with data interpretati on, manuscript review.I certi fy that the above statement is accurate, and I give permission for the relevant manuscripts to be included in this thesis.
Signed Date
Signed Date
BELOUSOVA, E.A., (External Supervisor)Chapters 2-5: Assistance with multi collector ICP-MS and data interpretati on, manuscript review.I certi fy that the above statement is accurate, and I give permission for the relevant manuscripts to be included in this thesis.
Signed Date
-xi-
REID, A. & WADE, B.P.Chapter 2: Assistance with sample preparati on, data interpretati on, manuscript review.I certi fy that the above statement is accurate, and I give permission for the relevant manuscripts to be included in this thesis.
Signed Date
Signed Date
PAYNE, J.L.Chapters 3 & 5: Assistance with sample preparati on, data interpretati on, manuscript review.I certi fy that the above statement is accurate, and I give permission for the relevant manuscripts to be included in this thesis.
Signed Date
CUTTS, K.A.Chapter 5: Assistance with sample preparati on, data interpretati on, manuscript review.I certi fy that the above statement is accurate, and I give permission for the relevant manuscripts to be included in this thesis.
Signed Date
-xiii-
Acknowledgements
Firstly, I would like to thank my amazing supervisors Marti n Hand, Karin Barovich and Elena Belousova for all the help and guidance they have given me over the years. Elena has been a fantasti c help with the multi -collector and interpreti ng the Hf data. Karin has been an inspirati onal role model, and being a realist, has always managed to keep the project from expanding out of control. I am greatly indebted to Marty, who has been an excellent primary supervisor and has always managed to bring out the best in me.
A big thanks also goes to Justi n Payne for reading through all my draft s, giving me a pat on the back when I needed it, and also being a good friend.
The staff at Adelaide Microscopy, especially Angus Netti ng and Ben Wade, have off ered invaluable technical assistance with the LA-ICP-MS and SEM faciliti es. It should also be noted that without the well stocked biscuit barrel and Milo ti n at Adelaide Microscopy, the quality of the data presented in this thesis could not have been achieved. I’d also like to acknowledge GEMOC for allowing me access to their multi -collector faciliti es and in parti cular Norm Pearson, Elena Belousova and Justi n Payne for providing technical assistance. Thanks also go to David Bruce from the University of Adelaide, for all his help with the Nd data acquisiti on.
I’d also like to acknowledge the assistance given by the team at the Geological Survey, especially former staff member Sue Daly, for sharing ideas and resources with me. I’d also like to thank the team at the Core Library for all their assistance. Special thanks goes to Anthony Reid for being an unoffi cial supervisor from ti me to ti me, for reading through draft s and for cheering me on as I got closer to the end.
I would also like to thank Geoff Fraser, William Griffi n, Russell Korsch, Roland Maas, Oliver Nebel, Jonathan Patchett , Roberta Rudnick, Catherine Spaggiari, and two anonymous reviewers for their constructi ve and helpful reviews which have greatly improved the various chapters of this thesis.
Thanks go to all the University of Adelaide friends I’ve made along the way, including Kathryn, Diana, Ailsa, Spuz, Rachel, Yee, Tom, Ben, Udeni, Kate, Dave, Graham, Forbes, Russell, Jade, Frank, Alec and Deborah. I’d also like to acknowledge the support from the Honours crew of 2011.
This thesis would not have been possible without the love and support of my friends and family. In parti cular, Mum, Dad, Erin, Simon, Siân and Chris. You guys are amazing. This thesis is dedicated to you!
Lastly, a special thanks to Vinnie. You have kept me sane throughout this whole process. You’ve been everything from a house-wife to a journal editor when I needed it of you. Thank you.
Chapter 1
-3-
Introducti on
Project Overview
The Gawler Craton forms a crystalline basement which occupies approximately 440,000 km2 beneath central South Australia. It consists of a Meso- to Neo- Archean basement, which is intruded and overlain by younger Paleoproterozoic and Mesoproterozoic igneous and sedimentary rocks (Daly et al. 1998, Hand et al. 2007). It is positi oned within the South Australian Craton, which along with the North and West Australian Cratons, form Proterozoic Australia (Figure 1). It is considered highly prospecti ve for mineral explorati on as it hosts Olympic Dam, a world class Iron-Oxide-Copper-Gold-Uranium deposit, and a number of smaller although sti ll signifi cant deposits. In recent years, extensive work has been undertaken to improve our understanding of the tectonic evoluti on of the Gawler Craton (e.g. Fanning et al. 2007, Hand et al. 2007, Fraser et al. 2010).
The oldest rocks in the Gawler Craton are the recently discovered Mesoarchean 3150 Ma gneissic granites outcropping in the south-eastern Gawler Craton (Fraser et al. 2010). The late Archean Gawler Craton consists of metasedimentary, metavolcanics and granite-greenstone units located in two separate domains that are thought to be equivalent on the basis of geochemical, isotopic and geochronological data (Swain et al. 2005a, Hand et al. 2007). The Mulgathing Complex is located in the central Gawler Craton and consists of the Christi e Gneiss, the Kenella Paragneiss, the Harris Greenstone Belt, the Devil’s Playground Volcanics and the ca 2500 Ma Glenloth Granite. The Sleaford Complex is located in the south of the craton and consists of the metasedimentary Carnot Gneiss and Wangary Paragneiss, the Hall Bay Volcanics and the intrusive Dutt on Suite. Metamorphism associated with the Sleaford Orogeny took place between 2480 and 2420 Ma and ranges in grade between greenschist and granulite
facies (Daly et al. 1998, McFarlane 2006). There was also a period of granite emplacement at ca 2440 Ma (Daly et al. 1998).
Aft er a period of apparent tectonic stability from ca 2400 to 2000 Ma, the precursor to the granodioriti c Miltalie Gneiss intruded at ca 2000 Ma in the eastern Gawler Craton (Fanning et al. 2007). Sequences of the Darke Peak Group (formerly included in the Hutchison Group) are interleaved with 1866 ± 10 Ma felsic volcanic rocks (Rankin et al. 1988, Daly et al. 1998, Fanning et al. 2007, Szpunar et al. 2011) and overly the ca 2000 Ma Miltalie Gneiss. The emplacement of the voluminous Donington Suite at 1850 Ma was synchronous with the Cornian Orogeny (Reid et al. 2008) and was followed by a period of widespread sedimentati on and volcanism (Daly et al. 1998, Hand et al. 2007). This includes the 1791 ± 4 Ma Myola Volcanics (Fanning et al. 1988), 1774 ± 16 Ma volcanics and associated sedimentary rocks of the Peake and Denison Inlier (Fanning et al. 2007) and the 1767 ± 17 Ma Price Metasediments (Oliver & Fanning 1997). More widespread depositi on conti nued between 1760 and 1700 Ma. The Wallaroo Group was deposited between ca 1760 and 1740 Ma (Fanning et al. 2007). Similarly the Cleve Group (formerly included in the Hutchison Group) was deposited between 1780 – 1730 Ma (Szpunar et al. 2011). Toward the north of the craton, protoliths to metasedimentary rocks were deposited at ca 1750 Ma in the Mt Woods Domain (Chalmers 2007, Jagodzinski et al. 2007) and at ca 1740–1720 Ma in the northern Gawler Craton (Payne et al. 2006). A short widespread pulse of magmati sm at 1730 Ma (Hopper 2001, Fanning et al. 2007, Hand et al. 2007) was followed by the 1730–1690 Ma Kimban Orogeny (Hand et al. 2007, Payne et al. 2008, Dutch et al. 2010). This was an extensive craton-wide event which coincided with the terminati on of widespread depositi on (Hand et al. 2007, Payne et al. 2009). Metamorphism
-4-
Chapter 1 Introducti on
Figure 1. Simplifi ed solid geology of the Gawler Craton (aft er Payne et al., 2006). Inset: simplifi ed map of Proterozoic Australia (aft er Myers et al. 1996; Wade et al. 2006), CP = Curnamona Province, GC = Gawler Craton.
Blue Range beds
Spilsby Suite (ca 1500 Ma)
Munjeela Granite (ca 1580 Ma)
Hiltaba Suite (1590-1575 Ma)
Gawler Range Volcanics (1590 Ma)
St Peter Suite and Nuyts Volcanics (1640-1620 Ma)
Middlecamp, Moody & Tunkillia (ca 1730, 1700 & 1690-1670 Ma)
Undifferentiated Fowler Domain
Undifferentiated Nawa Domain
Price, Moonta, Wallaroo, McGregor & Myola (ca 1780-1740 Ma)
Undifferentiated Coober Pedy and Mt Woods Domains
Undifferentiated Peake and Denison Inliers (ca 1800-1720 & 1550 Ma)
Donington Suite (ca 1850 Ma)
Former Hutchison Group: (ca 1865 Ma Darke & Peake, 1780 - 1720 Ma Cleve)
Undifferentiated Miltalie Ortho-, Para-Gneiss (ca 2000 Ma)
Archean Mulgathing and Sleaford Complexes
Arc
hean
P
aleo
prot
eroz
oic
M
esop
rote
rozo
ic
Gawler Craton
200 km
N
1000 km
North Australian Craton
WestAustralian
Craton GC
South Australian Craton
CP
28°00’
30°00’
32°00’
34°00’
138°00’
135°00’
132°00’
-5-
Chapter 1 Introducti on
associated with the Kimban Orogeny appears to have been principally of a moderate geothermal gradient. The associated deformati on, although widespread, is notable for the formati on of crustal scale shear zones such as the Kalinjala Shear Zone in the eastern Gawler Craton (Hand et al. 2007), the Tallacootra Shear Zone in the western Gawler Craton (Swain et al. 2005b), and probably the Karari Shear Zone in the central northern part of the shear zone. The Kimban Orogeny was associated with syn- to post- deformati onal felsic magmati sm over the interval ca 1690-1670 Ma (Payne et al. 2010).
Following the Kimban Orogeny, the 1.66 Ga Ooldean Event was associated with ultra-high temperature metamorphic conditi ons of around 950°C and 10kbars (Teasdale 1997, Hand et al. 2007) which reworked the immediately preceding metamorphism in the western Gawler Craton. At the same ti me, in the central Gawler Craton, depositi on of the Tarcoola Formati on at 1656 ± 8 Ma suggests a period of extension (Daly et al. 1998) and accompanied UHT metamorphism elsewhere in the craton.
Events in the Gawler Craton during the late Paleoproterozoic and Early Mesoproterozoic are dominated by igneous processes. The 1630-1610 Ma St Peter Suite and the associated Nuyts Volcanics, consisti ng of both mafi c and felsic intrusives, are thought to be related to subducti on processes (Fanning et al. 2007, Swain et al. 2008). This event was followed by widespread, mainly felsic magmati sm of the ca 1598-1575 Ma Hiltaba Suite and the associated ca 1590 Ma Gawler Range Volcanics (Daly et al. 1998, Budd 2006). The Hiltaba magmati sm was coincident with high T and UHT metamorphism and in the central northern Gawler Craton (Cutt s et al. 2011, Forbes et al. 2011). This deformati on and metamorphism was part of a widespread tectonothermal event that resulted in regional, medium to high grade metamorphism in
the easternmost Gawler Craton (Szpunar et al. 2007), and throughout the southern and eastern Curnamona Province (e.g. Rutherford et al. 2007). In the central northern Gawler Craton, high-grade metamorphic conditi ons persisted to around 1550-1530 Ma (Jagodzinski et al. 2010, Cutt s et al. 2011, Forbes et al. In Press).
At ca 1450 Ma the Karari, Tallacootra and Coorabie Shear Zones in the western Gawler Craton are thought to have undergone reacti vati on at greenschist or low-grade amphibolite conditi ons (Swain et al. 2005b, Fraser & Lyons 2006, Thomas et al. 2008). Subsequent to ca 1450 Ma, the northern and southwestern margins of the craton were thermally reworked during the Grenvillian-aged tectonism that was centred in the Musgrave Province but also conti nued into southwestern Australia (Daly et al. 1998). The eastern margin of the Gawler Craton was reworked during the Cambrian-Ordovician Delamerian Orogeny.
Although recent work has increased our understanding of geological history of the Gawler Craton, its tectonic evoluti on is sti ll not well understood. This is because Neoproterozoic and Phanerozoic sedimentary rocks and Cenozoic sediments cover much of the Gawler Craton. In parti cular, areas around the margins of the Gawler Craton, including the Nawa Domain in the northern Gawler Craton, and the Fowler Domain in the western Gawler Craton, have almost no outcrop and hence very litt le is known about them. Fortunately, basement-intersecti ng drill core from regional drilling programs has been preserved in these areas. While these drill holes pierce only very small areas of deeply buried basement, they off er a unique opportunity to gather criti cal tectonic informati on.
At the moment there is also a lack of understanding surrounding how the diff erent components of the Gawler Craton came
-6-
Chapter 1 Introducti on
together during the Proterozoic. There are also various diff erent models describing the ti ming and confi gurati on for the assembly of Proterozoic Australia (Myers et al. 1996, Daly et al. 1998, Dawson et al. 2002, Bett s & Giles 2006, Wade et al. 2006, Bett s et al. 2008, Payne et al. 2009), and the role of the Gawler Craton. These models are based on similariti es between the diff erent cratonic blocks of Proterozoic Australia, and thus are limited by our understanding of the individual cratonic blocks involved. On a much larger scale, Australia is oft en positi oned in varying arrangements adjacent to Laurenti a in larger conti nental scale reconstructi on models (Dalziel 1991, Hoff man 1991, Moores 1991, Brookfi eld 1993, Powell et al. 1993, Li et al. 1995, Blewett et al. 1998, Karlstrom et al. 1999, Burrett & Berry 2000, Goodge et al. 2002, Ross & Villeneuve 2003, Goodge et al. 2008).
One way to bett er constrain these reconstructi on models, on cratonic, conti nental and super-conti nental scales, is to investi gate the provenance of sedimentary successions in order to identi fy likely source regions which can in turn be considered in a paleogeographic context. To investi gate the provenance of sedimentary units this study uti lised a number of complimentary methods. Whole rock Sm-Nd isotopic analyses are used to determine the isotopic evoluti on of the average source region. Geochemistry is used to provide constraints about the compositi ons of the source region as well as informati on about the sedimentary processes involved. U-Pb zircon dati ng of detrital zircon provides a record of the zircon forming ti melines in the source region, and also provides maximum depositi onal age constraints which when combined with metamorphic zircon and monazite ages can constrain the depositi onal interval. As some zircon forming ti me lines can be common across many parts of the world, zircon ages are non-unique to the source region. However, with the use of Hf isotopic analyses from zircon grains, another
dimension is added to detrital zircon data allowing disti ncti ons to be made between similarly aged zircon populati ons.
Provenance studies are more eff ecti ve at constraining reconstructi on models if (meta)sedimentary rocks with similar depositi onal ages are analysed from a range of locati ons. In the Gawler Craton widespread sedimentati on occurred between ca 1790 – 1700 Ma (Daly et al. 1998, Hand et al. 2007, Szpunar et al. 2011). While across the Gawler Craton, Curnamona Province, Georgetown Inlier and Mount Isa Province, sedimentati on is known to have occurred at ca 1650 Ma (Daly et al. 1998, Page et al. 2005a, Page et al. 2005b, Lambeck et al. 2009, Lambeck et al. 2010). Targeti ng (meta)sedimentary rocks which were deposited at these ti mes for provenance studies off ers paleogeographic constraints that place the Gawler Craton into a wider context.
Another way to help constrain paleogeographic reconstructi on models is to match ti melines of magmati sm and metamorphism between conti nental blocks. As new geochronology is obtained from uncharacterised areas around the margin of the Gawler Craton, the potenti al exists to correlate the ti ming of magmati sm and metamorphism with other cratons from Proterozoic Australia as well as other crustal blocks around the world. For example, new magmati sm dated at 1780-1750 Ma from the northern Gawler Craton (this study) is identi cal to the ti ming of magmati sm from the Aileron Province in the North Australian Craton. Similarly, 1450 Ma magmati c and metamorphic ages collected from drill core in the northern Gawler Craton (this study) match with the Granite-Rhyolite Province of southern Laurenti a.
The aims of this project are:
1. To investi gate the provenance of (meta)sedimentary sequences of the Gawler Craton, and integrate the informati on with
-7-
Chapter 1 Introducti on
existi ng data in order to bett er understand the potenti al paleogeographic setti ng of the Gawler Craton
2. To constrain the ti melines of metamorphism and magmati sm in the western and northern Gawler Craton, and to match these events with other crustal blocks both within and external to Proterozoic Australia.
Both of these aims will help to constrain paleogeographic reconstructi on models which seek to explain the development of Proterozoic Australia within a wider context.
Thesis Outline
Chapter 2 shows that paleogeographic constraints based on provenance interpretati ons using age-only criteria should be treated with cauti on. The method commonly applied is to match the detrital zircon age spectra with the ages of zircon growth events in potenti al source regions. However, the ti ming of rock forming events in potenti al source regions is a non-unique criterion since equivalent age events can occur in unrelated tectonic systems. Chapter 2 presents a case study from the Gawler Craton. Detrital zircon ages from ca 1850 Ma metasedimentary rocks in the eastern Gawler Craton, correspond closely to the ages of zircon forming events within the older parts of the immediately adjacent (~50 km) craton, presenti ng a strong case that the sequences were derived from erosion of the Gawler Craton. However, bulk rock Nd and zircon Hf isotopic compositi ons within the metasedimentary units disprove derivati on solely from the proto Gawler Craton. This chapter has been published as “Detrital zircon ages: Improving interpretati on via Nd and Hf isotopic data” Howard, K.E., Hand, M., Barovich, K.M., Reid, A., Wade, B.P. and Belousova, E.A., 2009, Chemical Geology 262, 277-292.
Chapter 3 investi gates the provenance and depositi onal ti ming of metasedimentary
sequences in the poorly outcropping Fowler Domain of the western Gawler Craton. This study uti lises detrital zircon U-Pb and Lu-Hf isotopic data, bulk rock Sm-Nd isotopic and geochemical data to characterise the provenance of the metasedimentary rocks. Metamorphic monazite U-Pb age data has also been used to constrain the depositi onal interval of sedimentary protoliths within the Fowler Domain. The data allow the Fowler Domain to be assessed in the context of other metasedimentary-bearing domains in the southern Australian Proterozoic. This chapter has been published as “U-Pb, Lu-Hf and Sm-Nd isotopic constraints on provenance and depositi onal ti ming of metasedimentary rocks in the western Gawler Craton: Implicati ons for Proterozoic reconstructi on models” Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L. and Belousova, E.A., 2011, Precambrian Research 184, 43-62.
Chapter 4 investi gates the provenance and depositi onal ti ming of (meta)sedimentary sequences from the central Gawler Craton. Detrital zircon U-Pb and Lu-Hf isotopic data, bulk rock Sm-Nd isotopic and geochemical data are used to constrain the provenance of the sequences. These three sequences had previously been constrained to >1715 Ma, ca 1715 Ma and ca 1650. Recent provenance studies on ca 1760 - 1700 Ma cover sequences from the northern and western Gawler Craton and the Curnamona Province favour a North Australian Craton source region, implying a paleogeographic connecti on at the ti me of depositi on (Payne et al. 2006, Barovich & Hand 2008, Howard et al. 2011). Investi gati ng the provenance of similarly aged sequences can build upon existi ng datasets to bett er constrain proposed paleogeographic connecti ons for the amalgamati on of Proterozoic Australia. In additi on, the ti ming of depositi on of the youngest formati on (ca 1650 Ma) is identi cal to the ti ming of sedimentary depositi on of mineralised lithologies in the Curnamona
-8-
Chapter 1 Introducti on
Province and the Mt Isa and Georgetown Inlier of the North Australian Craton. Hence provenance informati on from 1650 Ma sedimentary sequence has the potenti al to add younger constraints to paleogeographic reconstructi ons, as well as provide a framework for mineral explorati on. This chapter has been published as “Provenance of late Paleoproterozoic cover sequences in the central Gawler Craton: exploring strati graphic correlati ons in eastern Proterozoic Australia using detrital zircon ages, Hf and Nd isotopic data” Howard, K.E., Hand, M., Barovich, K.M. and Belousova, E.A., 2011, Australian Journal of Earth Sciences 58, 475-500.
Chapter 5 investi gates the ages and characteristi cs of orthogneisses from drill core in the northern Gawler Craton. The northern Gawler Craton occupies a pivotal place in the architecture of Proterozoic Australia, forming the region that links the Meso-Neoarchean core of the Gawler Craton to the comparati vely juvenile Mesoproterozoic Musgrave Province. Due to an almost complete lack of outcrop and thick Neoproterozoic to Cenozoic cover, litt le is known about the basement rocks from the northern Gawler Craton. Compounding this problem is the scarcity of basement-intersecti ng drill holes in the area. Chapter 5 investi gates the ti ming, geochemistry and isotopic character of magmati c rocks in this region. The data allow correlati ons to be made between magmati c rocks of the northern Gawler Craton and other magmati c events from Proterozoic Australia. This chapter is published as “U-Pb zircon, zircon Hf and whole-rock Sm-Nd isotopic constraints on the evoluti on of Paleoproterozoic rocks in the northern Gawler Craton” Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Cutt s, K.A., and Belousova, E.A., 2011, Australian Journal of Earth Sciences 58, 615-638.
Chapter 6 presents new geochronology from drill core which reveals the existence of ca 1450 Ma magmati sm and high-grade
metamorphism in the northern Gawler Craton. This event has not previously been recognised in the Gawler Craton, however, it matches with the ti ming of cooling, resetti ng and shear zone reacti vati on across the Gawler Craton. It also matches with the ti ming of felsic magmati sm, Rb-Sr resetti ng and Ar-Ar cooling ages from regions across Proterozoic Australia including the Paterson Orogen, the Arunta Province, the Musgrave Province, the Mount Isa Province, the Georgetown Inlier, and beneath the Eucla Basin. Chapter 6 compiles the evidence for a widespread ca 1450 Ma tectonothermal event in Proterozoic Australia. The ti ming of this event matches with the ti ming of voluminous A-type magmati sm and regional deformati on associated with the Granite- Rhyolite Province in south western Laurenti a, and has been used as a basis for a conti nental reconstructi on involving Australia, Laurenti a, Cathaysia (South China) and Antarcti ca.
Chapter 7 concludes the thesis, provides a summary of the key fi ndings from the previous chapters, and includes discussion of some large scale implicati ons for reconstructi on models.
ReferencesBAROVICH K. & HAND M. 2008. Tectonic setti ng and provenance of the
Paleoproterozoic Willyama Supergroup, Curnamona Prov-ince, Australia: Geochemical and Nd isotopic constraints on contrasti ng source terrain components. Precambrian Research 166, 318-337.
BETTS P. G. & GILES D. 2006. The 1800-1100 Ma tectonic evoluti on of Australia. Precambrian Research 144, 92-125.
BETTS P. G., GILES D. & SCHAEFER B. F. 2008. Comparing 1800-1600 Ma accreti onary and basin processes in Australia and Laurenti a: Possible geographic connecti ons in Columbia. Precambrian Research 166, 81-92.
BLEWETT R. S., BLACK L. P., SUN S. S., KNUTSON J., HUTTON L. J. & BAIN J. H. C. 1998. U-Pb zircon and Sm-Nd geochronology of the Mesoproterozoic of North Queensland: implicati ons for a Rodinian connecti on with the Belt Supergroup of North America. Precambrian Research 89, 101-127.
BROOKFIELD M. E. 1993. Neoproterozoic Laurenti a-Australia fi t. Geology 21, 683-686.
BUDD A. R. 2006. The Tarcoola Goldfi eld of the Central Gawler Gold
-9-
Chapter 1 Introducti on
Province, and the Hiltaba Associati on Granites, Gawler Cra-ton, South Australia. PhD thesis, Australian Nati onal Univer-sity (Unpublished).
BURRETT C. & BERRY R. 2000. Proterozoic Australia-Western United States (AUSWUS) fi t between Laurenti a and Australia. Geol-ogy 28, 103-106.
CHALMERS N. C. 2007. Mount Woods Domain: Proterozoic metasedi-ments and intrusives. South Australia. Department of Pri-mary Industries and Resources. Report Book 2007/20.
CUTTS K., HAND M. & KELSEY D. E. 2011. Evidence for early Mesoprotero-zoic (ca. 1590Ma) ultrahigh-temperature metamorphism in southern Australia. Lithos 124, 1-16.
DALY S. J., FANNING C. M. & FAIRCLOUGH M. C. 1998. Tectonic evoluti on and explorati on potenti al of the Gawler Craton, South Aus-tralia. AGSO Journal of Australian Geology and Geophysics 17, 145-168.
DALZIEL I. W. D. 1991. Pacifi c margins of Laurenti a and East Antarcti ca-Australia as a conjugate rift pair: evidence and implicati ons for an Eocambrian superconti nent. Geology 19, 598-601.
DAWSON G. C., KRAPEZ B., FLETCHER I. R., MCNAUGHTON N. J. & RASMUS-SEN B. 2002. Did late Palaeoproterozoic assembly of proto-Australia involve collision between the Pilbara, Yilgarn and Gawler cratons? Geochronological evidence from the Mount Barren Group in the Albany-Fraser Orogen of West-ern Australia. Precambrian Research 118, 195-220.
DUTCH R. A., HAND M. & KELSEY D. E. 2010. Unravelling the tectono-thermal evoluti on of reworked Archean granulite facies metapelites using in situ geochronology: an example from the Gawler Craton, Australia. Journal of Metamorphic Geol-ogy 28, 293-316.
FANNING C. M., FLINT R. B., PARKER A. J., LUDWIG K. R. & BLISSETT A. H. 1988. Refi ned Proterozoic evoluti on of the Gawler Craton, South Australia, through U-Pb zircon geochronology. Pre-cambrian Research. The Early to Middle Proterozoic of Aus-tralia 40-41, 363-386.
FANNING C. M., REID A. J. & TEALE G. S. 2007. A Geochronological frame-work for the Gawler Craton, South Australia. South Austra-lia. Geological Survey. Bulleti n 55.
FORBES C. J., GILES D., HAND M., BETTS P. G., SUZUKI K., CHALMERS N. & DUTCH R. 2011. Using P-T paths to interpret the tectono-thermal setti ng of prograde metamorphism: An example from the northeastern Gawler Craton, South Australia. Pre-cambrian Research 185, 65-85.
FORBES C. J., GILES D., JOURDAN F., SATO K., OMORI S. & BUNCH M. In Press. Cooling and Exhumati on history of the northeastern Gawler Craton, South Australia. Precambrian Research.
FRASER G., MCAVANEY S., NEUMANN N., SZPUNAR M. & REID A. 2010. Dis-covery of early Mesoarchean crust in the eastern Gawler Craton, South Australia. Precambrian Research 179, 1-21.
FRASER G. L. & LYONS P. 2006. Timing of Mesoproterozoic tectonic acti vi-ty in the northwestern Gawler Craton constrained by Ar-40/
Ar-39 geochronology. Precambrian Research 151, 160-184.
GOODGE J. W., MYROW P., WILLIAMS I. S. & BOWRING S. A. 2002. Age and provenance of the Beardmore Group, Antarcti ca: Con-straints on Rodinia superconti nent breakup. Journal of Ge-ology 110, 393-406.
GOODGE J. W., VERVOORT J. D., FANNING C. M., BRECKE D. M., FARMER G. L., WILLIAMS I. S., MYROW P. M. & DEPAOLO D. J. 2008. A posi-ti ve test of East Antarcti ca-Laurenti a juxtapositi on within the Rodinia superconti nent. Science 321, 235-240.
HAND M., REID A. & JAGODZINSKI E. 2007. Tectonic framework and evo-luti on of the Gawler craton, southern Australia. Economic Geology 102, 1377-1395.
HOFFMAN P. F. 1991. Did the breakout of Laurenti a turn Gondwanaland inside-out? Science 252, 1409-1412.
HOPPER D. J. 2001. Crustal evoluti on of Palaeo- to Mesoproterozoic rocks in the Peake and Denison Ranges, South Australia. Unpublished Ph.D. thesis, Brisbane, Australia, University of Queensland.
HOWARD K. E., HAND M., BAROVICH K. M., PAYNE J. L. & BELOUSOVA E. A. 2011. U-Pb, Lu-Hf and Sm-Nd isotopic constraints on prov-enance and depositi onal ti ming of metasedimentary rocks in the western Gawler Craton: Implicati ons for Proterozoic reconstructi on models. Precambrian Research 184, 43-62.
JAGODZINSKI E., DUTCH R., DAVIES M. & FLINTOFF M. 2010. Digging up the dirt on the GOMA line. htt p://www.pir.sa.gov.au/__data/assets/pdf_fi le/0004/132754/Liz_Jagodzinski.pdf. SAREIC 2010 Technical Forum, Adelaide.
JAGODZINSKI E. A., REID A. J., CHALMERS N. C., SWAIN G., FREW R. A. & FOUDOULIS C. 2007. Compilati on of SHRIMP U-Pb geochro-nological data for the Gawler Craton, South Australia, 2007. South Australia. Department of Primary Industries and Re-sources Report Book, 2007/21.
KARLSTROM K. E., HARLAN S. S., WILLIAMS M. L., MCLELLAND J., GEISSMAN J. W. & ÅHÄLL K. I. 1999. Refi ning Rodinia: Geologic evidence for the Australia-Western U.S. Connecti on in the Protero-zoic. GSA Today 9, 2-7.
LAMBECK A., PARSONS A., BAROVICH K., HAND M., WITHNALL I. W., HUSTON D., NEUMANN N. & CARSON C. 2009. Sm-Nd isotopic fi nger-printi ng defi ning a ~1650 Ma reference boundary in Mt Isa and Georgetown: Implicati ons for Zn-Pb explorati on. Dig-ging Deeper 7 Brisbane.
LAMBECK A., HUSTON D., NEUMANN N., BAROVICH K. & HAND M. 2010. Reconstructi on of the Australian-Laurenti a link at 1650 Ma: Constraints from Sm-Nd data from the Georgetown, Mount Isa, Curnamona, Yavapai and Mazatzal provinces SGTSG 2010 Port Macquarie (unpubl.).
LI Z. X., ZANG L. & POWELL C. M. 1995. South China in Rodinia: part of the missing link between Australia-East Antarcti ca and Lau-renti a? Geology 23, 407-410.
MCFARLANE C. R. M. 2006. Palaeoproterozoic evoluti on of the Challeng-er Au Deposit, South Australia, from monazite geochronol-
-10-
Chapter 1 Introducti on
ogy. Journal of Metamorphic Geology 24, 75-87.
MOORES E. M. 1991. Southwest US-East Antarcti c (SWEAT) connecti on: a hypothesis. Geology 19, 425-428.
MYERS J. S., SHAW R. D. & TYLER I. M. 1996. Tectonic evoluti on of Pro-terozoic Australia. Tectonics 15, 1431-1446.
OLIVER R. L. & FANNING C. M. 1997. Australia and Antarcti ca; precise correlati on of Palaeoproterozoic terrains. In: C.A R. ed., The Antarcti c region; geological evoluti on and processes; pro-ceedings of the VII internati onal symposium on Antarcti c earth sciences., Vol. 7, pp 163-172, Terra Antarcti ca Publica-ti on, Siena, Italy.
PAGE R. W., CONOR C. H. H., STEVENS B. P. J., GIBSON G. M., PREISS W. V. & SOUTHGATE P. N. 2005a. Correlati on of Olary and Broken Hill Domains, Curnamona Province: possible relati onship to Mount Isa and other North Australian Pb-Zn-Ag-bearing succesions Economic Geology 100, 663-676.
PAGE R. W., STEVENS B. P. J. & GIBSON G. M. 2005b. Geochronology of the sequence hosti ng the Broken Hill Pb-Zn-Ag orebody, Australia. Economic Geology 100, 633-651.
PAYNE J. L., BAROVICH K. M. & HAND M. 2006. Provenance of metasedi-mentary rocks in the northern Gawler Craton, Australia: Im-plicati ons for palaeoproterozoic reconstructi ons. Precam-brian Research 148, 275-291.
PAYNE J. L., HAND M., BAROVICH K. M. & WADE B. P. 2008. Temporal con-straints on the ti ming of high-grade metamorphism in the northern Gawler Craton: implicati ons for assembly of the Australian Proterozoic. Australian Journal of Earth Sciences 55, 623-640.
PAYNE J. L., HAND M., BAROVICH K. M., REID A. & EVANS D. A. D. 2009. Correlati ons and reconstructi on models for the 2500-1500 Ma evoluti on of the Mawson Conti nent. Geological Society Special Publicati on: 319-355.
PAYNE J. L., FERRIS G., BAROVICH K. M. & HAND M. 2010. Pitf alls of clas-sifying ancient magmati c suites with tectonic discriminati on diagrams: An example from the Paleoproterozoic Tunkillia Suite, southern Australia. Precambrian Research 177, 227-240.
POWELL C. M., LI Z. X., MCELHINNY M. W., MEERT J. G. & PARK J. K. 1993. Paleomagneti c constraints on ti ming of the Neoproterozoic breakup of Rodinia and the Cambrian formati on of Gond-wana. Geology 21, 889-892.
RANKIN L. R., FLINT R. B. & FANNING C. M. 1988. The Bosanquet Forma-ti on of the Gawler Craton. South Australia Geological Sur-vey. Quarterly Geological Notes 105, 12-18.
REID A., HAND M., JAGODZINSKI E., KELSEY D. & PEARSON N. 2008. Paleo-proterozoic orogenesis in the southeastern Gawler Craton, South Australia. Australian Journal of Earth Sciences 55, 449-471.
ROSS G. M. & VILLENEUVE M. 2003. Provenance of the Mesoprotero-zoic (1.45 Ga) Belt basin (western North America): Another piece in the pre-Rodinia paleogeographic puzzle. Bulleti n of
the Geological Society of America 115, 1191-1217.
RUTHERFORD L., HAND M. & BAROVICH K. 2007. Timing of Proterozoic metamorphism in the southern Curnamona Province: Im-plicati ons for tectonic models and conti nental reconstruc-ti ons. Australian Journal of Earth Sciences 54, 65-81.
SWAIN G., WOODHOUSE A., HAND M., BAROVICH K., SCHWARZ M. & FAN-NING C. M. 2005a. Provenance and tectonic development of the late Archaean Gawler Craton, Australia; U-Pb zircon, geochemical and Sm-Nd isotopic implicati ons. Precambrian Research 141, 106-136.
SWAIN G., BAROVICH K., HAND M., FERRIS G. & SCHWARZ M. 2008. Petro-genesis of the St Peter Suite, southern Australia: Arc mag-mati sm and Proterozoic crustal growth of the South Austra-lian Craton. Precambrian Research 166, 283-296.
SWAIN G. M., HAND M., TEASDALE J., RUTHERFORD L. & CLARK C. 2005b. Age constraints on terrane-scale shear zones in the Gawler Craton, southern Australia. Precambrian Research 139, 164-180.
SZPUNAR M., HAND M., BAROVICH K. & JAGODZINSKI E. 2007. Age and provenance of the Palaeoproterozoic Hutchison Group, southern Gawler Craton, South Australia. SGTSG 2007 - De-formati on in the Desert, Alice Springs. Geological Society of Australia.
SZPUNAR M., HAND M., BAROVICH K., JAGODZINSKI E. & BELOUSOVA E. 2011. Isotopic and geochemical constraints on the Paleo-proterozoic Hutchison Group, southern Australia: Implica-ti ons for Paleoproterozoic conti nental reconstructi ons. Pre-cambrian Research 187, 99-126.
TEASDALE J. 1997. Methods for understanding poorly exposed terranes: The interpreti ve geology and tectonothermal evoluti on of the western Gawler Craton. Geology and Geophysics, Uni-versity of Adelaide, Adelaide (unpubl.).
THOMAS J. L., DIREEN N. G. & HAND M. 2008. Blind orogen: Integrated appraisal of multi ple episodes of Mesoproterozoic defor-mati on and reworking in the Fowler Domain, western Gawl-er Craton, Australia. Precambrian Research 166, 263-282.
WADE B. P., BAROVICH K. M., HAND M., SCRIMGEOUR I. R. & CLOSE D. F. 2006. Evidence for early Mesoproterozoic arc magmati sm in the Musgrave Block, central Australia: Implicati ons for Proterozoic crustal growth and tectonic reconstructi ons of Australia. Journal of Geology 114, 43-63.
Chapter 2
This chapter is published as:
Howard, K.E., Hand, M., Barovich, K.M., Reid, A., Wade, B.P., Belousova, E.A., 2009. Detrital zir-con ages: Improving interpretati on via Nd and Hf isotopic data. Chemical Geology, 262, 277-292.
-15-
Detrital zircon ages: Improving interpretation via Nd and Hf isotopic data
Katherine E. Howard a,⁎, Martin Hand a, Karin M. Barovich a, Anthony Reid b,Benjamin P. Wade a, Elena A. Belousova c
a Continental Evolution Research Group, School of Earth and Environmental Sciences, University of Adelaide, Adelaide, SA 5005, Australiab Geological Survey, Department of Primary Industries and Resources, Adelaide, SA, 5000, Australiac ARC National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC), Department of Earth and Planetary Sciences, Macquarie University, NSW 2109, Australia
a b s t r a c ta r t i c l e i n f o
Article history:Received 13 August 2008Received in revised form 28 January 2009Accepted 29 January 2009
Editor: R.L. Rudnick
Keywords:ProvenanceProterozoicNd isotopesHf isotopesDetrital zirconGawler Craton
The bulk of sedimentary provenance studies use similarities in the detrital zircon age patterns or “barcodes”in sedimentary systems and potential source regions to make interpretations about palaeogeographicsettings. While this “age-only” approach is generally considered to be effective, it is limiting because thetiming of zircon growth events may not be unique to specific terrains and important rock forming events maybe associated with little zircon growth.To a significant extent these limitations can be overcome by employing additional isotopic data sets such asSm–Nd and Lu–Hf that provide information on the crustal evolution of the source region, and allowcomparisons with sedimentary packages. As an example, the age spectra of detrital zircons inPalaeoproterozoic metasedimentary rocks in the eastern Gawler Craton in southern Australia are virtuallyidentical to the dominant zircon growth timelines in adjacent older domains of the Gawler Craton,presenting a prima facie case that it was the source region. However, whole rock Nd isotopic data indicatethat the pre-existing proto Gawler Craton was isotopically too crustally evolved (εNd (1850 Ma)−10) to havesupplied the bulk of the sediment to the relativelymore juvenilemetasedimentary units (εNd (1850 Ma)−1 to−5).In addition, zircon Hf isotopic compositions from ca 2000 Ma detrital zircons in the metasedimentary rocks(εHf (2000 Ma)+2 to +5) are significantly more juvenile than 2000 Ma rocks in the adjacent Gawler Craton(εHf (2000 Ma)−2 to−5). The combination of bulk rockNd andHf zircon data suggest that theGawler Craton is nota viable source region for the metasedimentary packages, despite the striking similarity between detrital zirconages and zircon crystallisation events within the craton.
© 2009 Elsevier B.V. All rights reserved.
1. Introduction
A key requirement of any palaeogeographical model is that itsatisfies available geological constraints. Such constraints may includecorrelations based on the ages of events in the connecting orogenicbelts, palaeomagnetic constraints and overlap of sedimentary geo-chemical and temporal provenance patterns. The event chronology inorogenic belts can be used as piercing points between riftedcontinental fragments with similarities in events and styles as abasis for correlation (e.g. Burrett and Berry, 2000; Karlstrom et al.,2001; Foden et al., 2006). Palaeomagnetic data can provide con-straints on the locations of continental landmasses, with similarities inpolar wander paths suggesting continental regions had a commonmotion and therefore a connection for reconstruction models (e.g.Idnurm and Giddings, 1995; Karlstrom et al., 1999; Burrett and Berry,2000; Wingate et al., 2002). The provenance of sedimentary rocks(and their metamorphosed equivalents) can provide palaeogeo-graphic constraints if they can be plausibly connected with their
potential source regions (e.g. Cawood et al., 2003; Collins et al., 2003;Darby and Gehrels, 2006; Cawood et al., 2007). In some instancesthese ages and compositions appear to be sufficiently unique toprovide a restrictive constraint linking once proximal regions (e.g.Collins et al., 2003; Fitzsimons and Hulscher, 2005; Payne et al., 2006).
The use of detrital zircons in provenance studies has become aprimary tool in understanding tectonic amalgamation and palaeogeo-graphic reconstructions (e.g. Collins et al., 2003; Fitzsimons andHulscher, 2005; Payne et al., 2006; Cawood et al., 2007). The methodcommonly applied is to match the detrital zircon age spectra with theages of zircon growth events in potential source regions. This “age-only” approach, although elementary, has been shown to offersignificant constraints on palaeogeographic and tectonic models(Dickinson and Gehrels, 2003; Friend et al., 2003; Gillis et al., 2005;Samson et al., 2005; Talavera-Mendoza et al., 2005; Carter et al., 2006;Darby and Gehrels, 2006; Gleason et al., 2007; Kirkland et al., 2007).However, there are several significant limitations with the age-onlyapproach which are discussed in Moecher and Samson (2006):(1) source regions are not all equally fertile for zircon production, withsome source terranes not represented by zircon growth at all;(2) magmatic or thermotectonic events may not be represented by
⁎ Corresponding author. Tel.: +61 8 8303 4971; fax: +61 8 8303 6222.E-mail address: [email protected] (K.E. Howard).
0009-2541/$ – see front matter © 2009 Elsevier B.V. All rights reserved.doi:10.1016/j.chemgeo.2009.01.029
-16-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
zircon growth; (3) tectonometamorphic events may not be recorded,or may produce zircon rims of insufficient volume to analyse with thechosen method. Furthermore a number of sampling problems arehighlighted by Andersen (2005) which include biases in apparentzircon age populations due to insufficient numbers of analysed grains.Additional limitations include: (1) Source regions may not be easilyidentified, due to a paucity of outcrop or erosion of the source rocks,making “barcode” matching difficult; (2) The timing of rock formingevents in potential source regions is a non-unique criterion sinceequivalent age events can occur in unrelated tectonic systems. Whilesome limitations can not be easily overcome (such as the lack ofoutcropping source regions), many other limitations can be addressedwith additional analytical methods.
In recent years it has been increasingly recognised that additionalinformation is needed to inform the interpretation of detrital zirconage data (e.g. Veevers et al., 2005; Augustsson et al., 2006; Veeverset al., 2006; Yang et al., 2006; Banks et al., 2007). In particular Sm–Ndwhole rock and Lu–Hf zircon isotopic data can place importantadditional constraints (Andersen, 2005; Veevers et al., 2005;Augustsson et al., 2006; Veevers et al., 2006; Yang et al., 2006;Banks et al., 2007). Whole rock Nd isotopic data can reveal the relativeinput of juvenile material derived from the mantle compared withcrustally evolved material recycled from the crust (Barovich andFoden, 2000; McLennan et al., 2003; Patchett, 2003), and incombination with geochemistry, can be useful in identifying sourceregions dominated by mafic lithologies. This then provides anotherconstraint which must be matched between sedimentary rocks andpotential source regions.
Hf isotope data can be applied in a similar way to whole rock Ndisotope compositions (Amelin et al., 2000; Patchett, 2003; Schereret al., 2007). However, Hf zircon isotopic compositions determine thecontributions of juvenile and crustally evolved material withinindividual zircon grains. Hf isotopic data combined with U–Pb datingenables a distinction to be made between zircon grains that haveformed at the same time but with different ratios of crustal andmantle contributions (Amelin et al., 2000; Patchett, 2003; Schereret al., 2007), and therefore may identify different source regions. Inrecognition of this, detrital zircon studies are increasingly using Hfisotopic data to better constrain potential source regions (Veeverset al., 2005; Augustsson et al., 2006; Veevers et al., 2006; Yang et al.,2006).
In this study we demonstrate that palaeogeographic constraintsbased on provenance interpretations using age-only criteria should betreated with caution. Detrital zircon ages from ca 1850 Ma metase-dimentary rocks in the eastern Gawler Craton, South Australia,correspond closely to the ages of major rock forming events withinthe older parts of the immediately adjacent (∼50 km) craton,presenting a strong prima facie case that the sequences were derivedfrom erosion of the Gawler Craton. However, bulk rock Nd and zirconHf isotopic compositions within the metasedimentary units disprovederivation solely from the proto Gawler Craton. Within the Australiancontext, the only plausible source region based on the Hf isotopiccompositions of the detrital zircons is the Pine Creek Orogen, some3000 km away in the North Australian Craton. This case study showsthat Nd and Hf isotope compositional information is as critical as theages of detrital zircons in the interpretation of provenance data.
2. Geological setting
The Gawler Craton in the South Australian Craton (Fig. 1) wasformed during two main periods of tectonic activity. Late Archaean(2560–2500Ma) to Palaeoproterozoic (ca 2000–1850Ma) units makeup the basement, which are intruded and overlain by late Palaeopro-terozoic (1750–1600 Ma) to early Mesoproterozoic (1600–1550 Ma)rocks (Daly et al., 1998; Swain et al., 2005; Hand et al., 2007). In theeastern Gawler Craton, the crustal scale Kalinjala Shear Zone, divides
Archaean and late Palaeoproterozoic rocks to the west fromdominantly mid-Palaeoproterozoic rocks to the east (Fig. 1).
2.1. West of the Kalinjala Shear Zone
To the west of the Kalinjala Shear Zone, the pre-1850 Ma south-eastern Gawler Craton is made up of late Archaean metasedimentaryand volcanic units that were intruded by comparatively juvenilegranites between 2520 and 2500 Ma referred to as the Sleaford andMulgathing Complexes (Daly et al., 1998). These granites include theCoulta Granodiorite (Daly et al., 1998), which is interpreted torepresent remnants of a rifted late Archaean arc (Swain et al., 2005)through which komatiites were erupted at 2510 Ma. The LateArchaean rocks underwent greenschist to granulite-grade meta-morphism between 2480 and 2420 Ma during the SleafordianOrogeny, which was also associated with the emplacement of2440 Ma, mostly crustally derived, granites (Daly et al., 1998).
Following a period of apparent tectonic quiescence between 2400and 2000 Ma, renewed tectonic activity was marked by the emplace-ment of the protoliths to the Miltalie Gneiss at 2000 Ma (Fanning et al.,2007), which outcrops sporadically over a distance of ca 250 km alongthe eastern Eyre Peninsula. These 2000Ma igneous rocks and associatedmetasedimentary units underwent high-grade metamorphism anddeformation sometime in the interval 2000–1850 Ma (Hand et al.,2007).
The Miltalie Gneiss is unconformably overlain by the WarrowQuartzite (the basal unit to the metasedimentary Hutchison Group).The minimum depositional age for the Hutchison Group is consideredto be 1845±9 Ma which is the U–Pb age of the volcanic BosanquetFormation interpreted to occur toward the top of the Hutchison Group(Rankin et al., 1990; Fanning, 1997; Daly et al., 1998; Fanning et al.,2007).
2.2. East of the Kalinjala Shear Zone
To the east of the Kalinjala Shear Zone the geology is dominated bythe 1850 Ma Donington Suite (Hoek and Schaefer, 1998; Ferris et al.,2002; Reid et al., 2008) which forms a batholithic-scale feature at least500 km by 70 km in current extent (Fairclough and Daly, 1995; Reidet al., 2008). The eastern outcroppingmargin of the Donington Suite isdefined by younger cover sequences ranging in age from ca 1760Ma torecent (Daly et al., 1998), and the full eastward extent of theDonington Suite is unknown. The Donington Suite ranges frommonzonitic to granitic in composition and has been intruded bynumerous syn-magmatic mafic dykes (Hoek and Schaefer,1998; Ferriset al., 2002; Reid et al., 2008).
Country rocks to the Donington Suite are rarely preserved.However, there is a region containing a metasedimentary packagethat provides access to the crust intruded by the Donington Suite. Onsouthwestern Yorke Peninsula, the Corny Point Paragneiss is ametasedimentary package ranging from psammitic to pelitic incomposition that preserves intrusive relationships with the Doning-ton Suite constraining its minimum depositional age to ca. 1850 Ma(Zang, 2002; Reid et al., 2008). Although separated by the KalinjalaShear Zone, the Corny Point Paragneiss has apparently similarminimum depositional age constraints to the Warrow Quartzite,which forms the base of the regionally extensive 2000–1850 MaHutchison Group (Fig. 1). The Corny Point Paragneiss and its detritalzircon and isotopic data are the focus of this study.
3. Analytical methods
3.1. U–Pb zircon dating
Analytical techniques for U–Pb isotopic dating of zircons followthose of Payne et al. (2006) andWade et al. (2008a). Zircons obtained
-17-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
Fig.1.Map
oftheinterpretedcrystalline
basemen
tgeo
logy
oftheGaw
lerCraton
,Sou
thAus
tralia,sho
wingsamplelocation
sfortheCo
rnyPo
intP
arag
neiss,theCo
ulta
Grano
dioritean
dtheMiltalie
Gne
iss(Faircloug
han
dDaly,19
95).Maininset
show
sade
taile
dmap
ofCo
rnyPo
int,Yo
rkePe
nins
ulaan
dsamplelocation
swithintheCo
rnyPo
intPa
ragn
eiss
(Richa
rdson,
1978
).Sm
allins
etsh
owstheGaw
lerCraton
inrelation
toothe
rPa
laeo
proteroz
oicterrains
ofAus
tralia.
N
OTE
: T
his f
igur
e is
incl
uded
on
page
17
o
f the
prin
t cop
y of
the
thes
is h
eld
in
the
Uni
vers
ity o
f Ade
laid
e Li
brar
y.
-18-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
from samples of the Corny Point Paragneiss, as well as the CoultaGranodiorite, the Miltalie Gneiss and a collection of Miltalie Gneissderived stream sediments from the pre-1850 Ma rocks in the easternGawler Craton to the west of the Kalinjala Shear Zone were datedby U-Pb methods. Rocks were jaw crushed and sieved, collecting the79–300 μm portion. Zircon separates were obtained via panning,Frantz (at 0.6 nT), and heavy liquid methods before being hand pickedand mounted into epoxy resin blocks. Zircon grains were CL imagedusing a Phillips XL-20 SEM with attached Gatan Cathode Lumines-cence. U–Pb isotopic analyses were obtained using a New Wave213 nm Nd-YAG laser with attachment on spectroscope in a Heablation atmosphere, coupled to an Agilent 7500cs ICP-MS at theUniversity of Adelaide. The laser pit diameter was 40 μm, with a typicaltotal depth of 40–50 μm. U–Pb fractionation was corrected using theGEMOC GJ-1 zircon (TIMS normalisation data 207Pb/206Pb=608.3 Ma,206Pb/238U=600.7 Ma and 207Pb/235U=602.2 Ma, (Jackson et al.,2004)). Accuracy was checked with an in-house Sri Lankan zirconstandard (BJWP-1, ca 720 Ma). Over the duration of this study thereported average normalised ages for GJ-1 are 608.9±17.3 Ma, 600.7±9.2Ma, 602.4±7.7Ma for the 207Pb/206Pb, 206Pb/238Uand 207Pb/235U,respectively (2σ, n=127). The 207Pb/206Pb grain ages were used, andspot errors are reported at 1 sigma. A number of zircon grains wereexcluded from analysis due to metamictisation and small size. Detritalcores larger than 40 μm in size were targeted, as well as some largemetamorphic rims. In the data interpretation, a b10% discordancythresholdwas used for all grains analysed. Probability density plots havebeen constructed using Isoplot version 3.0 (Ludwig, 2003).
3.2. Whole-rock Sm–Nd isotopic analyses
Analytical techniques and analysis for whole rock Sm–Nd isotopicdata follow those of Wade et al. (2005) and Payne et al. (2006) andwere done at the University of Adelaide. Samples were spiked with a150Nd–147Sm solution. HF was added to the sample in Teflon ‘bombs’and evaporated. The samples were then oven-heated at 190°C for5 days in HF in sealed Teflon bombs. The HFwas then evaporated, withHNO3 added shortly before samples were completely dry. 6 MHCl wasadded and samples were heated for 2 days at 160°C. REE wereseparated in Biorad Polyprep columns, and were further separated inHDEHP-impregnated Teflon-powder columns to isolate Sm and Nd.Nd was run on a Finnigan MAT 262 Thermal Ionisation Mass Spec-trometer (TIMS) and Sm was run on a MAT 261 TIMS. The La Jolla andJNdi-1 standards give long term running averages of 0.511834±0.000018 (2σ, n=96) and 0.512092±0.000016 (2σ, n=164)respectively. Epsilon values were calculated relative to a chondritepresent day 143Nd/144Nd value of 0.512638 and 147Sm/144Nd value of0.1966 (Goldstein et al., 1984). Crustal residence ages relative to thedepleted mantle (TDM) assume present day 143Nd/144Nd value of0.513114 and a 147Sm/144Nd DM value of 0.222 (Michard et al., 1985).
3.3. Zircon Hf isotopic analyses
Analyticalmethods for zirconHf isotopedeterminationaredescribedin detail in Griffin et al. (2006a) and are summarised below. Analyseswere carried out in situ with a New Wave/Merchantek UP-213 laser-ablation microprobe, attached to a Nu Plasma multi-collector ICP-MS,at Macquarie University, Sydney. The NewWave/Merchantek LUV lasersystemdelivers a beamof 213nmUV light froma frequency-quadrupledNd:YAG laser. Most analyses were obtained using a beam diameterof 55 μm and a 5 Hz repetition rate resulting in typical Hf signals of1–5×10−11 A. Typical ablation times were 80–120 s, resulting in pits40–50 μm deep.
For this work we analysed masses 172, 175, 176, 177, 178, 179 and180 simultaneously in Faraday cups; all analyses were carried out instatic-collection mode. Data were normalized to 179Hf/177Hf=0.7325,using an exponential correction for mass bias. Initial setup of the
instrument is done using a 1 ppm solution of JMC475 Hf whichtypically yields a total Hf beam of 10–14×10−11 A.
Interference of 176Lu on 176Hf is corrected bymeasuring the intensityof the interference-free 175Lu isotope and using 176Lu/175Lu=0.02669(Patchett, 1983) to calculate 176Lu/177Hf. Similarly, the interference of176Yb on 176Hf has been corrected by measuring the interference-free172Yb isotope and using 176Yb/172Yb to calculate 176Yb/177Hf. Theappropriate value of 176Yb/172Yb was determined by spiking theJMC475 Hf standard with Yb, and finding the value of 176Yb/172Yb(0.5865) required to yield the value of 176Hf/177Hf obtained on the pureHf solution (Griffin et al., 2004). The accuracy of the Yb and Lucorrections has been demonstrated by repeated analysis of standardzirconswith a range in 176Yb/177Hf and 176Lu/177Hf (Griffin et al., 2004).
Before and during the analysis of unknowns the Mud Tank zircons(Griffin et al., 2004)were analysed to check instrument performance andstability (Table 1). TheMud Tank standard analysed during this study hasan average corrected 176Hf/177Hf value of 0.282515±0.000026 (2σ,n=11). This is similar to the long term running average of 0.282523±0.000043 (2σ, n=2190) (Griffin et al., 2006b). Additionally over themonth inwhichanalyseswere collected, the91500 zircon standard,witha reported 176Lu/177Hf value of 0.000317±0.000054 (2σ; Griffin et al.,2006b), had an average corrected 176Hf/177Hf value of 0.282302±0.000021 (2σ, n=6). This is well within error of the long term runningaverage of 0.282307±0.000058 (2σ, n=632; Griffin et al., 2006b).
The measured 176Lu/177Hf ratios of the zircons have been used tocalculate initial 176Hf/177Hf ratios. These age corrections are verysmall, and the typical uncertainty on a single analysis of 176Lu/177Hf(+1%) contributes an uncertainty of b0.05 εHf unit.
There are currently several proposed values for the 176Lu decayconstant which range between 1.983×10−11 and 1.865×10−11 (Bli-chert-Toft and Albarede, 1997; Scherer et al., 2001; Bizzarro et al., 2003;Soderlund et al., 2004). The decay constants of Blichert-Toft andAlbarede (1997) and Bizzarro et al. (2003) have been calculated frommeteorite samples, while the decay constants of Scherer et al. (2001)and Soderlund et al. (2004) have been calculated from terrestrialsamples. For the calculation of εHf, we have adopted a decay constant for176Lu of 1.865×10−11 y−1 (Scherer et al., 2001).
Chondritic values of 176Hf/177Hf=0.0332 and 176Lu/177Hf=0.282772(Blichert-Toft and Albarede, 1997) have been used. These values arereported relative to 176Hf/177Hf=0.282163 for the JMC475 standard.
Depletedmantlemodel ages (TDM), also knownas single stagemodelages,were calculatedusing themeasured 176Lu/177Hf ratios, referred to amodel depleted mantle with present day 176Hf/177Hf ratio of 0.28325(Nowell et al.,1998) and 176Lu/177Hf ratio of 0.0384 (Griffin et al., 2000).
Table 1Zircon reference material analyses.
Analysis 176Lu/177Hf 176Yb/177Hf 176Hf/177Hf 2 SE
MT-06-257 0.000047 0.002127 0.282520 0.000024MT-06 258 0.000045 0.001937 0.282517 0.000017MT-06-260 0.000042 0.002028 0.282516 0.000030MT-06-261 0.000021 0.000746 0.282500 0.000015MT-06-261 0.000050 0.002247 0.282515 0.000019MT-06-262 0.000053 0.002306 0.282549 0.000034MT-06-263 0.000046 0.001935 0.282532 0.000026MT-06-264 0.000039 0.001604 0.282507 0.000044MT-06-265 0.000055 0.002233 0.282505 0.000034MT-06-266 0.000052 0.002210 0.282500 0.000030MT-06-267 0.000020 0.000716 0.282509 0.000013Mudtank average 0.000043 0.001826 0.282515 0.00002691500-06-07 0.000321 0.011455 0.282289 0.00002091500-06-08 0.000311 0.008644 0.282289 0.00001691500-06-09 0.000320 0.008994 0.282289 0.00003291500-06-10 0.000305 0.009293 0.282292 0.00001791500-06-11 0.000322 0.009169 0.282333 0.00002291500-06-12 0.000316 0.009024 0.282317 0.00001891500 average 0.000316 0.009430 0.282302 0.000021
-19-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
Crustal model ages, assuming derivation from a depleted mantle (TDMc ),otherwise known as two stage model ages, were calculated for thesource rock of themagma using the initial 176Hf/177Hf ratio of the zirconand assuming amean crustal value of 176Lu/177Hf=0.0015 (Griffin et al.,2002).
4. Results
4.1. LA-ICP-MS U–Pb detrital zircon data from the Corny Point Paragneiss
Three samples (CP-2003-05, CP-2006-10 and CP-2006-18) wereused for U–Pb zircon age analyses. Physical structures of the analysedzircons are summarised in Table 2. U–Pb zircon ages of the samplescollected from the Corny Point Paragneiss are available in theelectronic supplement, while concordia plots and probability densitydiagrams in Fig. 2.
Zircons from the three Corny Point Paragneiss samples used in thisstudy are 70–250 μm in size, yellow to colourless, and rounded towellrounded in shape. The internal structure of these detrital zirconsvaries from strong oscillatory zoning to almost homogeneous. Internalgrowth patterns are visible in some of the grains, while cores can beclearly identified in others. Internal growth domains were targeted ifcores were not clearly defined.
Of the 182 zircon grains analysed from the Corny Point Paragneiss,116 are within 10% discordancy and provide a sample age rangefrom 1852±18 Ma to 2769±16 Ma (Fig. 2). Samples CP-2003-05 andCP-2006-10 are metapelites and share age populations at 1900 Ma,2000–2020 Ma, and 2450 Ma with smaller peaks at 2160 Ma, and2500–2520 Ma. In addition CP-2006-10 has age population peaks at2060 Ma, 2340 Ma and 2650 Ma. Metapsammite CP-2006-18 hasdetrital zircon age peaks at 2000–2020 Ma, 2060 Ma, 2420 Ma,2510 Ma with minor peaks at 2200 Ma, 2670 Ma and 2770 Ma. Theyoungest detrital zircon grains from samples CP-2003-05, CP-2006-10and CP-2006-18 within 10% discordancy have ages at 1881±18 Ma,1852±18 Ma and 1946±18 Ma respectively.
4.2. LA-ICP-MS U–Pb zircon data from Gawler Craton samples
Since the N1850 Ma components of the adjacent Gawler Craton arean obvious source for the protoliths of the Corny Point Paragneiss,additional U–Pb zircon data was collected from this region to providecomparative data to explore its potential as a source region. Zirconsfrom the Coulta Granodiorite on western Eyre Peninsula (Fig. 1) havewell preserved igneous morphologies (Table 2). U–Pb data from 9concordant zircons define a population with a mean age of 2524±11 Ma (Fig. 2), which is interpreted to be the crystallisation age of therock. This age is consistent with a SHRIMP zircon U–Pb age of 2519±8 Ma from the same intrusive suite (Fanning et al., 2007).
The ca 2520 –2450 Ma rock system in the eastern Gawler Craton isintruded by ca 2000 Ma granodioritic rocks referred to as the MiltalieGneiss (Daly et al., 1998; Hand et al., 2007). U–Pb zircon dating fromigneous-style zircons from the Miltalie Gneiss (Fig. 2) yields aninterpreted crystallisation age of 2017±10 Ma (Fig. 2). This age issimilar to existing SHRIMP ages of 2002 ±15 Ma, 1999±13 Ma and2001±8 Ma (Fanning et al., 2007).
In addition, three localised stream sediment samples were takenfromvarious locations within the outcropping Miltalie Gneiss in orderto examine potential age heterogeneity. Zircon ages from these streamsamples were collated together (Miltalie composite), and have adominant population at 2012±14 Ma (Fig. 2). A significantly youngerpopulation around 1200 Ma in age is ∼250 Ma younger than the lastknown tecotonothermal event in the Gawler Craton (Hand et al., 2007)and is interpreted to belong to a windblown component derived fromthe Musgrave Province in central southern Australia (Belousova et al.,2006; Wade et al., 2008b). The ages of these young grains are notconsidered relevant to the evolution of the high-grade Miltalie Gneiss. Ta
ble2
Description
sof
zircon
sfrom
alls
amples
analysed
.
Sample
Location
Rock
unit
Size
Colour
A.R.
Shap
eCL
description
CP-05
137°
01′03
″–34
°53
′46
″Co
rnyPo
intPa
ragn
eiss
(∼18
50Ma)
70–25
0μm
Yello
wto
colourless
1:2
Roun
dedto
wellrou
nded
withtabu
largrains
,oc
casion
alne
edle
shap
eSm
allc
ores
surrou
nded
bynu
merou
sov
ergrow
thsrimswithzo
ning
rang
ingfrom
oscilla
tory
tominim
al.D
iffus
ean
dmetam
ictfeatures
insomeof
thegrains
.CP
-200
6-10
137°
00′51
″–34
°53
′40
″Co
rnyPo
intPa
ragn
eiss
(∼18
50Ma)
70–25
0μm
Yello
wto
colourless
1:2
Roun
dedto
wellrou
nded
withtabu
largrains
,oc
casion
alne
edle
shap
eSm
allc
ores
surrou
nded
bynu
merou
sov
ergrow
thsrimswithzo
ning
rang
ingfrom
oscilla
tory
tominim
al.D
iffus
ean
dmetam
ictfeatures
insomeof
thegrains
.CP
-200
6-18
137°
00′53
″–34
°53′
36″
CornyPo
intPa
ragn
eiss
(∼18
50Ma)
70–25
0μm
Yello
wto
colourless
1:2
Roun
dedto
wellrou
nded
withtabu
largrains
,oc
casion
alne
edle
shap
eSm
allc
ores
surrou
nded
bynu
merou
sov
ergrow
thsrimswithzo
ning
rang
ingfrom
oscilla
tory
tominim
al.D
iffus
ean
dmetam
ictfeatures
insomeof
thegrains
.CG
135°
13′26
″–34
°07
′44
″Co
ulta
Grano
diorite
(∼25
20Ma)
120–
320μm
Colourless
1:4
Elon
gate,rectang
ular,e
uhed
ral,tabu
lar
grains
Largeco
resfree
from
zoning
surrou
ndingby
rimsof
oscilla
tory
zoning
.
MO7
136°
45′46
″–33
°29′
48″
Miltalie
Ortho
gneiss
(∼20
00Ma)
70–23
0μm
Colourless
1:3
Euhe
dral
rang
ingbe
twee
ntabu
laran
dne
edle
likesh
ape
Zircon
srang
ebe
twee
nlargeco
reswithminor
overgrow
thrimsto
smallc
ores
with
major
oscilla
tory
overgrow
thswithsomediffus
ean
dmetam
ictfeatures
MS
136°
46′38
″–33
°33
′06
″Miltalie
Compo
site
(unc
onsolid
ated
sedimen
ts)
80–30
0μm
Redto
yello
wto
colourless
1:3
Roun
dedto
Euhe
dral
inex
tern
alform
with
mainlytabu
larbu
tsomene
edle
likein
shap
eZircon
sva
ryingwidelybe
twee
nab
sent
tooscilla
tory
zoning
.Ofthezo
nedzircon
sco
resap
pear
tobe
med
ium
insize
withnu
merou
sdiffus
ean
dmetam
ictde
fects
136°
45′58
″–33
°28
′22
″
136°
43′03
″–33
°19
′50
″
136°
43′02
″–33
°19
′57
″
-20-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
-21-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
4.3. Sm–Nd isotopic results
Sm–Nd isotopic results for 11 samples from the Corny PointParagneiss and 3 samples from the Miltalie Gneiss are shown inTable 3. The Corny Point Paragneiss samples range in εNd (1850) from−4.6 to −0.8 with an average of −3.6±0.1. The Miltalie Gneisssamples range in εNd (1850) from −1.6 to −0.8.
4.4. Zircon Hf isotopic results
Hf isotopic results for all samples used in this study are available inthe electronic supplement and are presented comparatively in Fig. 3on an εHf vs. time plot. Of the 58 zircons from the Corny PointParagneiss analysed for Hf isotopes, only 43 were used, limited byb10% age discordancy. These points plot mainly between the CHURand the depleted mantle (Fig. 3).
Hf isotopic data was also collected for the Miltalie Gneiss and theCoulta Granodiorite. Additionally to aid in exploring the provenance ofthe protoliths of the Corny Point Paragneiss, a ca 2000 Ma volcani-clastic package (theWildman Siltstone) from the Pine Creek Orogen inthe North Australian Craton (Worden et al., 2008) was also analysed.All sixteen of the Miltalie Orthogneiss Hf isotopic results were used asthey were within 10% of age concordancy. The Miltalie Orthogneissplots in a small group with εHf values between −2 and −5 at 2000–2020 Ma, suggesting little similarity with similarly-aged detritalzircons in the Corny Point Paragneiss. The composite Miltaliesediment sample supports these results, overlapping with the MiltalieOrthogneiss rock sample data (Fig. 3). Of the 17 zircons analysed for Hfisotopes from the Coulta Granodiorite, 13 were used as they werewithin 10% of age concordancy. The zircons from the CoultaGranodiorite have εHf values between +1 and+4 at 2520–2550 Ma(Fig. 3).
The U–Pb zircon dates for the ca 2000 Ma volcaniclastic WildmanSiltstone from the Pine Creek Orogen in the North Australian Cratonwere obtained from Worden et al. (2008). The Hf isotopic data wereobtained from the same grain mount and age analysis spots used byWorden et al. (2008). These zircons have positive εHf values between+2 and +8 at 2000–2020 Ma.
Crustal model ages (TDMc ) were calculated for each zircon assumingaverage continental crust with 176Lu/177Hf values of 0.0015 (Griffin etal., 2002) as the zircon grain growth reservoir. Based on this crustalmodel, an age range of 2.79 to 2.94 Ga is obtained for the MiltalieGneiss. This is very similar to the crustal model age range of the CoultaGranodiorite (2.76 to 2.95 Ga). The Corny Point Paragneiss has a
younger crustal model age range of 2.30 to 2.55 Ga which overlapswith the range of the ca 2000 MaWildman Siltstone (2.23 to 2.65 Ga).
5. Discussion
5.1. Corny Point Paragneiss — depositional age constraints
Given the similarity in age peaks and close proximity in outcrop,the three Corny Point Paragneiss samples used for U–Pb zircon datingare grouped together for the purpose of discussion (Fig. 4). Theyoungest analysed zircon with interpreted detrital characteristicsyields an age of 1852±18 Ma. This is within error of the intrusive ageof the Donington Suite (Reid et al., 2007) which intrudes the CornyPoint Paragneiss (Reid et al., 2008). However, the age of this singlezircon grain is isolated from a larger group of slightly older detritalzircon grains which give ages around 1870–1880 Ma, followed by acontinuum ranging up to around 2050–2090 Ma. We suggest that this1870–1880 Ma peak provides a realistic maximum depositional age,suggesting that the protoliths to the metasedimentary rocks weredeposited in the interval 1870–1850 Ma.
5.2. Correlation of detrital zircon ages with a potential source region
U–Pb zircon ages from the metasedimentary units are displayed ascomparative probability density plots in Fig. 5. Age population peaksfound within the metasedimentary rocks occur at 1900 Ma, 2000 Ma,2450Ma, and 2510Ma. A suitable source regionwould need to containthese same zircon age populations to be considered viable. The seriesof ages can be considered as a diagnostic pattern for the source of themetasedimentary sequence.
For the purpose of this study, the most obvious potential source toconsider is the N1850 Ma components of the Gawler Craton whichoutcrop to the west of the metasedimentary package (Fig. 1). Fig. 5summarises all the zircon grain ages from N1850 Ma rocks availablefrom the Gawler Craton (Jagodzinski, 2005; Swain et al., 2005;Jagodzinski et al., 2006; Fanning et al., 2007). Three Gawler Cratontime lines associated with zircon growth occur across the numeroussamples represented in Fig. 5: the Dutton Suite (2510–2530 Ma), theSleafordian Orogeny (2420–2480 Ma) and the Miltalie Event (2000–2025 Ma) (Daly et al., 1998; Swain et al., 2005; Fanning et al., 2007;Hand et al., 2007). To supplement this data set, several samples fromthe Gawler Craton that coincide with two of the dominant detritalzircon ages found in the Corny Point Paragneiss were analysed as apart of this study (Fig. 5). These include the 2520 Ma Coulta
Fig. 2. U–Pb concordia plots for samples from the Corny Point Paragneiss, Coulta Granodiorite, Miltalie Orthogneiss and Miltalie Composite with inset probability density plots. Alldata are displayed in the concordia plots, including discordant grains. The probability density plots show 207Pb/206Pb ages with b10% discordant grain peaks in black and all data ingrey. Data-point error ellipses are at the 68.3% confidence interval.
Table 3Results of Sm–Nd isotopic analysis.
Sample no. Location Rock type Sm (ppm) Nd (ppm) 147Sm/144Nd 143Nd/144Nd 2 S.E. εNd (0) εNd (T) TDM (Ma)
CP8 137° 01′ 05″ –34° 53′ 45″ Corny Point Paragneiss (∼1850 Ma) 6.8297 37.3216 0.1107 0.511389 10 −24.4 −4.0 2572CP5 137° 01′ 03″ –34° 53′ 46″ Corny Point Paragneiss (∼1850 Ma) 9.1768 52.4062 0.1058 0.511346 8 −25.2 −3.7 2518CP-2006-23 137° 00′ 57″ –34° 53′ 37″ Corny Point Paragneiss (∼1850 Ma) 7.7677 44.6904 0.1050 0.511483 10 −22.5 −0.8 2312CP-2006-18 137° 00′ 53″ –34° 53′ 36″ Corny Point Paragneiss (∼1850 Ma) 9.4417 47.7419 0.1195 0.511464 8 −22.9 −4.6 2690CP-2006-12 137° 00′ 51″ –34° 53′ 40″ Corny Point Paragneiss (∼1850 Ma) 6.1177 35.9253 0.1029 0.511329 11 −25.5 −3.3 2475CP-2006-11 137° 00′ 51″ –34° 53′ 40″ Corny Point Paragneiss (∼1850 Ma) 8.2414 47.2593 0.1054 0.511337 8 −25.4 −3.7 2519CP-2006-10 137° 00′ 51″ –34° 53′ 40″ Corny Point Paragneiss (∼1850 Ma) 8.2822 47.6594 0.1050 0.511339 9 −25.3 −3.6 2509CP-2006-09 137° 01′ 05″ –34° 53′ 45″ Corny Point Paragneiss (∼1850 Ma) 12.8664 71.4970 0.1088 0.511375 8 −24.6 −3.8 2546CP-2006-07 137° 01′ 05″ –34° 53′ 45″ Corny Point Paragneiss (∼1850 Ma) 10.8773 60.4778 0.1087 0.511357 8 −25.0 −4.1 2570CP-2006-05 137° 01′ 05″ –34° 53′ 45″ Corny Point Paragneiss (∼1850 Ma) 11.2325 63.6159 0.1067 0.511329 10 −25.5 −4.2 2561CP-2006-02 137° 01′ 05″ –34° 53′ 45″ Corny Point Paragneiss (∼1850 Ma) 5.7722 32.4827 0.1074 0.511385 10 −24.4 −3.3 25007D 136° 45′ 46″ –33° 29′ 48″ Miltalie Orthogneiss (∼2000 Ma) 12.5240 73.4780 0.1030 0.511314 16 −25.8 −1.6 229611B 136° 43′ 03″ –33° 19′ 50″ Miltalie Orthogneiss (∼2000 Ma) 22.6219 132.8884 0.1029 0.511353 8 −25.1 −0.8 224011C 136° 43′ 03″ –33° 19′ 50″ Miltalie Orthogneiss (∼2000 Ma) 11.4065 65.8970 0.1046 0.511368 10 −24.8 −0.9 2257
-22-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
Granodiorite in the Dutton Suite, and the 2000 Ma protoliths to theMiltalie Gneiss rock suites of the Gawler Craton.
Further evidence supporting the dominant Gawler Craton time-lines of 2000Ma, 2450Ma, and 2520Ma, comes from a Terranechron®
dataset (Belousova et al., 2006) (Fig. 5). This data was acquired byanalysing detrital zircons in modern day stream sediment derivedfrom erosion of the present day exposed Gawler Craton. Fig. 5 showsthat the dominant ages of zircons currently being eroded matcheswith the detrital zircon ages within the Corny Point Paragneiss.
Therefore, erosion of N1850 Ma components of the Gawler Craton,at least as now presently exposed, would have provided detritalzircons of ages 2000 Ma, 2450Ma and 2520Ma. However, conceivablythis spectrum of ages may not have been available for erosion at ca1870–1850 Ma, which corresponds to the depositional age range ofthe Corny Point Paragneiss Protoliths. The ability of the Gawler Cratonto provide the range of above detrital zircon ages prior to 1850 Maappears to be confirmed by detrital zircon ages in the WarrowQuartzite (Fanning et al., 2007), which forms an extensive sequencethat directly overlies ca 2520–2000 Ma rocks of the Gawler Craton(Daly et al., 1998; Hand et al., 2007). Nd isotope data from theWarrowQuartzite (Fig. 6) shows a similar isotopic composition to thatexpected from erosion of the underlying rocks in the eastern GawlerCraton (Schwarz et al., 2002). Based on this logic, the detrital zirconages of 2000, 2450 and 2520 Ma found in the Warrow Quartzite(Fig. 5) are considered to be representative of ca 1870–1850 Maerosion of the Gawler Craton.
There are a number of recent examples where correspondencesbetween a series of detrital zircon ages and zircon growth events inpotential source regions have been used as either the sole or mostconstraining basis for interpreted palaeogeographic connectionbetween either source to sediment or sediment to sediment links(e.g. Dickinson and Gehrels, 2003; Friend et al., 2003; Gillis et al.,2005; Samson et al., 2005; Talavera-Mendoza et al., 2005; Carter et al.,2006; Darby and Gehrels, 2006; Gleason et al., 2007; Kirkland et al.,2007). Given the correspondence between the ages of detrital zirconsin the Corny Point Paragneiss and the major intervals of zircon growth
in N1850 Ma rocks in the adjacent Gawler Craton, a reasonableinterpretation would be that the protoliths to the Corny PointParagneiss were derived from erosion of pre 1850 Ma rocks in theGawler Craton.
5.3. Correlation of isotopic data with a potential source region
To examine whether the age correspondence between detritalzircons in the Corny Point Paragneiss and N1850 Ma zircon formingevents in the Gawler Craton is significant in terms of identifying thesource region to the metasedimentary rocks, bulk rock Nd and zirconHf isotopic data are used to provide additional constraints. If the CornyPoint Paragneiss protoliths were derived from the adjacent GawlerCraton, then Sm–Nd isotopic data and Hf zircon isotopic compositionsbetween the two regions should correspond.
Existing Nd data from the average late Archaean Gawler Cratonshows that it has a crustally evolved isotopic signaturewith εNd (1850 Ma)
values ranging between −11 and −7 (Stewart, 1992; Turner et al.,1993; Creaser, 1995; Swain et al., 2005; Schaefer, 1998) (Fig. 6). Dueto the significant 2000 Ma detrital zircon age peak in themetasedimentary rocks (Fig. 5), additional Nd isotopic data wascollected from the 2000 Ma Miltalie Gneiss in the adjacent GawlerCraton to supplement existing data. εNd (1850 Ma) values rangebetween −5 and −3 for these rocks. Nd isotopic data from theoverlying 2000–1850 Ma Warrow Quartzite, which overlies theMiltalie Gneiss and contains detrital zircon age peaks of 2000 Ma,2450 Ma and 2520 Ma (Fig. 5), has εNd (1850 Ma) values rangingbetween−10 and−7 (Schwarz et al., 2002). This range is consistentwith the average for the underlying eastern Gawler Craton basement,suggesting that the Warrow Quartzite was derived from erosion ofthe Gawler Craton. If this conclusion is valid, it implies that ca 1870–1850 Ma erosion of the Gawler Craton would have produced detritalzircon age populations of 2520, 2450 and 2000 Ma, which areessentially identical to those found in the Corny Point Paragneiss.
Since the Gawler Craton seems a likely source region for the1850 Ma metasedimentary units based on comparative zircon ages,
Fig. 3. εHf values plotted against 207Pb/206Pb ages for individual zircon grains from the Corny Point Paragneiss, Miltalie Gneiss, Coulta Granodiorite and the Gawler Craton. The GawlerCraton data are from Belousova et al. (2006). Discordant grains (N10%) have been omitted. Vertical lines represent the timing of dominant zircon age populations; 1990–2020 Ma,2420–2450 Ma and 2500–2530 Ma.
-23-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
εNd values expected for the Corny Point Paragneiss should involve amixture of comparatively juvenile material from the Miltalie Gneissand crustally evolved material from the average Archaean GawlerCraton. Thus εNd (1850 Ma) values of between −10 to −6 could bepredicted for the Corny Point Paragneiss.
However, εNd (1850 Ma) values of between−5 to−1 from the CornyPoint Paragneiss suggests derivation from a more juvenile source thanthe average Archaean Gawler Craton. Within the context of sedimentderivation from the Gawler Craton, one explanation for the differentNd isotopic compositions is that significant input from comparatively
more juvenile sources such as the Miltalie Gneiss mixed with smalleramounts of average Archaean Gawler Craton, allowing the overallisotopic signature to remain relatively juvenile. However, the propor-tion of ca 2450–2520 Ma detrital grains suggests that a significantcomponent of the detritus was derived from pre-2000 Ma rocks.Another explanation is that the Gawler Craton could have included arock system that has since eroded away which could have suppliedmore juvenile sediment input. This is a distinct possibility for theproto Gawler Craton, since the granulite facies Miltalie Gneiss wasexposed by ca 1850Ma (Daly et al., 1998; Hand et al., 2007), indicatingsignificant levels of Palaeoproterozoic denudation in the GawlerCraton. However, the crustally evolved isotopic composition of theWarrow Quartzite, which directly overlies the ca 2000 Ma rocks in theGawler Craton suggest that Palaeoproterozoic erosion of the GawlerCraton would have produced crustally evolved detritus. Therefore itappears that the Corny Point Paragneiss and Warrow Quartzite mayhave been derived from terrains with similar aged rock systems, butwith different crustal evolutions.
Hf isotopic data offer further insight into testing the validity of aGawler Craton source for the metasedimentary rocks. εHf data fromGawler Craton samples including theMiltalie Orthogneiss, theMiltaliecomposite sample, and the Coulta Granodiorite are displayed in Fig. 3.
The time interval 2510–2530 Ma corresponds with the oldestmajor peak in the Corny Point Paragneiss as well as a major rockforming period in the Gawler Craton. At this time period Hf isotopesare less useful than younger time slices in determining crustalevolution between zircon populations from different source regions.This is due to two effects: 1) the evolution pathways of crustalvolumes converge back through time toward the depleted mantle;and 2) the scale of the errors on the Hf isotope data. Therefore theisotopic distinction between juvenile and reworked crust is not asdefinitive as for younger periods of Earth history. Regardless, it is stillevident that the ca 2520 Ma Coulta Granodiorite has zircon εHf (2520 Ma)
values ranging from+1 to+4 (Fig. 3) and sitswithin the range of the ca2520–2450 Ma Sleafordian Complex in the Gawler Craton representedby Terranechron® and rock data (Belousova et al., 2006).
Within the ca 2000 Ma interval, the zircons of the Miltalie Gneisshave crustally evolved εHf values ranging from −2 to −5 (Fig. 3). Acompilation of available εHf data from ca 2000 Ma zircons in theGawler Craton (Belousova et al., 2006; Fig. 3), show identical isotopicsignatures, and are probably derived from the Miltalie Gneiss and itsequivalents. This emphasises the comparatively crustally evolvednature of the 2000 Ma zircons within the Gawler Craton. Similaritiesbetween the compiled data (Belousova et al., 2006) and the Miltaliesamples analysed in this study suggest the samples used here arerepresentative of the Miltalie system at a larger scale.
Therefore zircons being eroded from the Gawler Craton wouldshow isotopic signatures with εHf (2520 Ma) values ranging from−2 to+5, and εHf (2000 Ma) values ranging from −2 to −5. If the GawlerCraton was the source region for the Corny Point Paragneiss then thezircons between them should have the same isotopic compositions.
The isotopic composition of the zircons in the 2520 Ma age groupfrom the Corny Point Paragneiss falls within the range of values fromthe Gawler Craton. However, the 2000 Ma detrital zircons from themetasedimentary rocks are too juvenile with εHf (2000 Ma) values of+2to +5. It therefore appears on the basis of Hf isotopic data thatequivalents of the presently exposed Gawler Craton were not thesource of the 2000 Ma detrital zircons in the Corny Point Paragneiss.
Hf isotopic crustal model ages further support this argument(Fig. 3). The crustal model age range for the 2000 Ma zircons from theMiltalie Gneiss and the 2000 Ma zircons from the Gawler CratonTerranechron® is 2.94 Ga to 2.79 Ga, which is identical to that of the2520 Ma Coulta Granodiorite (Fig. 3) suggesting the 2000 Ma zirconswithin the Miltalie Gneiss were formed from reworking of materialisotopically similar to the Coulta Granodiorite. The crustal model agerange of the zircons within the Corny Point Paragneiss is much
Fig. 4. U–Pb zircon probability density plots showing 207Pb/206Pb ages with b10%discordant analyses for the three individual Corny Point Paragneiss samples and acombined probability density plot.
-24-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
younger at 2.30 Ga to 2.55 Ga. This further supports the proposal thatequivalents of the presently exposed Gawler Craton were not thesource of the Corny Point Paragneiss. This conclusion is consistentwith the comparative Nd isotopic compositions of the pre-1850 MaGawler Craton and the Corny Point metasedimentary rocks.
5.4. Other potential source regions for the Corny Point Paragneiss Protoliths
Since derivation of the Corny Point Paragneiss protoliths from theadjacent Gawler Craton appears unlikely despite the good correspon-dence between detrital zircon ages and zircon growth events on thecraton, the source region is unknown. At present our understanding ofthe arrangement of the continents at 1850 Ma is poor (Dawson et al.,2002; Betts and Giles, 2006; Payne et al., 2008; Betts et al., 2008),therefore in searching for the source of the Corny Point Paragneissprotoliths consideration should be given to any region that satisfiesthe U–Pb zircon ages, whole rock Nd and zircon Hf isotopic data.
Withinpresent dayAustralia there are fewknown∼2000Ma zirconbearing rocks systems. In the North Australia Craton, the Pine CreekOrogen (Fig. 7) contains a ca 2000 Ma volcaniclastic (Worden et al.,2008). In theWestern Australian Craton, theGlenburghOrogen (Fig. 7)contains ca 2000 Ma granites (Sheppard et al., 2004). Whole rock Ndisotopic data from the 2000 Ma magmatic rocks in the GlenburghOrogen range from εNd (2000 Ma) −8 to −3 (Sheppard et al., 2004)which is more evolved than the range of the Corny Point Paragneiss.While there is no available Hf isotopic data for these 2000 Mamagmatic rocks, using the calculations determined for the terrestrialHf–Nd array (εHf=1.36 εHf+2.95; Vervoort et al., 1999) whole rockεHf (2000 Ma) values of −2 to −8 can be estimated. Although this is abulk rock estimate, it suggests that the c. 2000 Ma granites of theGlenburgh Orogenwould have been too evolved to have generated theHf isotopic compositions (εHf (2000 Ma) range of +2 to +5) of thesimilarly aged zircons in the Corny Point Paragneiss. Thus it appearsthat the Glenburgh Orogen is an unlikely source region.
The Pine Creek Orogen in the North Australian Craton (Fig. 7) hasat least four major rock forming timelines in commonwith the GawlerCraton, suggesting it could be plausibly linked with the Gawler Craton(Table 4). At ca 2520 Ma, granitic rocks of the Gawler Craton (Swainet al., 2005; Fanning et al., 2007; this study) are comparable in age tothe 2520–2450 Rum Jungle Complex in the Pine Creek Orogen (Crosset al., 2005). Sleafordian metamorphism (2480–2420 Ma) in theGawler Craton (Swain et al., 2005; Hand et al., 2007) is roughlysynchronous with 2470 Ma granite emplacement in the NanambuComplex of the Pine Creek Orogen (Page et al., 1980). The 2000–
Fig. 6. εNd vs. time diagram for the Corny Point Paragneiss, Miltalie Gneiss and theWarrow Quartzite (Schwarz et al., 2002). Average Gawler Craton is calculated frompublished data for currently exposed lithologies N1850 Ma, (Turner et al., 1993; Creaser,1995; Swain et al., 2005; Schaefer, 1998; Stewart, 1992). The depositional age of theWarrow Quartzite is poorly constrained to the interval 2000–1850 Ma (Hand et al.,2007). Data are plotted at 1850 Ma; however, the white band represents the isotopicevolutionary trend back to 2000 Ma.
Fig. 5. U–Pb zircon probability density plot showing207
Pb/206
Pb zircon ages of samplesfrom the Corny Point Paragneiss, the Gawler Craton, the Gawler Craton Terranechron
®, and
theWarrowQuartzite. TheGawlerCraton compilation isderived fromSHRIMPzircongrainsolder than 1840 Ma dated from the Gawler Craton (Jagodzinski, 2005; Swain et al., 2005;Jagodzinski et al., 2006; Fanning et al., 2007). TheGawler Craton Terranechron
®probability
density plot is derived from LA-ICPMS analyses of zircon grains older than 1840 Ma fromBelousova et al. (2006). TheWarrow Quartzite data are from Fanning et al. (2007), and aretaken to represent erosion of the Gawler Craton in the interval 2000–1850Ma (see text fordetails). Grey bands reflect the dominant detrital zircon age peaks of the Corny PointMetasedimentary rocks. Only b10% discordant analyses have been included.
-25-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
2020 Ma time period is represented by the Miltalie Gneiss in theGawler Craton (Fanning et al., 2007; this study), and the tuffaceousWildman Siltstone in the Pine Creek Orogen (Worden et al., 2008).The 1857–1850 Ma Donington Suite and related metamorphism (Reidet al., 2008) is coeval with the 1850–1840 Ma granites in the westernPine Creek Orogen (Page et al., 1985) and 1861–1847 Ma metamorph-ism of the Nimbuwah event (Carson et al., 2008; Worden et al., 2008).
As there are no previous isotopic data for the ca 2000 Ma rocksfrom the Pine Creek Orogen, Hf isotopic datawere collected for zirconsfrom the 2020 Ma Wildman Siltstone (Fig. 3) to compare with the ca2000–2020Ma zircons in the Corny Point Paragneiss. The zircons from
the Wildman Siltstone sample gave an εHf (∼2000 Ma) range of between+7 and −1, which overlaps with the isotopic compositions of the ca2020 Ma zircons from the Corny Point Paragneiss (+2 to +5).Similarly, crustal model ages for the zircons from the WildmanSiltstone range from 2.23 Ga to 2.65 Ga encompassing the crustalmodel age range for the ca 2000 Ma zircons from the Corny PointParagneiss (2.30 Ga to 2.55 Ga; Fig. 3). Thus it is clear that erosionfrom equivalents of the presently exposed Pine Creek Orogen of theNorth Australian Craton could have provided zircons with agescorresponding to the three dominant timelines of 2000–2020 Ma,2420–2450Ma and 2520–2540Ma found in the detrital zircon spectra
Fig. 7. Map of Australia showing the three potential Australian source regions for the Corny Point Paragneiss based on the presence of 2020 Ma zircons; (1) the Glenburgh Orogenwithin the Gascoyne Complex of theWest Australian Craton, (2) theWildman Siltstone within the Pine Creek Inlier of the North Australian Craton, (3) the Miltalie Orthogneiss of theGawler Craton.
Table 4
Gawler Craton Pine Creek Orogen
2545–2520 Ma magmatism 2520 Ma granite emplacement e.g. Glenloth Granite and Coulta Granodiorite(Daly and Fanning, 1993)
2545–2520 Ma granites emplacement — Rum Jungle Complex(Cross et al., 2005)
2545–2480 Ma deposition 2535–2480 Ma sediment deposition e.g. Christie Gneiss and Kenella Paragneiss(Daly et al., 1998; Swain et al., 2005)
2545–2520 Ma sediment deposition — Stanley Metamorphics(Cross et al., 2005)
2480–2420 Ma 2480–2420 Ma metamorphism — Sleafordian Orogeny (Daly and Fanning, 1993;Daly et al., 1998)
2470 Ma granite emplacement — Nanambu Complex(Page et al., 1980)
2000–2020 Ma 2020 Ma magmatism — Miltalie Orthogneiss (Fanning et al., 1988) 2020 Ma deposition of tuffaceous Wildman Siltstone 2020 Ma(Worden et al., 2008)
∼1850 Ma magmatism 1850 Ma granite emplacement — Donington Suite (Reid et al., 2008) 1850–1840 Ma granite emplacement in Litchfield Province(Page et al., 1985)
∼1850 Ma metamorphism 1850 Ma metamorphism —Cornian Orogeny (Reid et al., 2008) 1861–1847 Ma metamorphism — Nimbuwah event(Carson et al., 2008)
-26-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
in the Corny Point Paragneiss. Additionally, the Pine Creek Orogen couldalso have provided2000Ma zirconswith similarHf isotopic compositionsto the2000Mazircons in theCornyPoint Paragneiss in theGawler Craton.
Provenance studies cannot prove a source-sediment connection;they can only disprove it. At this stage the data suggest that the PineCreek Orogen in the North Australian Craton is a plausible sourceregion. However, given the antiquity of the rocks, there is nocompelling reason why the source region is still located in presentday Australia.
Globally the ca 2000 Ma zircons within the Corny Point Paragneisswould appear to limit the worldwide search for a source region to anumber of Palaeoproterozoic terrains which are listed in Table 5.Zircon forming events including magmatism and metamorphismdated at around 2000 Ma have been reported from the North ChinaCraton (Liu et al., 2002; Zhao et al., 2002), the Amazonian Craton (daRosa-Costa et al., 2006), the Brazilian Shield (Hartmann et al., 2003),the East African Craton (Moller et al., 1995; Ring et al., 1997; Collinset al., 2004), the Limpopo Belt (Jaeckel et al., 1997; Kroner et al., 1998;McCourt and Armstrong, 1998; Mapeo et al., 2001; Mapeo et al., 2004;Buick et al., 2006; Dorland et al., 2006; Zeh et al., 2007), the NorthernGreenland Shield (Nutman et al., 2008) and the Rinkian Belt (Kalsbeeket al., 1998; van Gool et al., 2002).
Potentially any of these regions could have provided detrital inputsinto the Corny Point Paragneiss protoliths. Several of these regionscontain other zircon growth time lines that approximately match theages of detrital zircons in the Corny Point Paragneiss. However asdemonstrated above, additional isotopic constraints are requiredbefore any source region is considered viable and in many instancesthere is insufficient isotopic data to refine the list of potential sourceregions shown in Table 5.
5.5. Limitations of provenance as a palaeogeographic tool
Aside from the use of supplementary isotopic data sets to examinethe veracity of interpretations based on age alone, it is worthexploring the limitations of provenance as a tool to constrainpalaeogeography, particularly in the context of the available samplesof N1850 Ma rocks in the south eastern Gawler Craton. Connectionbetween a potential source region and a depositional location can onlybe established if: (a) the source region in question was exposed andundergoing erosion; and (b) a sediment transport system connectedthe two regions. Ideally, sampling of sequences for provenance shouldinvolve a number of different stratigraphic positions to minimisetransient effects such as minor topographic diversion of transportsystems. However, in the case of the sampled sequences in the southeastern Gawler Craton, there is little constraint on the extent ofstratigraphic separation between samples. Additionally, even long-lived sediment transport systemsmay not adequately represent majorrock forming times in the adjacent regions.
An example of the latter scenario is seen today in the Palaeozoic–recent Perth Basin bordering the Yilgarn Craton in western Australia(Fig. 8). Despite their proximity to the Archaean Yilgarn Craton, theQuaternary sediments in the Perth Basin contain a minimal component(4.8% to 11.1%) of Archaean zircons even though the Yilgarn Cratonborders the basins for much of their length, and in places forms presentday escarpments flanking the basin (Sircombe and Freeman, 1999).Given its proximity to the Yilgarn Craton, many previous workers hadassumed that theQuaternarycoastal sandswerederived from its erosion(Baxter, 1977; Harrison, 1990; Shepherd, 1990). Instead, the majority ofzircon grains are Phanerozoic, Neoproterozoic and Mesoproterozoic inage (Sircombe and Freeman, 1999), and can be accounted for by
Table 5ca 2000 Ma high temperature rock systems.
Region Tectonic belt orgeological unit
Analytical method(SHRIMP U–Pbzircon unlessotherwise stated)
Age (Ma) Interpretation εNd (t) ZirconεHf (t)
Timing of other majorN1850 Ma zircon growthevents (Ga)
Reference
Magmatic Metamorphic
North ChinaCraton
Fuping Complex 2024±21 Magmatism −2.6 to−4.6 2.7, 2.52–2.49 1.88–1.8 (Zhao et al., 2002;Liu et al., 2002)
AmazonianCraton
Jari Domain Pb–Pb zirconevaporation
2030±2 Magmatism −2.42 2.8–2.79, 2.66–2.6, 2.32–2.22,2.18–2.13
da Rosa-Costa et al.(2006)
BrazilianShield
Itapema Granite 2022±22 Magmatism 2.5, 2.16 2.7, 2.2 Hartmann et al.(2003)
East AfricanCraton
UsagaranOrogen
1999±1 Eclogitemetamorphism
2.7, 1.9, 1.88 Collins et al. (2004)
UsagaranOrogen
TIMS U–Pbmonazite, titanite
∼2010 Eclogitemetamorphism
Moller et al. (1995)
Ubendi Orogen Pb–Pb zirconevaporation
1988–2002 Magmatismandmetamorphism
Ring et al. (1997)
Limpopo Belt MahalapyeComplex
LA-ICPMS zircon 2019±8 Magmatism −11.3 to−20.1
3.28, 2.71, 2.65,2.61, 2.06
3.2–3.1,2.65–2.52,2.02–2.04
(Zeh et al., 2007;McCourt andArmstrong 1998;
Palapye Group 2034±8 Inheritance Mapeo et al., 2004)Beit BridgeComplex
Pb–Pb zirconevaporation
2023±12,2027±6,2006±4
MagmatismandMetamorphism
(Kroner et al., 1998;Jaeckel et al., 1997)
Central zone SHRIMP U–Pbmonazite
2028±3 Metamorphism Buick et al. (2006)
The EntabeniGranite
2021±5 Magmatism Dorland et al. (2006)
Magondi Belt 2027±8 Metamorphism Mapeo et al. (2001)Northern GreenlandShield
Etah Group(1980)a
1980–2000 Detrital zirconage peak
−3 and +3 3.4, 2.6, 1.98,1.94–1.91,
1.92 Nutman et al.(2008)
Rinkian Belt Karrat Group,(2012–1850 Ma)a
2012±12 Detrital zirconage peak
−2.85 3.15, 2.87–2.7,2.5, 1.92–1.87,1.86–1.84
1.86–1.84 (Kalsbeek et al.,1998; van Gool et al.,2002)
a Maximum–minimum depositional age range.
-27-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
derivation from the Mesoproterozoic Albany Fraser Orogen and theNeoproterozoic Leeuwin Block with transportation via longshore drift.
The Perth Basin is separated from the Yilgarn Craton by thecrustal-scale Darling Fault which forms a basin bounding structure,but is not a suture between the Perth Basin and the Yilgarn Craton.Hypothetically in the future when the specific relationships betweenthe Yilgarn Craton, Perth Basin and Darling Fault may be obscured,the paucity of Yilgarn-derived Archaean zircons in the Perth Basin
could be used as an argument that the Darling Fault was a terrainboundary separating domains that contain contrasting zircon agepopulations.
In the eastern Gawler Craton, the ca 2520–2000 Ma domain of thecraton is separated from the 1870–1850 Ma Corny Point Paragneiss bythe crustal scale Kalinjala Shear Zone, whichwas amajor strike slip faultduring the1730–1700MaKimbanOrogeny (Vassallo andWilson, 2002).The tectonic significance of the shear zone is still not well understood.
Fig. 8.Map and locations and probability detrital plots of Quaternary sands sampled from the Perth Basin and positioned west of the Yilgarn Craton divided by the Darling Fault fromSircombe & Freeman (1999). Inset shows the location of the region within Australia.
NOTE: This figure is included on page 27 of the print copy of the thesis held in the University of Adelaide Library.
-28-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
Betts andGiles (2006) suggest that it represents a 1730–1700Ma suturealong which the 2520–2000 Ma domain in the Gawler Craton wasjuxtaposed against rocks to the east including the 1870–1850 Ma CornyPoint Paragneiss and the enclosing 1850 Ma intrusives. The apparentabsence of a Gawler Craton origin for the 1870–1850 Ma sequencesexamined in this study lends support to such a notion. However, as isclear with the example from the Perth Basin, the absence of zirconsderived from the Gawler Craton does not prove such a model,highlighting that for the most part provenance data can only be usedto preclude models rather than prove them.
6. Conclusion
Detrital zircon ages from the Corny Point Paragneiss in the southeastern Gawler Craton, Australia, coupled with post-depositionaltectonism, constrain sedimentation to the interval ca 1870–1850 Ma.The metasedimentary sequence contains detrital zircons age peaks at2000 Ma, 2450 Ma, and 2510 Ma which match the dominant zirconforming time lines from the immediately adjacent Gawler Craton,suggesting the craton was the source region. However, Nd and zirconHf isotopic data rule out equivalents of the presently exposed GawlerCraton as a dominant source region for the protoliths of the CornyPoint Paragneiss, despite the correspondence between zircon growthevents and detrital zircon ages. Instead, based on a combination of agegroups and comparative Hf isotopic compositions, a plausible (but byno means proven) source region is the Pine Creek Orogen in the farnorthern part of the North Australian Craton.
Detrital zircon dating alone in provenance studies is limiting, andcan lead to erroneous palaeogeographic interpretations. With theaddition of Nd and Hf zircon isotopic data, crustal evolution can becompared from individual zircon grains and on the whole rock scale.This combination of tools can enable more discriminating testing ofsource regions where a correspondence of ages exists betweensedimentary basins and their potential source, further enablingmore accurate palaeogeographic reconstructions.
Acknowledgements
We would like to acknowledge the Mineral Resources Group ofPrimary Industry Resources South Australia (PIRSA) for providingfinancial support for this project. Kurt Worden from GeoscienceAustralia is acknowledged for providing age data, images and thezircon mount from the Wildman Siltstone. The authors would like tothank Justin Payne for the analytical support and numerous discus-sions on isotope systematics and evolution of the Gawler Craton,Jonathan Patchett for comments on an earlier version of the manu-script and Michael Szpunar for a number of discussions about theevolution of the eastern Gawler Craton. Thanks are also given to DavidBruce for assistance with Sm–Nd analyses, and Angus Netting fromAdelaide Microscopy for assistance with zircon imaging and analysis.Lastly we would like to acknowledge journal reviewers Oliver Nebeland an anonymous reviewer for their helpful comments and sugges-tions, and Roberta Rudnick for comments and editorial handling of themanuscript. This work was supported by Australian Research CouncilGrant LP0454301.
Appendix A. Supplementary data
Supplementary data associated with this article can be found, inthe online version, at doi:10.1016/j.chemgeo.2009.01.029.
References
Amelin, Y., Lee, D.C., Halliday, A.N., 2000. Early-middle Archaean crustal evolutiondeduced from Lu–Hf and U–Pb isotopic studies of single zircon grains. GeochimicaEt Cosmochimica Acta 64 (24), 4205–4225.
Andersen, T., 2005. Detrital zircons as tracers of sedimentary provenance: limitingconditions from statistics and numerical simulation. Chemical Geology 216 (3–4),249–270.
Augustsson, C., Munker, C., Bahlburg, H., Fanning, C.M., 2006. Provenance of late Palaeozoicmetasediments of the SW South American Gondwana margin: a combined U–Pb andHf-isotope study of single detrital zircons. Journal of the Geological Society 163,983–995.
Banks, C.J., et al., 2007. Provenance of intra-Rodinian basin-fills: the Lower DalradianSupergroup, Scotland. Precambrian Research 153 (1–2), 46–64.
Barovich, K.M., Foden, J., 2000. A Neoproterozoic flood basalt province in southern-central Australia; geochemical and Nd isotope evidence from basin fill. PrecambrianResearch 100 (1–3), 213–234.
Baxter, J.L., 1977. Heavymineral sand deposits ofWestern Australia. Geological Survey ofWestern Australia Mineral Resources Bulletin 10, 148.
Belousova, E.A., Reid, A.J., Schwarz, M.P., Griffin, W.L., Fairclough, M.C., 2006. Crustalevolution of the Gawler Craton, South Australia: application of the TerraneChrontechnique to detrital zircon from modern stream sediments. South Australia.Department of Primary Industries and Resources. Report Book. 2006/4. http://www.pir.sa.gov.au/minerals/publications/gawler_releases.
Betts, P.G., Giles, D., 2006. The 1800–1100 Ma tectonic evolution of Australia. PrecambrianResearch 144 (1–2), 92–125.
Betts, P.G., Giles, D., Schaefer, B.F., 2008. Comparing 1800–1600 Ma accretionary andbasin processes in Australia and Laurentia: Possible geographic connections inColumbia. Precambrian Research 166 (1–4), 81–92.
Bizzarro, M., Baker, J.A., Haack, H., Ulfbeck, D., Rosing, M., 2003. Early history of Earth'scrust–mantle system inferred from hafnium isotopes in chondrites. Nature 421(6926), 931–933.
Blichert-Toft, J., Albarede, F., 1997. The Lu–Hf isotope geochemistry of chondrites and theevolution of the mantle–crust system. Earth and Planetary Science Letters 148 (1–2),243–258.
Buick, I.S., Hermann, J., Williams, I.S., Gibson, R.L., Rubatto, D., 2006. A SHRIMP U–Pb andLA-ICP-MS trace element study of the petrogenesis of garnet-cordierite-orthoam-phibole gneisses from the Central Zone of the Limpopo Belt, South Africa. ElsevierScience Bv, pp. 150–172.
Burrett, C., Berry, R., 2000. Proterozoic Australia–Western United States (AUSWUS) fitbetween Laurentia and Australia. Geology 28 (2), 103–106.
Carson, C.J., Worden, K.E., Scrimgeour, I.R., Stern, R.A., 2008. The Palaeoproterozoicevolution of the Litchfield Province, western Pine Creek Orogen, northern Australia:insight from SHRIMP U–Pb zircon and in situmonazite geochronology. PrecambrianResearch 166 (1–4), 145–167.
Carter, B.T.,Hibbard, J.P., Tubrett,M., Sylvester, P., 2006.Detrital zircongeochronologyof theSmith River Allochthon and Lynchburg Group, southern Appalachians: implicationsforNeoproterozoic–Early Cambrianpaleogeography. PrecambrianResearch147 (3–4),279–304.
Cawood, P.A., Nemchin, A.A., Freeman, M., Sircombe, K., 2003. Linking source andsedimentary basin: detrital zircon record of sedimentflux along amodern river systemand implications for provenance studies. Earth andPlanetary Science Letters 210 (1–2),259–268.
Cawood, P.A., Nemchin, A.A., Strachan, R., 2007. Provenance record of Laurentianpassive-margin strata in the northern Caledonides: implications for paleodrai-nage and paleogeography. Geological Society of America Bulletin 119 (7–8),993–1003.
Collins, A.S., Kroner, A., Fitzsimons, I.C.W., Razakamanana, T., 2003. Detrital footprintof the Mozambique ocean: U–Pb SHRIMP and Pb evaporation zircon geochronologyof metasedimentary gneisses in eastern Madagascar. Tectonophysics 375 (1–4),77–99.
Collins, A.S., Reddy, S.M., Buchan, C., Mruma, A., 2004. Temporal constraints onPalaeoproterozoic eclogite formation and exhumation (Usagaran Orogen, Tanzania).Earth and Planetary Science Letters 224 (1–2), 175–192.
Creaser, R.A.,1995.Neodymium isotopic constraints for the origin ofmesoproterozoic felsicmagmatism,Gawler-craton, SouthAustralia. Canadian Journal of EarthSciences32 (4),460–471.
Cross, A., Claoue-Long, J.C., Scrimgeour, I.R., Ahmad, M., Kruse, P.D., 2005. Summary ofresults. Joint NTGS-GA geochronology project: Rum Jungle, basement to southernGeorgina Basin and eastern Arunta Region 2001–2003. Northern Territory GeologicalSurvey Record 2005-006.
da Rosa-Costa, L.T., Lafon, J.M., Delor, C., 2006. Zircon geochronology and Sm–Ndisotopic study: further constraints for the Archean and Paleoproterozoic geodyna-mical evolution of the southeastern Guiana Shield, north of Amazonian Craton,Brazil. Gondwana Research 10 (3–4), 277–300.
Daly, S.J., Fanning, C.M., 1993. Archaean. In: Drexel, J.F., Preiss, W.V., Parker, A.J. (Eds.),The Geology of South Australia. The Precambrian, vol. 1. Geological Survey of SouthAustralia. Bulletin 54.
Daly, S.J., Fanning, C.M., Fairclough, M.C., 1998. Tectonic evolution and explorationpotential of the Gawler Craton, South Australia. AGSO Journal of Australian Geologyand Geophysics 17 (3), 145–168.
Darby, B.J., Gehrels, G., 2006. Detrital zircon reference for the North China block. Journalof Asian Earth Sciences 26 (6), 637–648.
Dawson, G.C., Krapez, B., Fletcher, I.R., McNaughton, N.J., Rasmussen, B., 2002. Did latePalaeoproterozoic assembly of proto-Australia involve collision between thePilbara, Yilgarn and Gawler cratons? Geochronological evidence from the MountBarren Group in the Albany–Fraser Orogen of Western Australia. PrecambrianResearch 118 (3–4), 195–220.
Dickinson, W.R., Gehrels, G.E., 2003. U–Pb ages of detrital zircons from Permian andJurassic eolian sandstones of the Colorado Plateau, USA: paleogeographic implica-tions. Sedimentary Geology 163 (1–2), 29–66.
-29-
Chapter 2 Detrital zircon ages: improving interpretati on via Nd and Hf isotopes
Shepherd, M.S., 1990. Eneabba heavymineral sand placers. In: Hughs, F.E. (Ed.), Geologyof the mineral deposits of Australia and Papua New Guinea. Australiasian Instituteof Mining and Metallurgy, Melbourne, pp. 1591–1594.
Sheppard, S., Occhipinti, S.A., Tyler, I.M., 2004. A 2005–1970 Ma Andean-type batholithin the southern Gascoyne Complex, Western Australia. Precambrian Research 128(3–4), 257–277.
Sircombe, K.N., Freeman, M.J., 1999. Provenance of detrital zircons on the WesternAustralia coastline — implications for the geologic history of the Perth basin anddenudation of the Yilgarn craton. Geology 27 (10), 879–882.
Soderlund, U., Patchett, J.P., Vervoort, J.D., Isachsen, C.E., 2004. The Lu-176 decayconstant determined by Lu–Hf and U–Pb isotope systematics of Precambrian maficintrusions. Earth and Planetary Science Letters 219 (3–4), 311–324.
Stewart, K.P., 1992. High temperature felsic volcanism and the role of mantle magmas inProterozoic crustal growth: The Gawler Range Volcanic Province. Ph.D thesis,University of Adelaide.
Swain, G., et al., 2005. Provenance and tectonic development of the late ArchaeanGawler Craton, Australia; U–Pb zircon, geochemical and Sm–Nd isotopic implica-tions. Precambrian Research 141 (3–4), 106–136.
Talavera-Mendoza, O., et al., 2005. U–Pb geochronology of the Acatlan Complex andimplications for the Paleozoic paleogeography and tectonic evolution of southernMexico. Earth and Planetary Science Letters 235 (3–4), 682–699.
Turner, S., Foden, J., Sandiford, M., Bruce, D., 1993. Sm–Nd isotopic evidence for theprovenance of sediments from the Adelaide Fold Belt and Southeastern Australiawith implications for episodic crustal addition. Geochimica Et Cosmochimica Acta57 (8), 1837–1856.
van Gool, J.A.M., Connelly, J.N., Marker, M., Mengel, F.C., 2002. The NagssugtoqidianOrogen of West Greenland: tectonic evolution and regional correlations from aWest Greenland perspective. Canadian Journal of Earth Sciences 39 (5), 665–686.
Vassallo, J.J., Wilson, C.J.L., 2002. Palaeoproterozoic regional-scale non-coaxial deforma-tion; an example from eastern Eyre Peninsula, South Australia. Journal of StructuralGeology 24 (1), 1–24.
Veevers, J.J., Saeed, A., Belousova, E.A., Griffin, W.L., 2005. U–Pb ages and sourcecomposition by Hf-isotope and trace-element analysis of detrital zircons in Permiansandstone and modem sand from southwestern Australia and a review of thepaleogeographical and denudational history of the Yilgam Craton. Earth-ScienceReviews 68 (3–4), 245–279.
Veevers, J.J., et al., 2006. Pan-Gondwanalanddetrital zircons fromAustralia analysed forHf-isotopes and trace elements reflect an ice-covered Antarctic provenance of 700–
500Ma age, T-DM of 2.0–1.0 Ga, and alkaline affinity. Earth-Science Reviews 76 (3–4),135–174.
Vervoort, J.D., Patchett, P.J., Blichert-Toft, J., Albarede, F., 1999. Relationships betweenLu–Hf and Sm–Nd isotopic systems in the global sedimentary system. Earth andPlanetary Science Letters 168 (1–2), 79–99.
Wade, B.P., Hand, M., Barovich, K.M., 2005. Nd isotopic and geochemical constraints onprovenance of sedimentary rocks in the eastern Officer Basin, Australia: implica-tions for the duration of the intracratonic Petermann Orogeny. Journal of theGeological Society 162, 513–530.
Wade, B.P., Hand, M., Maidment, D.W., Close, D.F., Scrimgeour, I.R., 2008a. Origin ofmetasedimentary and igneous rocks from the Entia Dome, eastern Arunta region,central Australia: a U‐Pb LA-ICPMS, SHRIMP and Sm–Nd isotope study. Taylor &Francis, pp. 703–719.
Wade, B.P., Kelsey, D.E., Hand, M., Barovich, K.M., 2008b. The Musgrave Province:Stitching north, west and south Australia. Precambrian Research 166 (1–4),370–386.
Wingate, M.T.D., Pisarevsky, S.A., Evans, D.A.D., 2002. Rodinia connections betweenAustralia and Laurentia: no SWEAT, no AUSWUS? Terra Nova 14 (2), 121–128.
Worden, K., Carson, C., Scrimgeour, I., Lally, J., Doyle, N., 2008. A revised Palaeoproter-ozoic chronostratigraphy for the Pine Creek Orogen, northern Australia: evidencefrom SHRIMP U–Pb zircon geochronology. Precambrian Research 166 (1–4),122–144.
Yang, J.H., et al., 2006. Constraints on the timing of uplift of the Yanshan Fold and ThrustBelt, North China. Earth and Planetary Science Letters 246 (3–4), 336–352.
Zang, W., 2002. Interpretation of the middle Palaeoproterozoic granites and gneisses(Lincoln Complex), southern Yorke Peninsula, South Australia. Department ofPrimary Industry Resources. Report Book, 2002/17.
Zeh, A., Gerdes, A., Klemd, R., Barton, J.M., 2007. Archaean to Proterozoic Crustalevolution in the Central Zone of the Limpopo Belt (South Africa–Botswana):constraints from combined U–Pb and Lu–Hf isotope analyses of zircon. Journal ofPetrology 48 (8), 1605–1639.
Zhao, G.C., Wilde, S.A., Cawood, P.A., Sun, M., 2002. SHRIMP U–Pb zircon ages of theFuping Complex: implications for late Archean to Paleoproterozoic accretion andassembly of the North China Craton. American Journal of Science 302 (3), 191–226.
-30-
Chapter 2 Supplementary MaterialSu
pple
men
tary
Tab
le A
.LA
-IC
PMS
zirc
on U
-Pb
isot
opic
dat
a fo
r all
sam
ples
Rat
ios
App
aren
t age
s (M
a)Sp
ot20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
Con
Cor
ny P
oint
Par
agne
iss C
P5
Z10.
2080
00.
0021
12.7
2478
0.15
040.
4437
70.
0054
0.09
057
0.00
0728
9016
2660
1123
6824
1753
1482
Z20.
1284
60.
0014
6.29
021
0.07
870.
3552
00.
0044
0.09
025
0.00
0920
7718
2017
1119
5921
1747
1694
Z30.
1444
30.
0015
5.12
249
0.06
560.
2573
10.
0033
0.04
588
0.00
0422
8118
1840
1114
7617
907
865
Z40.
1266
10.
0013
6.10
193
0.06
790.
3496
10.
0039
0.09
052
0.00
0820
5118
1991
1019
3318
1752
1594
Z50.
1285
60.
0013
6.01
834
0.07
330.
3395
90.
0042
0.09
138
0.00
0820
7818
1979
1118
8520
1767
1591
Z60.
1659
40.
0017
10.4
3208
0.12
130.
4560
00.
0054
0.11
158
0.00
0925
1717
2474
1124
2224
2138
1796
Z70.
1243
00.
0013
4.92
813
0.05
860.
2875
80.
0034
0.08
534
0.00
0720
1918
1807
1016
2917
1655
1381
Z80.
1391
50.
0014
5.15
288
0.06
150.
2686
50.
0033
0.06
272
0.00
0522
1717
1845
1015
3417
1230
1069
Z90.
1215
60.
0014
5.22
691
0.07
470.
3119
50.
0044
0.09
157
0.00
1319
7920
1857
1217
5021
1771
2388
Z10
0.17
091
0.00
182.
7991
50.
0359
0.11
881
0.00
160.
0378
60.
0004
2567
1713
5510
724
975
17
28Z1
10.
1307
70.
0013
5.71
678
0.06
590.
3170
90.
0037
0.12
493
0.00
1221
0818
1934
1017
7618
2379
2284
Z12
0.12
315
0.00
135.
7465
50.
0669
0.33
849
0.00
400.
0912
50.
0008
2002
1819
3810
1879
1917
6515
94Z1
30.
1247
50.
0013
5.87
342
0.06
900.
3415
30.
0041
0.09
019
0.00
0820
2518
1957
1018
9419
1745
1594
Z14
0.14
798
0.00
153.
6881
20.
0452
0.18
080
0.00
220.
0874
90.
0008
2323
1715
6910
1071
1216
9515
46Z1
50.
1607
00.
0016
9.74
268
0.11
480.
4397
70.
0052
0.11
490
0.00
1024
6317
2411
1123
5023
2198
1895
Z16
0.13
315
0.00
135.
8138
40.
0724
0.31
672
0.00
400.
0901
10.
0009
2140
1819
4911
1774
2017
4417
83Z1
70.
1466
10.
0015
5.83
191
0.07
070.
2885
50.
0035
0.10
258
0.00
1023
0717
1951
1116
3418
1974
1871
Z18
0.12
789
0.00
135.
9118
00.
0649
0.33
542
0.00
360.
1040
60.
0012
2069
1819
6310
1865
1720
0121
90Z1
90.
1248
50.
0013
5.56
734
0.06
850.
3234
70.
0040
0.07
900
0.00
0820
2718
1911
1118
0719
1537
1589
Z20
0.15
886
0.00
168.
8268
80.
0999
0.40
307
0.00
460.
1070
60.
0009
2444
1723
2010
2183
2120
5617
89Z2
10.
1892
00.
0019
6.10
539
0.07
770.
2341
10.
0030
0.04
056
0.00
0427
3517
1991
1113
5616
804
750
Z22
0.12
391
0.00
135.
7611
10.
0669
0.33
720.
0039
0.09
997
0.00
0920
1318
1941
1018
7319
1926
1793
Z23
0.12
507
0.00
134.
9955
00.
0613
0.28
969
0.00
350.
0919
60.
0009
2030
1818
1910
1640
1817
7816
81Z2
40.
1241
50.
0013
6.01
000
0.06
570.
3511
20.
0038
0.10
099
0.00
0920
1718
1977
1019
4018
1945
1696
Z25
0.13
020
0.00
134.
3085
80.
0520
0.23
999
0.00
290.
0636
50.
0006
2101
1816
9510
1387
1512
4711
66Z2
60.
1363
70.
0014
8.46
477
0.10
400.
4501
70.
0055
0.08
511
0.00
1021
8218
2282
1123
9624
1651
1911
0Z2
70.
1602
70.
0017
9.49
773
0.10
710.
4298
20.
0048
0.12
856
0.00
1224
5917
2387
1023
0522
2444
2194
Z28
0.16
938
0.00
181.
7846
30.
0221
0.07
640
0.00
090.
1450
10.
0018
2552
1810
408
475
627
3731
19Z2
90.
1185
90.
0013
5.10
378
0.06
600.
3122
70.
0040
0.09
807
0.00
1119
3519
1837
1117
5219
1891
2091
Z30
0.12
582
0.00
134.
8831
80.
0561
0.28
161
0.00
320.
0782
40.
0008
2040
1917
9910
1600
1615
2315
78Z3
10.
1358
30.
0014
7.13
847
0.08
560.
3812
10.
0046
0.10
893
0.00
1121
7518
2129
1120
8221
2090
1996
Z32
0.13
183
0.00
145.
9685
40.
0705
0.32
835
0.00
390.
0979
70.
0010
2123
1819
7110
1830
1918
8918
86Z3
30.
1161
60.
0012
4.86
409
0.05
640.
3036
60.
0035
0.07
986
0.00
0818
9819
1796
1017
0917
1553
1590
Z34
0.11
510
0.00
125.
2784
30.
064
0.33
264
0.00
410.
0976
90.
0010
1881
1818
6510
1851
2018
8417
98Z3
50.
1218
50.
0012
5.53
465
0.06
280.
3294
30.
0038
0.09
922
0.00
0919
8318
1906
1018
3618
1912
1793
Z36
0.16
486
0.00
1710
.294
940.
1203
0.45
293
0.00
540.
1291
30.
0012
2506
1724
6211
2408
2424
5521
96Z3
70.
1411
40.
0014
5.08
130
0.05
780.
2611
30.
0030
0.10
147
0.00
0922
4117
1833
1014
9615
1953
1667
-31-
Chapter 2 Supplementary Material
Rat
ios
App
aren
t age
s (M
a)Sp
ot20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
Con
Cor
ny P
oint
Par
agne
iss C
P5 (c
ontin
ued)
Z38
0.12
807
0.00
145.
5872
30.
0731
0.31
651
0.00
400.
0859
60.
0011
2072
1919
1411
1773
2016
6720
86Z3
90.
1224
10.
0013
5.82
410
0.07
280.
3451
40.
0043
0.09
948
0.00
1119
9218
1950
1119
1121
1917
1996
Z40
0.15
837
0.00
161.
1355
80.
0143
0.05
202
0.00
070.
2137
20.
0023
2438
1777
07
327
439
1539
13Z4
10.
1161
70.
0012
5.28
070
0.06
390.
3296
80.
004
0.09
512
0.00
1118
9818
1866
1018
3719
1837
2097
Z42
0.12
650
0.00
135.
7377
40.
0634
0.32
901
0.00
360.
1084
30.
0016
2050
1819
3710
1834
1820
8130
89Z4
30.
1245
30.
0013
5.74
504
0.07
020.
3346
30.
0041
0.10
805
0.00
1220
2218
1938
1118
6120
2074
2292
Z44
0.12
700
0.00
134.
9140
90.
0667
0.28
071
0.00
380.
1016
40.
0019
2057
1818
0511
1595
1919
5736
78Z4
50.
1325
40.
0027
5.97
230
0.12
320.
3268
50.
0051
0.09
759
0.00
2021
3235
1972
1818
2325
1882
3786
Z46
0.12
647
0.00
146.
3392
80.
0809
0.36
363
0.00
450.
1065
0.00
1420
5019
2024
1119
9921
2045
2598
Z47
0.12
528
0.00
135.
8334
20.
0723
0.33
777
0.00
410.
0920
70.
0009
2033
1919
5111
1876
2017
8017
92Z4
80.
1207
80.
0012
5.64
334
0.06
640.
3389
50.
004
0.09
999
0.00
0919
6818
1923
1018
8219
1926
1796
Z49
0.11
670
0.00
135.
5421
60.
0648
0.34
466
0.00
380.
1019
20.
0010
1906
2019
0710
1909
1819
6219
100
Z50
0.13
072
0.00
164.
8162
00.
0628
0.26
724
0.00
320.
0659
10.
0010
2108
2117
8811
1527
1612
9019
72Z5
10.
1224
70.
0014
5.75
410
0.06
650.
3408
70.
0037
0.10
633
0.00
1319
9320
1940
1018
9118
2043
2495
Z52
0.12
359
0.00
135.
5538
20.
0672
0.32
598
0.00
390.
1027
50.
0010
2009
1919
0910
1819
1919
7719
91Z5
30.
1319
50.
0016
6.44
136
0.08
580.
3541
00.
0044
0.11
454
0.00
1421
2421
2038
1219
5421
2192
2692
Z54
0.14
804
0.00
164.
7450
50.
0583
0.23
255
0.00
280.
0410
20.
0004
2323
1817
7510
1348
1581
38
58Z5
50.
1263
20.
0014
6.01
512
0.07
690.
3454
60.
0043
0.10
103
0.00
1420
4719
1978
1119
1321
1945
2593
Z56
0.12
100
0.00
125.
7570
50.
0664
0.34
520
0.00
390.
0945
10.
0011
1971
1819
4010
1912
1918
2519
97Z5
70.
1597
20.
0017
8.96
776
0.11
290.
4072
30.
0051
0.11
801
0.00
1524
5318
2335
1222
0223
2255
2790
Z58
0.14
047
0.00
156.
3100
40.
0813
0.32
582
0.00
410.
1001
0.00
1422
3319
2020
1118
1820
1928
2681
Z60
0.11
515
0.00
135.
3516
20.
0685
0.33
713
0.00
410.
1000
20.
0015
1882
2018
7711
1873
2019
2728
100
Z61
0.12
216
0.00
135.
8578
80.
0678
0.34
831
0.00
390.
1064
40.
0019
1988
1919
5510
1927
1920
4435
97Z6
30.
1245
40.
0014
5.64
860
0.07
130.
3290
30.
0041
0.09
733
0.00
1520
2219
1924
1118
3420
1877
2891
Z64
0.11
938
0.00
145.
0773
20.
0622
0.30
860
0.00
360.
0964
0.00
1019
4720
1832
1017
3418
1860
1889
Z65
0.15
888
0.00
169.
8669
10.
1128
0.45
042
0.00
520.
1214
80.
0010
2444
1724
2211
2397
2323
1718
98Z6
60.
1272
50.
0013
5.76
532
0.06
750.
3286
10.
0038
0.10
466
0.00
0920
6018
1941
1018
3218
2012
1789
Z67
0.12
924
0.00
154.
8644
30.
0619
0.27
304
0.00
330.
0756
70.
0009
2088
2017
9611
1556
1714
7417
75Z6
80.
1230
00.
0013
4.94
914
0.05
850.
2918
40.
0035
0.08
711
0.00
0820
0018
1811
1016
5117
1688
1483
Z69
0.15
736
0.00
207.
1478
40.
1023
0.32
946
0.00
440.
1272
20.
0020
2428
2121
3013
1836
2124
2136
76Z7
00.
1573
60.
0016
9.00
953
0.10
430.
4152
40.
0048
0.12
565
0.00
1124
2817
2339
1122
3922
2392
2092
Z72
0.12
743
0.00
135.
5074
00.
0628
0.31
347
0.00
360.
0951
60.
0008
2063
1819
0210
1758
1818
3715
85Z7
30.
1610
40.
0016
7.73
504
0.09
430.
3483
70.
0043
0.08
372
0.00
0724
6717
2201
1119
2720
1625
1478
Z74
0.16
086
0.00
178.
6254
30.
1017
0.38
889
0.00
460.
0926
20.
0008
2465
1722
9911
2118
2117
9015
86Z7
50.
1243
50.
0013
5.40
590
0.06
500.
3154
40.
0038
0.07
850.
0008
2020
1818
8610
1767
1915
2815
88Z7
60.
1205
80.
0013
4.89
043
0.05
820.
2942
70.
0035
0.08
815
0.00
0819
6518
1801
1016
6317
1708
1585
Z77
0.13
544
0.00
146.
6780
70.
0816
0.35
773
0.00
440.
1027
40.
0010
2170
1820
7011
1971
2119
7718
91Z7
80.
1243
90.
0013
6.13
860
0.07
190.
3580
00.
0042
0.10
771
0.00
1020
2018
1996
1019
7320
2068
1898
Z79
0.15
785
0.00
168.
0530
10.
1033
0.37
004
0.00
480.
0878
90.
0011
2433
1822
3712
2030
2217
0320
83Z8
20.
1265
80.
0013
6.31
388
0.07
350.
3618
20.
0042
0.10
488
0.00
0920
5118
2020
1019
9120
2016
1797
-32-
Chapter 2 Supplementary MaterialR
atio
sA
ppar
ent a
ges (
Ma)
Spot
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
% C
on
Cor
ny P
oint
Par
agne
iss C
P5 (c
ontin
ued)
Z83
0.12
288
0.00
135.
5370
40.
0723
0.32
682
0.00
420.
0893
90.
0011
1999
1919
0611
1823
2117
3120
91Z8
40.
1180
70.
0012
5.66
684
0.07
090.
3481
90.
0044
0.09
059
0.00
0919
2718
1926
1119
2621
1753
1710
0
Cor
n y P
oint
Par
agne
iss C
P18
Z10.
1600
20.
0016
8.24
260
0.08
120.
3736
30.
0037
0.10
969
0.00
0824
5617
2258
920
4717
2104
1583
Z20.
1626
20.
0017
9.93
530
0.11
510.
4431
40.
0052
0.12
305
0.00
1124
8317
2429
1123
6523
2346
1995
Z30.
1238
30.
0015
5.50
350
0.06
290.
3223
40.
0033
0.15
363
0.00
2820
1221
1901
1018
0116
2889
4990
Z40.
1585
60.
0016
9.41
630
0.11
700.
4307
90.
0054
0.12
641
0.00
1324
4017
2379
1123
0924
2406
2395
Z50.
1932
60.
0021
11.5
5450
0.14
020.
4338
00.
0052
0.13
140
0.00
1327
7017
2569
1123
2323
2495
2384
Z80.
1226
20.
0013
5.68
290
0.06
430.
3361
60.
0038
0.10
417
0.00
0919
9518
1929
1018
6818
2003
1694
Z90.
1220
90.
0012
5.55
730
0.06
530.
3301
50.
0039
0.07
458
0.00
0619
8718
1910
1018
3919
1454
1293
Z10
0.16
779
0.00
199.
6610
00.
1117
0.41
765
0.00
460.
1025
50.
0012
2536
1924
0311
2250
2119
7322
89Z1
10.
1628
70.
0017
10.2
7120
0.11
590.
4574
30.
0051
0.11
863
0.00
1124
8618
2460
1024
2823
2266
2098
Z12
0.12
423
0.00
136.
1061
00.
0688
0.35
682
0.00
40.
1131
70.
0020
2018
1819
9110
1967
1921
6736
97Z1
30.
1279
70.
0014
5.95
540
0.07
770.
3375
40.
0043
0.10
877
0.00
1520
7020
1969
1118
7521
2087
2691
Z14
0.19
317
0.00
1914
.213
600.
1589
0.53
370
0.00
600.
1427
30.
0012
2769
1627
6411
2757
2526
9721
100
Z15
0.12
411
0.00
126.
0257
00.
0661
0.35
218
0.00
390.
1360
80.
0012
2016
1819
8010
1945
1925
7922
96Z1
60.
1190
70.
0012
4.90
430
0.05
440.
2987
50.
0033
0.10
531
0.00
1019
4218
1803
916
8516
2024
1787
Z17
0.12
444
0.00
126.
0928
00.
0682
0.35
510
0.00
400.
1095
20.
0009
2021
1819
8910
1959
1921
0116
97Z1
80.
1559
90.
0016
9.57
630
0.11
130.
4453
00.
0052
0.12
093
0.00
1024
1317
2395
1123
7423
2308
1898
Z19
0.12
231
0.00
126.
0290
00.
0710
0.35
758
0.00
430.
1137
10.
0011
1990
1819
8010
1971
2021
7720
99Z2
10.
1214
90.
0012
6.13
370
0.07
450.
3663
20.
0045
0.10
536
0.00
1219
7818
1995
1120
1221
2025
2210
2Z2
20.
1691
00.
0022
8.79
260
0.10
810.
3774
50.
0041
0.12
598
0.00
9025
4921
2317
1120
6419
2398
161
81Z2
30.
1196
40.
0012
5.86
550
0.06
940.
3556
40.
0042
0.10
369
0.00
1119
5118
1956
1019
6220
1994
2010
1Z2
40.
1193
00.
0012
5.57
680
0.06
340.
3390
90.
0039
0.10
082
0.00
1219
4618
1913
1018
8219
1942
2197
Z25
0.16
538
0.00
1710
.335
300.
1312
0.45
334
0.00
580.
1271
90.
0021
2511
1724
6512
2410
2624
2037
96Z2
60.
1675
20.
0018
10.6
8420
0.11
760.
4626
60.
0050
0.22
957
0.00
6125
3318
2496
1024
5122
4177
100
97Z2
70.
1276
30.
0014
5.50
990
0.06
630.
3134
70.
0036
0.10
519
0.00
5420
6620
1902
1017
5818
2022
9985
Z28
0.15
510
0.00
169.
3846
00.
1147
0.43
889
0.00
540.
1369
30.
0015
2403
1723
7611
2346
2425
9426
98Z2
90.
1216
30.
0012
6.08
120
0.07
080.
3626
70.
0042
0.11
344
0.00
1619
8018
1988
1019
9520
2172
2910
1Z3
00.
1451
70.
0015
6.98
730
0.07
520.
3491
30.
0038
0.11
371
0.00
1622
9017
2110
1019
3018
2177
2984
Z31
0.14
296
0.00
176.
9797
00.
0882
0.35
413
0.00
420.
1270
20.
0017
2263
2021
0911
1954
2024
1730
86Z3
30.
1270
30.
0013
5.75
560
0.06
960.
3283
20.
0039
0.10
351
0.00
1320
5719
1940
1018
3019
1991
2389
Z34
0.15
715
0.00
168.
8710
00.
1065
0.40
944
0.00
490.
1471
40.
0017
2425
1823
2511
2212
2227
7529
91Z3
50.
1317
10.
0014
6.30
850
0.07
200.
3473
60.
0039
0.13
117
0.00
1521
2118
2020
1019
2219
2491
2691
Z36
0.11
913
0.00
133.
9829
00.
0446
0.24
263
0.00
260.
0829
10.
0011
1943
1916
319
1400
1316
1020
72Z3
80.
1379
30.
0015
7.43
120
0.08
560.
3909
20.
0043
0.14
832
0.00
1722
0119
2165
1021
2720
2795
3197
Z39
0.16
453
0.00
1710
.191
200.
1224
0.44
874
0.00
530.
0859
40.
0010
2503
1724
5211
2390
2416
6619
95Z4
00.
1650
40.
0017
10.3
5170
0.11
850.
4548
40.
0051
0.13
729
0.00
1525
0817
2467
1124
1723
2600
2796
Z41
0.16
485
0.00
1810
.148
700.
1288
0.44
637
0.00
560.
1255
60.
0016
2506
1824
4812
2379
2523
9129
95Z4
20.
1810
80.
0022
12.8
0610
0.18
060.
5127
00.
0068
0.06
632
0.00
1026
6320
2666
1326
6829
1298
1810
0Z4
30.
1276
50.
0013
6.33
210
0.07
560.
3598
90.
0043
0.10
987
0.00
1220
6618
2023
1019
8220
2107
2396
Z44
0.12
525
0.00
134.
7934
00.
0564
0.27
764
0.00
330.
0454
00.
0005
2032
1817
8410
1580
1789
810
78
-33-
Chapter 2 Supplementary Material
Rat
ios
App
aren
t age
s (M
a)Sp
ot20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
Con
Cor
ny P
oint
Par
agne
iss C
P18
(con
tinue
d)Z4
50.
1294
70.
0014
6.36
130
0.07
880.
3564
60.
0043
0.11
370
0.00
1520
9119
2027
1119
6520
2177
2794
Z46
0.16
985
0.00
189.
9744
00.
1250
0.42
606
0.00
530.
1477
00.
0018
2556
1724
3212
2288
2427
8431
90Z4
80.
1228
20.
0013
5.91
600
0.07
090.
3494
90.
0042
0.10
636
0.00
1319
9818
1964
1019
3220
2043
2397
Z49
0.16
933
0.00
198.
2880
00.
1057
0.35
532
0.00
440.
1073
70.
0017
2551
1922
6312
1960
2120
6231
77Z5
00.
1265
20.
0013
6.00
970
0.08
160.
3445
20.
0046
0.10
262
0.00
1520
5018
1977
1219
0822
1975
2793
Z51
0.14
509
0.00
185.
8519
00.
0765
0.29
249
0.00
350.
1247
20.
0031
2289
2119
5411
1654
1723
7656
72Z5
20.
1586
70.
0018
9.35
030
0.11
630.
4274
40.
0051
0.12
706
0.00
2524
4219
2373
1122
9423
2418
4594
Z53
0.17
391
0.00
2010
.816
600.
1406
0.45
113
0.00
560.
1350
70.
0026
2596
1925
0812
2400
2525
6145
92Z5
40.
1508
60.
0017
8.04
950
0.11
310.
3869
80.
0052
0.13
111
0.00
2723
5619
2237
1321
0924
2490
4990
Z55
0.12
247
0.00
135.
3502
00.
0693
0.31
687
0.00
400.
1156
40.
0021
1993
1918
7711
1774
2022
1238
89Z5
60.
1454
00.
0016
5.35
230
0.07
050.
2670
60.
0034
0.04
874
0.00
2022
9319
1877
1115
2617
962
3967
Z57
0.12
198
0.00
145.
8828
00.
0737
0.34
980
0.00
420.
0955
00.
0013
1985
2019
5911
1934
2018
4425
97Z5
80.
1757
90.
0020
9.29
290
0.12
0.38
327
0.00
470.
0848
00.
0037
2614
1923
6712
2092
2216
4569
80Z6
00.
1647
60.
0017
10.3
3900
0.13
140.
4551
30.
0058
0.12
971
0.00
2025
0517
2466
1224
1826
2465
3697
Cor
ny P
oint
Par
agne
iss C
P10
Z10.
1500
00.
0015
7.72
970
0.08
670.
3737
50.
0042
0.11
892
0.00
1123
4617
2200
1020
4720
2271
1987
Z20.
1476
60.
0016
8.34
430
0.10
330.
4098
80.
0050
0.12
797
0.00
1523
1918
2269
1122
1423
2434
2695
Z30.
1771
10.
0019
10.8
3399
0.13
260.
4438
70.
0054
0.13
173
0.00
1326
2617
2509
1123
6824
2501
2290
Z40.
1803
40.
0019
11.8
4173
0.14
330.
4765
40.
0057
0.14
468
0.00
1626
5617
2592
1125
1225
2731
2895
Z50.
1154
80.
0013
5.01
360
0.06
330.
3151
30.
0039
0.09
957
0.00
1218
8720
1822
1117
6619
1919
2394
Z60.
1641
80.
0017
9.67
044
0.11
720.
4273
00.
0052
0.12
066
0.00
1124
9917
2404
1122
9423
2303
2092
Z70.
1132
40.
0011
4.57
929
0.05
520.
2933
90.
0036
0.07
845
0.00
0718
5218
1746
1016
5918
1527
1390
Z80.
1147
80.
0012
5.05
653
0.05
870.
3195
50.
0037
0.08
650
0.00
0718
7718
1829
1017
8818
1677
1495
Z90.
1228
10.
0013
5.77
895
0.06
840.
3412
80.
0040
0.09
932
0.00
1019
9718
1943
1018
9319
1914
1895
Z10
0.12
185
0.00
145.
9485
30.
0752
0.35
398
0.00
420.
1047
20.
0014
1984
2019
6811
1954
2020
1325
98Z1
10.
1613
00.
0017
9.97
938
0.12
210.
4487
30.
0054
0.13
285
0.00
1424
6918
2433
1123
9024
2521
2597
Z12
0.11
622
0.00
135.
4780
60.
0718
0.34
186
0.00
430.
0989
00.
0011
1899
2018
9711
1896
2119
0620
100
Z13
0.13
815
0.00
164.
4541
60.
0569
0.23
381
0.00
280.
0630
80.
0010
2204
2017
2311
1354
1512
3619
61Z1
40.
1224
10.
0013
5.82
345
0.06
990.
3450
50.
0041
0.11
253
0.00
1219
9218
1950
1019
1120
2155
2196
Z15
0.11
438
0.00
125.
2584
80.
0650
0.33
341
0.00
410.
0976
60.
0012
1870
1918
6211
1855
2018
8322
99Z1
60.
1355
90.
0014
7.43
771
0.09
980.
3979
40.
0053
0.11
999
0.00
1421
7218
2166
1221
6024
2291
2699
Z17
0.15
807
0.00
169.
5096
60.
1152
0.43
635
0.00
540.
1272
10.
0012
2435
1723
8911
2334
2424
2022
96Z1
80.
1431
30.
0015
7.04
646
0.08
350.
3570
20.
0043
0.10
076
0.00
2722
6518
2117
1119
6820
1941
4987
Z19
0.12
210
0.00
125.
9938
90.
0711
0.35
605
0.00
430.
1105
30.
0011
1987
1819
7510
1963
2021
1919
99Z2
00.
1151
90.
0013
4.50
759
0.06
370.
2838
70.
0039
0.04
705
0.00
1518
8320
1732
1216
1120
929
2986
Z21
0.17
044
0.00
199.
9460
00.
1382
0.42
328
0.00
570.
1386
80.
0020
2562
1924
3013
2275
2626
2535
89Z2
20.
1502
80.
0016
8.72
634
0.12
020.
4211
70.
0056
0.12
380
0.00
1823
4919
2310
1322
6626
2359
3296
Z24
0.16
276
0.00
197.
4165
90.
1029
0.33
047
0.00
440.
0991
00.
0036
2485
1921
6312
1841
2119
1067
74Z2
50.
1394
00.
0016
6.30
980
0.08
900.
3283
40.
0044
0.11
079
0.00
2822
2020
2020
1218
3021
2124
5282
Z26
0.11
972
0.00
144.
3113
30.
0604
0.26
125
0.00
350.
0938
20.
0025
1952
2116
9612
1496
1818
1347
77Z2
70.
1270
20.
0015
6.11
476
0.09
070.
3491
90.
0049
0.10
760
0.00
2820
5721
1992
1319
3123
2066
5194
-34-
Chapter 2 Supplementary MaterialR
atio
sA
ppar
ent a
ges (
Ma)
Spot
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
% C
on
Cor
ny P
oint
Par
agne
iss C
P10
(con
tinue
d)Z2
30.
1285
10.
0015
5.26
733
0.07
480.
2973
50.
0040
0.10
412
0.00
2520
7821
1864
1216
7820
2002
4681
Z28
0.12
073
0.00
125.
6849
00.
0748
0.34
155
0.00
450.
1261
50.
0021
1967
1819
2911
1894
2224
0138
96Z2
90.
1214
80.
0014
6.13
412
0.09
190.
3662
70.
0054
0.10
401
0.00
2319
7820
1995
1320
1225
2000
4110
2Z3
00.
1227
90.
0013
5.97
589
0.07
840.
3530
10.
0045
0.10
275
0.00
1319
9719
1972
1119
4922
1977
2398
Z31
0.12
232
0.00
145.
6570
50.
0749
0.33
540
0.00
430.
0956
60.
0011
1990
2019
2511
1865
2118
4720
94Z3
20.
1223
10.
0013
5.74
047
0.07
690.
3404
30.
0045
0.09
263
0.00
1019
9019
1938
1218
8921
1791
1995
Z33
0.12
299
0.00
145.
9036
70.
0804
0.34
817
0.00
460.
0996
10.
0010
2000
1919
6212
1926
2219
1919
96Z3
40.
1154
10.
0012
5.42
192
0.06
740.
3407
30.
0043
0.10
355
0.00
0918
8618
1888
1118
9020
1992
1710
0Z3
50.
1197
00.
0013
5.77
573
0.07
620.
3499
70.
0046
0.10
989
0.00
1419
5219
1943
1119
3522
2107
2699
Z36
0.12
137
0.00
125.
8755
40.
0750
0.35
114
0.00
450.
1048
70.
0010
1976
1819
5811
1940
2120
1618
98Z3
70.
1277
70.
0014
6.28
678
0.08
690.
3568
10.
0048
0.11
166
0.00
1320
6819
2017
1219
6723
2140
2495
Z38
0.11
647
0.00
125.
3014
40.
0656
0.33
015
0.00
410.
1084
30.
0010
1903
1818
6911
1839
2020
8118
97Z3
90.
1178
90.
0012
5.97
930
0.07
300.
3678
60.
0046
0.11
408
0.00
1219
2518
1973
1120
1921
2184
2110
5Z4
00.
1652
30.
0018
7.58
544
0.09
910.
3330
40.
0043
0.10
295
0.00
1225
1018
2183
1218
5321
1981
2274
Z41
0.11
906
0.00
135.
5150
00.
0749
0.33
593
0.00
450.
1016
30.
0011
1942
1919
0312
1867
2219
5621
96Z4
20.
1172
30.
0013
5.61
527
0.07
370.
3475
20.
0044
0.10
445
0.00
1419
1520
1918
1119
2321
2008
2610
0Z4
30.
1592
20.
0016
9.79
476
0.11
610.
4462
40.
0054
0.13
268
0.00
1324
4717
2416
1123
7924
2518
2297
Z44
0.12
153
0.00
125.
9938
20.
0729
0.35
778
0.00
440.
1072
20.
0010
1979
1819
7511
1972
2120
5918
100
Z45
0.11
583
0.00
125.
4703
90.
0712
0.34
256
0.00
450.
0746
70.
0008
1893
1818
9611
1899
2214
5615
100
Z46
0.11
683
0.00
125.
0631
30.
0656
0.31
442
0.00
400.
1249
10.
0021
1908
1918
3011
1762
2023
7937
92Z4
70.
1164
70.
0012
5.40
520
0.06
990.
3366
30.
0044
0.09
784
0.00
1119
0318
1886
1118
7121
1887
2198
Z48
0.13
425
0.00
174.
7835
00.
0665
0.25
850.
0034
0.06
731
0.00
1421
5421
1782
1214
8217
1317
2669
Z49
0.16
206
0.00
177.
8216
70.
1134
0.35
015
0.00
510.
0792
60.
0011
2477
1822
1113
1935
2415
4220
78Z5
00.
1205
80.
0012
5.91
376
0.07
660.
3557
20.
0047
0.10
109
0.00
1019
6518
1963
1119
6222
1947
1810
0
Cou
lta G
rano
dior
iteZ1
0.17
101
0.00
207.
6633
20.
1016
0.32
517
0.00
410.
1264
10.
0021
2568
2021
9212
1815
2024
0637
71Z2
0.16
829
0.00
179.
6969
00.
1381
0.41
791
0.00
60.
0594
30.
0008
2541
1724
0613
2251
2711
6716
89Z3
0.17
021
0.00
195.
9556
40.
0873
0.25
379
0.00
370.
1137
30.
0018
2560
1819
6913
1458
1921
7733
57Z4
0.17
472
0.00
1810
.557
230.
1309
0.43
835
0.00
540.
1616
30.
0019
2603
1724
8512
2343
2430
2833
90Z5
0.16
746
0.00
1710
.957
790.
1551
0.47
461
0.00
680.
1435
40.
0020
2533
1725
2013
2504
3027
1135
99Z7
0.16
756
0.00
1710
.625
410.
1397
0.45
995
0.00
610.
1387
10.
0017
2533
1724
9112
2439
2726
2629
96Z8
0.16
635
0.00
1710
.778
940.
1417
0.46
997
0.00
620.
1328
90.
0016
2521
1725
0412
2483
2725
2229
98Z9
0.19
233
0.00
196.
5384
20.
0830
0.24
658
0.00
320.
0325
70.
0004
2762
1620
5111
1421
1664
87
51Z1
00.
1669
30.
0018
8.24
557
0.12
580.
3583
50.
0055
0.12
135
0.00
1825
2718
2258
1419
7426
2315
3278
Z11
0.16
746
0.00
1710
.992
460.
1365
0.47
611
0.00
590.
1399
20.
0019
2532
1725
2312
2510
2626
4733
99Z1
20.
1813
10.
0019
12.3
6338
0.16
400.
4946
20.
0066
0.14
264
0.00
1726
6517
2632
1225
9128
2695
3197
Z13
0.16
651
0.00
1810
.410
420.
1631
0.45
352
0.00
720.
1493
10.
0024
2523
1824
7215
2411
3228
1343
96Z1
50.
1854
60.
0019
12.7
7366
0.17
830.
4995
80.
0071
0.14
566
0.00
2027
0217
2663
1326
1230
2749
3597
Z16
0.16
599
0.00
1710
.520
950.
1387
0.45
972
0.00
620.
1358
80.
0017
2518
1724
8212
2438
2725
7530
97Z1
70.
1706
20.
0017
9.83
905
0.14
510.
4182
90.
0063
0.14
783
0.00
2225
6417
2420
1422
5328
2787
3888
Z18
0.16
938
0.00
1710
.103
020.
1353
0.43
262
0.00
590.
0883
70.
0011
2552
1724
4412
2318
2617
1221
91
-35-
Chapter 2 Supplementary Material
Rat
ios
App
aren
t age
s (M
a)Sp
ot20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th20
7 Pb/20
6 Pb20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
Con
Cou
lta G
rano
dior
ite (c
ontin
ued)
Z14
0.16
654
0.00
1710
.645
600.
1404
0.46
365
0.00
620.
1370
60.
0017
2523
1724
9312
2456
2725
9630
97Z1
90.
1661
20.
0017
10.6
3060
0.15
20.
4641
90.
0067
0.13
810
0.00
1925
1917
2491
1324
5830
2615
3498
Z20
0.16
609
0.00
1710
.096
910.
1419
0.44
091
0.00
630.
1329
40.
0018
2519
1724
4413
2355
2825
2332
93
Milt
alie
Ort
hogn
eiss
Z20.
1232
90.
0013
6.23
586
0.08
160.
3668
40.
0048
0.10
721
0.00
1120
0418
2010
1120
1523
2059
2110
1Z3
0.12
534
0.00
156.
2571
10.
0829
0.36
204
0.00
440.
1117
90.
0015
2034
2120
1312
1992
2121
4228
98Z4
0.12
410
0.00
136.
2606
00.
0846
0.36
590
0.00
490.
1063
0.00
1220
1618
2013
1220
1023
2042
2110
0Z5
0.12
328
0.00
136.
3309
80.
0829
0.37
249
0.00
480.
1046
0.00
1220
0418
2023
1120
4123
2011
2110
2Z6
0.12
478
0.00
136.
3664
90.
0829
0.37
006
0.00
480.
1033
60.
0011
2026
1820
2811
2030
2219
8820
100
Z70.
1233
20.
0014
6.30
205
0.09
120.
3706
60.
0052
0.10
256
0.00
1320
0520
2019
1320
3324
1973
2410
1Z8
0.12
434
0.00
136.
1859
60.
0837
0.36
085
0.00
480.
1018
80.
0012
2019
1920
0312
1986
2319
6121
98Z1
10.
1278
40.
0014
6.23
592
0.08
240.
3538
20.
0046
0.11
386
0.00
1320
6818
2010
1219
5322
2180
2394
Z12
0.12
441
0.00
166.
4452
60.
1133
0.37
611
0.00
630.
0912
10.
0025
2020
2320
3915
2058
3017
6446
102
Z13
0.12
943
0.00
166.
1609
10.
0842
0.34
530
0.00
430.
1186
20.
0022
2090
2219
9912
1912
2022
6640
91Z1
40.
1250
90.
0014
6.09
107
0.07
740.
3532
20.
0044
0.10
848
0.00
1320
3019
1989
1119
5021
2082
2396
Z15
0.12
558
0.00
156.
1505
10.
0959
0.35
518
0.00
530.
1087
30.
0015
2037
2019
9714
1959
2520
8628
96Z1
60.
1236
60.
0014
6.22
387
0.08
600.
3650
60.
0048
0.10
457
0.00
1420
1020
2008
1220
0623
2010
2610
0Z1
70.
1243
20.
0013
6.28
162
0.08
690.
3664
80.
0051
0.09
738
0.00
1020
1918
2016
1220
1324
1878
1910
0Z1
80.
1245
90.
0014
6.37
622
0.08
480.
3712
00.
0048
0.10
272
0.00
1320
2319
2029
1220
3522
1976
2310
1Z1
90.
1232
80.
0013
6.10
200
0.07
910.
3590
40.
0046
0.10
231
0.00
1120
0418
1991
1119
7822
1969
2099
Milt
alie
Com
posit
eZ1
0.07
451
0.00
081.
7526
50.
0236
0.17
063
0.00
230.
0503
60.
0005
1055
2110
289
1016
1399
310
96Z2
0.07
943
0.00
142.
0571
90.
0382
0.18
787
0.00
270.
0571
80.
0010
1183
3311
3513
1110
1511
2419
94Z3
0.12
184
0.00
145.
6639
00.
0793
0.33
726
0.00
460.
0807
50.
0011
1983
2019
2612
1874
2215
7020
94Z4
0.12
342
0.00
145.
9965
30.
0852
0.35
246
0.00
490.
1011
0.00
1320
0619
1975
1219
4623
1947
2497
Z50.
0612
10.
0011
0.68
075
0.01
270.
0806
80.
0011
0.02
522
0.00
0464
737
527
850
07
503
877
Z60.
0758
30.
0010
1.67
329
0.02
610.
1600
80.
0022
0.04
989
0.00
0710
9127
998
1095
712
984
1488
Z70.
0790
80.
0010
2.02
102
0.02
980.
1854
00.
0025
0.05
607
0.00
0711
7425
1123
1010
9614
1103
1393
Z80.
1235
90.
0015
5.99
121
0.09
160.
3516
20.
0052
0.10
190.
0015
2009
2119
7513
1942
2519
6127
97Z9
0.07
915
0.00
092.
0629
50.
0298
0.18
907
0.00
260.
0586
90.
0007
1176
2311
3710
1116
1411
5313
95Z1
00.
0801
90.
0010
2.16
241
0.03
140.
1956
20.
0027
0.05
802
0.00
0712
0223
1169
1011
5214
1140
1396
Z11
0.12
493
0.00
136.
3029
70.
0901
0.36
591
0.00
520.
0971
90.
0012
2028
1820
1913
2010
2518
7522
99Z1
30.
1664
60.
0023
9.14
105
0.13
350.
3977
20.
0052
0.01
936
0.00
1325
2223
2352
1321
5924
388
2686
Z14
0.17
769
0.00
208.
4110
30.
1151
0.34
340
0.00
450.
2348
10.
0056
2631
1922
7612
1903
2242
6392
72Z1
50.
1230
10.
0013
5.78
231
0.07
970.
3409
30.
0046
0.10
595
0.00
1320
0019
1944
1218
9122
2035
2495
Z16
0.12
277
0.00
146.
0231
30.
0934
0.35
577
0.00
530.
1028
90.
0016
1997
2119
7914
1962
2519
8030
98Z1
70.
1246
40.
0013
5.99
452
0.08
110.
3488
40.
0047
0.10
224
0.00
1220
2419
1975
1219
2922
1968
2295
Z18
0.12
400
0.00
135.
9612
30.
0810
0.34
868
0.00
460.
1065
50.
0013
2015
1919
7012
1928
2220
4724
96
-36-
Chapter 2 Supplementary MaterialR
atio
sA
ppar
ent a
ges (
Ma)
Spot
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
% C
on
Milt
alie
Com
posit
e (c
ontin
ued)
Z19
0.07
498
0.00
111.
6856
00.
0275
0.16
304
0.00
220.
0493
40.
0007
1068
2910
0310
974
1297
314
91Z2
00.
1000
90.
0013
3.77
029
0.05
640.
2732
10.
0038
0.07
955
0.00
1016
2623
1586
1215
5719
1547
1996
Z21
0.12
469
0.00
135.
3116
40.
0719
0.30
899
0.00
410.
0945
40.
0012
2024
1918
7112
1736
2018
2622
86Z2
20.
1054
40.
0012
3.46
193
0.04
850.
2381
40.
0032
0.07
901
0.00
1017
2220
1519
1113
7717
1537
1880
Z23
0.08
460
0.00
102.
5401
20.
0377
0.21
775
0.00
310.
0638
80.
0009
1306
2212
8411
1270
1612
5216
97Z2
50.
1037
80.
0016
3.89
105
0.07
030.
2719
60.
0043
0.08
183
0.00
1716
9328
1612
1515
5122
1590
3292
Z26
0.16
231
0.00
168.
5052
60.
1152
0.38
007
0.00
520.
0153
60.
0002
2480
1722
8712
2077
2430
84
84Z2
70.
1256
00.
0015
3.31
738
0.05
100.
1915
40.
0029
0.03
609
0.00
0620
3720
1485
1211
3015
717
1255
Z28
0.17
657
0.00
1911
.912
00.
1699
0.48
930
0.00
690.
1367
60.
0019
2621
1825
9813
2568
3025
9134
98Z2
90.
0790
00.
0012
1.98
432
0.03
290.
1822
00.
0025
0.05
450.
0009
1172
2911
1011
1079
1410
7316
92Z3
00.
1242
30.
0014
4.96
190
0.07
710.
2897
00.
0045
0.02
838
0.00
0520
1819
1813
1316
4022
566
981
-37-
Chapter 2 Supplementary Material
Sup
plem
enta
ry T
able
B.
Hf
isot
opic
dat
a17
6 Lu
deca
y co
nsta
nts
Sod
erlu
nd e
t al
., 2
004
(1.8
67x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )
Anal
ysis
176 H
f/177 H
f2
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
206 P
b/20
7 Pb
age
(Ma)
Hf i
Hf
1SE
T DM
(Ga)
T DM
(cru
stal
)H
f iH
fT D
M(G
a)T D
M(c
rust
al)
Cou
lta
Gra
nodi
orite
CG
020.
2813
500.
0000
340.
0012
130.
0450
8025
410.
2812
914.
690.
602.
672.
760.
2812
914.
632.
672.
76CG
050.
2813
300.
0000
220.
0013
700.
0466
9525
330.
2812
643.
530.
392.
712.
820.
2812
643.
472.
712.
83CG
070.
2812
850.
0000
220.
0007
190.
0232
7325
330.
2812
503.
070.
392.
722.
850.
2812
503.
012.
732.
86CG
080.
2812
520.
0000
180.
0006
070.
0189
8125
210.
2812
231.
810.
312.
762.
930.
2812
231.
752.
762.
93CG
110.
2812
750.
0000
220.
0007
230.
0247
9425
320.
2812
402.
680.
392.
742.
880.
2812
402.
622.
742.
88CG
120.
2812
570.
0000
300.
0005
110.
0195
4326
650.
2812
315.
430.
532.
752.
800.
2812
315.
362.
752.
81CG
130.
2813
230.
0000
240.
0010
240.
0361
5425
230.
2812
743.
660.
422.
692.
810.
2812
743.
602.
702.
81CG
160.
2812
910.
0000
260.
0008
990.
0296
4325
180.
2812
482.
620.
462.
732.
870.
2812
482.
562.
732.
88CG
180.
2813
310.
0000
280.
0016
790.
0564
4825
520.
2812
493.
450.
492.
732.
840.
2812
493.
392.
732.
85CG
190.
2812
940.
0000
300.
0009
300.
0325
0525
190.
2812
492.
700.
532.
732.
870.
2812
492.
642.
732.
87CG
200.
2813
150.
0000
280.
0008
060.
0293
1625
190.
2812
763.
650.
492.
692.
810.
2812
763.
592.
692.
81CG
150.
2811
930.
0000
480.
0006
450.
0170
2927
020.
2811
603.
760.
842.
842.
940.
2811
603.
692.
842.
95M
iltal
ie G
neis
sM
O02
0.28
1437
0.00
0034
0.00
0691
0.02
3320
2004
0.28
1411
-3.3
90.
602.
522.
860.
2814
11-3
.44
2.52
2.86
MO
030.
2814
460.
0000
200.
0006
570.
0213
3920
340.
2814
21-2
.37
0.35
2.50
2.82
0.28
1421
-2.4
22.
502.
82M
O04
0.28
1392
0.00
0030
0.00
0563
0.01
8798
2016
0.28
1370
-4.5
50.
532.
572.
940.
2813
70-4
.60
2.57
2.95
MO
050.
2813
920.
0000
240.
0004
880.
0159
3320
040.
2813
73-4
.72
0.42
2.56
2.94
0.28
1373
-4.7
62.
572.
95M
O06
0.28
1425
0.00
0028
0.00
0578
0.02
0434
2026
0.28
1403
-3.1
80.
492.
522.
860.
2814
03-3
.23
2.53
2.87
MO
070.
2814
540.
0000
360.
0006
620.
0242
6120
050.
2814
29-2
.74
0.63
2.49
2.82
0.28
1429
-2.7
82.
492.
82M
O08
0.28
1442
0.00
0040
0.00
0528
0.01
9214
2019
0.28
1422
-2.6
50.
702.
502.
820.
2814
22-2
.70
2.50
2.83
MO
110.
2814
010.
0000
400.
0005
070.
0197
2820
680.
2813
81-2
.98
0.70
2.55
2.88
0.28
1381
-3.0
32.
552.
89M
O12
0.28
1453
0.00
0028
0.00
1017
0.03
6442
2020
0.28
1414
-2.9
10.
492.
512.
840.
2814
14-2
.96
2.52
2.84
MO
130.
2814
460.
0000
300.
0009
710.
0409
1320
900.
2814
07-1
.54
0.53
2.52
2.81
0.28
1407
-1.5
92.
522.
81M
O14
0.28
1419
0.00
0032
0.00
0597
0.01
8827
2030
0.28
1396
-3.3
30.
562.
532.
870.
2813
96-3
.37
2.54
2.88
MO
150.
2814
050.
0000
240.
0004
660.
0155
6420
370.
2813
87-3
.48
0.42
2.54
2.89
0.28
1387
-3.5
32.
552.
89M
O16
0.28
1451
0.00
0034
0.00
0679
0.02
5643
2010
0.28
1425
-2.7
60.
602.
502.
820.
2814
25-2
.81
2.50
2.83
MO
170.
2814
310.
0000
320.
0007
550.
0302
2720
190.
2814
02-3
.36
0.56
2.53
2.87
0.28
1402
-3.4
12.
532.
87M
O18
0.28
1391
0.00
0028
0.00
0515
0.01
9865
2023
0.28
1371
-4.3
70.
492.
572.
930.
2813
71-4
.41
2.57
2.94
MO
190.
2814
230.
0000
320.
0005
130.
0200
4920
040.
2814
03-3
.65
0.56
2.52
2.87
0.28
1403
-3.7
02.
532.
88M
S03
0.28
1472
0.00
0020
0.00
0525
0.02
2601
1983
0.28
1452
-2.4
00.
352.
462.
780.
2814
52-2
.44
2.46
2.78
MS04
0.28
1424
0.00
0022
0.00
0416
0.01
7892
2006
0.28
1408
-3.4
40.
392.
512.
860.
2814
08-3
.48
2.52
2.87
MS08
0.28
1409
0.00
0022
0.00
0579
0.02
5072
2009
0.28
1387
-4.1
40.
392.
552.
910.
2813
87-4
.18
2.55
2.91
MS11
0.28
1480
0.00
0022
0.00
1150
0.04
8968
2028
0.28
1436
-1.9
70.
392.
492.
790.
2814
36-2
.01
2.49
2.79
-38-
Chapter 2 Supplementary Material
176 L
u de
cay
cons
tant
sSod
erlu
nd e
t al
., 2
004
(1.8
67x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )
Anal
ysis
176 H
f/177 H
f2
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
206 P
b/20
7 Pb
age
(Ma)
Hf i
Hf
1SE
T DM
(Ga)
T DM
(cru
stal
)H
f iH
fT D
M(G
a)T D
M(c
rust
al)
MS15
0.28
1428
0.00
0013
0.00
0761
0.03
4263
2000
0.28
1399
-3.8
90.
232.
532.
890.
2813
99-3
.94
2.53
2.89
MS16
0.28
1439
0.00
0024
0.00
0595
0.02
5899
1997
0.28
1416
-3.3
60.
422.
512.
850.
2814
16-3
.40
2.51
2.86
MS17
0.28
1424
0.00
0024
0.00
0759
0.03
4062
2024
0.28
1395
-3.5
10.
422.
542.
880.
2813
95-3
.56
2.54
2.89
MS18
0.28
1411
0.00
0022
0.00
0530
0.02
2839
2015
0.28
1391
-3.8
70.
392.
542.
900.
2813
91-3
.92
2.54
2.90
Wild
man
Silt
ston
eD
3.1
0.28
1626
0.00
0042
0.00
0897
0.03
1717
2009
0.28
1592
3.15
0.74
2.27
2.45
0.28
1592
3.10
2.27
2.45
D2.
10.
2817
080.
0000
780.
0015
020.
0597
5220
180.
2816
505.
441.
372.
192.
310.
2816
505.
392.
202.
31D
6.1
0.28
1694
0.00
0088
0.00
1149
0.04
7413
2017
0.28
1650
5.40
1.54
2.19
2.31
0.28
1650
5.35
2.19
2.31
D4.
10.
2817
120.
0000
660.
0013
520.
0569
6420
240.
2816
605.
921.
162.
182.
280.
2816
605.
872.
182.
28D
39.1
0.28
1541
0.00
0028
0.00
1023
0.04
1325
2019
0.28
1502
0.18
0.49
2.39
2.64
0.28
1502
0.13
2.40
2.65
D5.
10.
2816
740.
0000
900.
0007
420.
0320
4320
220.
2816
455.
351.
582.
202.
310.
2816
455.
312.
202.
32D
7.1
0.28
1715
0.00
0080
0.00
1828
0.07
1108
2002
0.28
1645
4.89
1.40
2.20
2.33
0.28
1645
4.85
2.20
2.33
D41
.10.
2816
790.
0001
220.
0023
290.
0860
7720
360.
2815
893.
662.
142.
282.
430.
2815
893.
612.
292.
44D
8.1
0.28
1600
0.00
0078
0.00
0717
0.02
8800
2015
0.28
1573
2.60
1.37
2.30
2.49
0.28
1573
2.56
2.30
2.49
D40
.10.
2815
340.
0000
280.
0006
860.
0265
3820
140.
2815
080.
280.
492.
382.
630.
2815
080.
232.
392.
64D
9.1
0.28
1682
0.00
0056
0.00
0918
0.03
4033
2018
0.28
1647
5.31
0.98
2.20
2.31
0.28
1647
5.26
2.20
2.32
D11
.10.
2817
170.
0001
300.
0008
060.
0369
8920
240.
2816
866.
842.
282.
142.
220.
2816
866.
792.
142.
22D
15.1
0.28
1617
0.00
0050
0.00
0875
0.03
3658
2031
0.28
1583
3.35
0.88
2.28
2.45
0.28
1583
3.30
2.28
2.45
D12
.10.
2815
620.
0001
140.
0010
520.
0406
9820
130.
2815
220.
752.
002.
372.
600.
2815
220.
712.
372.
61Cor
ny P
oint
Par
agne
iss
CP5
-22
0.28
1612
0.00
0046
0.00
1272
0.05
2695
2013
0.28
1563
2.24
0.81
2.31
2.51
0.28
1563
2.19
2.31
2.51
CP5
-24
0.28
1451
0.00
0042
0.00
0679
0.02
7196
2017
0.28
1425
-2.6
00.
742.
502.
820.
2814
25-2
.65
2.50
2.82
CP5
-47
0.28
1615
0.00
0042
0.00
1175
0.04
9911
2033
0.28
1570
2.91
0.74
2.30
2.48
0.28
1570
2.86
2.30
2.48
CP5
-49
0.28
1586
0.00
0026
0.00
0544
0.02
0195
1906
0.28
1566
-0.1
00.
462.
302.
570.
2815
66-0
.15
2.31
2.58
CP5
-51
0.28
1645
0.00
0032
0.00
0782
0.02
8278
1993
0.28
1615
3.61
0.56
2.24
2.40
0.28
1615
3.57
2.24
2.41
CP5
-52
0.28
1573
0.00
0036
0.00
0695
0.02
7464
2009
0.28
1546
1.53
0.63
2.33
2.55
0.28
1546
1.49
2.33
2.55
CP5
-56
0.28
1655
0.00
0024
0.00
0530
0.02
0917
1971
0.28
1635
3.82
0.42
2.21
2.37
0.28
1635
3.77
2.21
2.38
CP5
-61
0.28
1690
0.00
0024
0.00
0985
0.03
8205
1988
0.28
1653
4.83
0.42
2.19
2.32
0.28
1653
4.79
2.19
2.33
CP5
-63
0.28
1667
0.00
0028
0.00
1029
0.04
2249
2022
0.28
1627
4.72
0.49
2.22
2.36
0.28
1627
4.67
2.22
2.36
CP5
-65
0.28
1359
0.00
0024
0.00
0673
0.02
3337
2444
0.28
1328
3.75
0.42
2.62
2.74
0.28
1328
3.69
2.62
2.75
CP5
-78
0.28
1595
0.00
0022
0.00
0578
0.02
2114
2020
0.28
1573
2.73
0.39
2.29
2.48
0.28
1573
2.68
2.30
2.49
CP5
-82
0.28
1712
0.00
0032
0.00
0837
0.03
0149
2051
0.28
1679
7.22
0.56
2.15
2.22
0.28
1679
7.17
2.15
2.22
CP5
-83
0.28
1651
0.00
0038
0.00
1164
0.04
6943
1999
0.28
1607
3.44
0.67
2.25
2.42
0.28
1607
3.39
2.25
2.42
CP1
8-02
0.28
1363
0.00
0038
0.00
0792
0.02
4970
2483
0.28
1325
4.58
0.67
2.62
2.72
0.28
1325
4.52
2.63
2.72
-39-
Chapter 2 Supplementary Material
176 L
u de
cay
cons
tant
sSod
erlu
nd e
t al
., 2
004
(1.8
67x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )
Anal
ysis
176 H
f/177 H
f2
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
206 P
b/20
7 Pb
age
(Ma)
Hf i
Hf
1SE
T DM
(Ga)
T DM
(cru
stal
)H
f iH
fT D
M(G
a)T D
M(c
rust
al)
CP1
8-12
0.28
1621
0.00
0017
0.00
0903
0.03
5883
2018
0.28
1586
3.16
0.30
2.28
2.45
0.28
1586
3.11
2.28
2.46
CP1
8-13
0.28
1639
0.00
0028
0.00
0985
0.03
3673
2070
0.28
1600
4.85
0.49
2.26
2.38
0.28
1600
4.80
2.26
2.39
CP1
8-14
0.28
1240
0.00
0024
0.00
0879
0.02
7112
2769
0.28
1193
6.51
0.42
2.80
2.82
0.28
1193
6.45
2.80
2.82
CP1
8-15
0.28
1602
0.00
0040
0.00
0903
0.03
5546
2016
0.28
1567
2.45
0.70
2.30
2.50
0.28
1567
2.40
2.31
2.50
CP1
8-19
0.28
1711
0.00
0040
0.00
1282
0.04
7537
1990
0.28
1662
5.23
0.70
2.18
2.30
0.28
1663
5.18
2.18
2.30
CP1
8-21
0.28
1681
0.00
0028
0.00
0994
0.03
8651
1978
0.28
1644
4.29
0.49
2.20
2.35
0.28
1644
4.24
2.20
2.35
CP1
8-23
0.28
1692
0.00
0044
0.00
0775
0.02
8583
1951
0.28
1663
4.36
0.77
2.17
2.32
0.28
1663
4.31
2.18
2.33
CP1
8-23
0.28
1574
0.00
0036
0.00
0052
0.00
2269
1951
0.28
1572
1.12
0.63
2.29
2.53
0.28
1572
1.07
2.29
2.53
CP1
8-24
0.28
1623
0.00
0028
0.00
0802
0.03
0436
1946
0.28
1593
1.76
0.49
2.27
2.49
0.28
1593
1.71
2.27
2.49
CP1
8-25
0.28
1059
0.00
0032
0.00
0543
0.01
9000
2511
0.28
1033
-5.1
70.
563.
013.
360.
2810
33-5
.23
3.02
3.37
CP1
8-28
0.28
1259
0.00
0034
0.00
0563
0.01
9565
2403
0.28
1233
-0.5
50.
602.
752.
990.
2812
33-0
.61
2.75
2.99
CP1
8-38
0.28
1585
0.00
0032
0.00
0479
0.01
9632
2201
0.28
1565
6.60
0.56
2.30
2.37
0.28
1565
6.55
2.30
2.38
CP1
8-43
0.28
1698
0.00
0034
0.00
0843
0.03
0728
2066
0.28
1665
7.05
0.60
2.17
2.24
0.28
1665
7.00
2.17
2.24
CP1
8-45
0.28
1668
0.00
0030
0.00
0913
0.03
6294
2091
0.28
1632
6.44
0.53
2.21
2.30
0.28
1632
6.39
2.22
2.30
CP1
8-48
0.28
1611
0.00
0032
0.00
0816
0.03
2290
1998
0.28
1580
2.47
0.56
2.29
2.48
0.28
1580
2.42
2.29
2.48
CP1
8-50
0.28
1775
0.00
0038
0.00
1404
0.06
6212
2050
0.28
1720
8.66
0.67
2.09
2.12
0.28
1720
8.61
2.10
2.13
CP1
8-57
0.28
1671
0.00
0042
0.00
0457
0.01
6633
1985
0.28
1654
4.81
0.74
2.18
2.32
0.28
1654
4.76
2.19
2.33
10-0
20.
2813
420.
0000
240.
0011
700.
0409
3623
190.
2812
90-0
.45
0.42
2.68
2.91
0.28
1290
-0.5
12.
682.
9210
-03
0.28
1213
0.00
0022
0.00
1097
0.04
0308
2626
0.28
1158
1.93
0.39
2.85
3.00
0.28
1158
1.86
2.85
3.00
10-0
50.
2815
730.
0000
740.
0012
460.
0474
1118
870.
2815
28-1
.88
1.30
2.36
2.67
0.28
1528
-1.9
22.
372.
6810
-06
0.28
1349
0.00
0048
0.00
0684
0.02
5668
2499
0.28
1316
4.63
0.84
2.63
2.73
0.28
1316
4.57
2.64
2.73
10-0
80.
2816
470.
0000
320.
0005
620.
0222
0618
770.
2816
271.
380.
562.
222.
460.
2816
271.
332.
222.
4610
-11
0.28
1315
0.00
0034
0.00
0506
0.01
5951
2469
0.28
1291
3.04
0.60
2.67
2.81
0.28
1291
2.98
2.67
2.81
10-1
20.
2815
720.
0000
440.
0011
230.
0351
5018
990.
2815
31-1
.51
0.77
2.36
2.66
0.28
1532
-1.5
52.
362.
6610
-15
0.28
1746
0.00
0060
0.00
1313
0.04
3659
1870
0.28
1699
3.80
1.05
2.13
2.30
0.28
1699
3.76
2.13
2.30
10-1
70.
2814
100.
0000
260.
0008
000.
0308
7524
350.
2813
735.
160.
462.
562.
650.
2813
735.
102.
562.
6510
-28
0.28
1537
0.00
0030
0.00
0821
0.03
0471
1967
0.28
1506
-0.8
40.
532.
392.
670.
2815
06-0
.89
2.39
2.67
10-2
90.
2816
530.
0000
500.
0012
130.
0444
3219
780.
2816
073.
000.
882.
252.
430.
2816
072.
952.
252.
44
-40-
Chapter 2 Supplementary MaterialS
uppl
emen
tary
Tab
le C
. U-P
b zi
rcon
dat
a an
d Lu
-Hf i
soto
pic
data
from
Bel
ouso
va e
t al.,
200
6
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
EG
C01
-10.
0982
40.
0022
3.73
106
0.09
090.
2754
70.
0064
0.07
564
0.00
1915
9142
1578
2015
6932
1474
3499
0.28
1697
0.00
0019
0.00
1475
0.03
9844
0.28
1653
-4.2
40.
672.
212.
59E
GC
01-2
Rim
0.10
186
0.00
213.
7795
90.
0853
0.26
911
0.00
600.
0658
40.
0015
1658
4015
8818
1536
3012
8928
93E
GC
01-5
0.09
862
0.00
203.
6885
30.
0832
0.27
126
0.00
610.
0786
60.
0017
1598
4015
6918
1547
3015
3032
970.
2817
000.
0000
150.
0007
080.
0174
480.
2816
79-3
.16
0.53
2.16
2.53
EG
C01
-60.
0975
00.
0019
3.67
456
0.07
920.
2733
40.
0060
0.06
753
0.00
1415
7738
1566
1815
5830
1321
2699
0.28
1684
0.00
0013
0.00
1123
0.02
9989
0.28
1650
-4.6
30.
462.
212.
61E
GC
01-9
0.09
762
0.00
203.
7296
90.
0839
0.27
712
0.00
620.
0816
50.
0018
1579
4015
7818
1577
3215
8634
100
EG
C01
-10
0.09
810
0.00
213.
6573
40.
0851
0.27
041
0.00
620.
0787
20.
0018
1588
4015
6218
1543
3215
3234
970.
2817
410.
0000
260.
0006
150.
0160
520.
2817
23-1
.83
0.91
2.10
2.44
EG
C01
-11
0.09
822
0.00
593.
7754
20.
2019
0.27
878
0.00
740.
0815
60.
0020
1591
114
1588
4215
8538
1585
3810
00.
2818
090.
0000
140.
0007
830.
0197
120.
2817
850.
470.
492.
022.
29E
GC
01-1
20.
0979
70.
0020
3.79
446
0.08
520.
2809
90.
0064
0.08
258
0.00
1815
8638
1592
1815
9632
1604
3410
10.
2817
240.
0000
180.
0009
770.
0246
560.
2816
95-2
.86
0.63
2.14
2.50
EG
C01
-13
0.09
818
0.00
213.
6614
50.
0862
0.27
064
0.00
640.
0773
50.
0017
1590
4015
6318
1544
3215
0632
970.
2817
180.
0000
200.
0006
430.
0158
560.
2816
99-2
.63
0.70
2.13
2.49
EG
C01
-14
0.09
958
0.00
223.
7273
00.
0914
0.27
162
0.00
660.
0694
10.
0016
1616
4215
7720
1549
3413
5630
960.
2817
450.
0000
180.
0006
930.
0182
520.
2817
24-1
.15
0.63
2.10
2.42
EG
C01
-15
0.09
784
0.00
193.
7384
60.
0821
0.27
718
0.00
620.
0818
00.
0017
1583
3815
8018
1577
3215
8932
100
0.28
1725
0.00
0014
0.00
0979
0.02
4416
0.28
1696
-2.8
90.
492.
142.
50E
GC
01-2
00.
0983
10.
0021
3.76
024
0.08
770.
2774
80.
0065
0.07
951
0.00
1815
9240
1584
1815
7932
1546
3499
EG
C01
-21
0.10
125
0.00
223.
8944
10.
0946
0.27
915
0.00
660.
0770
30.
0019
1647
4216
1320
1587
3415
0036
960.
2817
010.
0000
180.
0005
420.
0133
180.
2816
84-1
.86
0.63
2.15
2.49
EG
C01
-23
0.10
554
0.00
224.
4153
50.
1024
0.30
363
0.00
720.
0865
70.
0019
1724
3817
1520
1709
3616
7836
990.
2815
920.
0000
470.
0005
590.
0132
260.
2815
74-4
.03
1.65
2.30
2.68
EG
C01
-29
0.09
735
0.00
263.
7200
90.
1074
0.27
725
0.00
710.
0717
60.
0022
1574
5215
7624
1577
3614
0142
100
0.28
1749
0.00
0017
0.00
0470
0.01
1406
0.28
1735
-1.7
00.
602.
082.
42E
GC
01-3
00.
0973
60.
0021
3.76
628
0.09
260.
2807
00.
0068
0.07
377
0.00
1715
7442
1586
2015
9534
1439
3210
10.
2818
030.
0000
180.
0006
720.
0177
360.
2817
830.
000.
632.
022.
31E
GC
01-3
10.
0979
00.
0020
3.72
373
0.08
700.
2760
10.
0064
0.07
824
0.00
1715
8540
1576
1815
7132
1523
3299
EG
C01
-35
0.17
805
0.00
3712
.407
910.
2836
0.50
565
0.01
180.
1330
90.
0028
2635
3426
3622
2638
5025
2550
100
0.28
1128
0.00
0012
0.00
0215
0.00
4688
0.28
1117
0.62
0.42
2.90
3.09
EG
C01
-41
0.09
771
0.00
223.
7824
10.
0928
0.28
064
0.00
660.
0767
70.
0019
1581
4415
8920
1595
3414
9536
101
0.28
1759
0.00
0021
0.00
0608
0.01
5076
0.28
1741
-1.3
40.
742.
072.
40E
GC
01-4
20.
1039
40.
0022
3.87
538
0.09
190.
2704
80.
0063
0.07
360
0.00
1616
9640
1609
2015
4332
1435
3091
0.28
1796
0.00
0017
0.00
0694
0.01
6981
0.28
1774
2.44
0.60
2.03
2.25
EG
C01
-43
0.09
747
0.00
233.
7245
80.
0956
0.27
728
0.00
680.
0665
90.
0016
1576
4415
7720
1578
3413
0332
100
0.28
1763
0.00
0022
0.00
0682
0.01
7598
0.28
1743
-1.3
90.
772.
072.
40E
GC
01-4
40.
0984
90.
0021
3.73
822
0.08
670.
2752
70.
0062
0.08
370
0.00
2015
9642
1580
1815
6732
1625
3698
0.28
1831
0.00
0015
0.00
0810
0.01
9875
0.28
1807
1.33
0.53
1.99
2.24
EG
C01
-46
0.09
916
0.00
213.
7468
80.
0868
0.27
406
0.00
620.
0814
90.
0019
1608
4215
8118
1561
3215
8336
970.
2817
330.
0000
210.
0004
540.
0110
650.
2817
19-1
.49
0.74
2.10
2.43
EG
C01
-54
0.10
182
0.00
243.
7625
20.
0959
0.26
805
0.00
650.
0742
70.
0019
1658
4415
8520
1531
3214
4836
920.
2816
850.
0000
160.
0004
120.
0097
900.
2816
72-2
.03
0.56
2.16
2.51
EG
C01
-55
0.10
152
0.00
223.
6233
20.
0855
0.25
882
0.00
600.
0620
60.
0015
1652
4215
5518
1484
3012
1728
900.
2816
350.
0000
150.
0004
260.
0103
450.
2816
22-3
.96
0.53
2.23
2.62
EG
C01
-63
0.09
730
0.00
223.
7898
20.
0916
0.28
246
0.00
640.
0835
20.
0021
1573
4415
9120
1604
3216
2138
102
0.28
1747
0.00
0015
0.00
0584
0.01
4641
0.28
1730
-1.9
20.
532.
092.
43E
GC
01-6
40.
1055
10.
0021
4.25
462
0.09
470.
2924
20.
0067
0.05
731
0.00
1317
2336
1685
1816
5434
1126
2496
0.28
1557
0.00
0021
0.00
0985
0.02
3260
0.28
1525
-5.7
90.
742.
372.
79E
GC
01-6
50.
1161
90.
0025
4.96
248
0.11
220.
3098
00.
0070
0.07
460
0.00
1718
9838
1813
2017
4034
1454
3292
0.28
1808
0.00
0019
0.00
0588
0.01
4363
0.28
1787
7.50
0.67
2.01
2.08
EG
C01
-71
0.10
595
0.00
214.
4541
50.
0985
0.30
486
0.00
690.
0880
20.
0020
1731
3817
2218
1715
3417
0538
990.
2815
980.
0000
180.
0000
120.
0003
220.
2815
98-3
.02
0.63
2.26
2.63
EG
C01
-74
0.10
255
0.00
234.
1766
00.
1006
0.29
538
0.00
680.
0903
20.
0022
1671
4216
6920
1668
3417
4840
100
EG
C01
-77
0.09
943
0.00
213.
8865
30.
0911
0.28
360
0.00
660.
0763
60.
0017
1613
4016
1118
1609
3414
8732
100
0.28
1657
0.00
0022
0.00
0706
0.01
7638
0.28
1635
-4.3
50.
772.
222.
62E
GC
01-7
80.
1054
30.
0024
4.40
907
0.10
720.
3034
10.
0071
0.08
738
0.00
2117
2242
1714
2017
0836
1693
4099
0.28
1748
0.00
0016
0.00
0394
0.00
9967
0.28
1735
1.66
0.56
2.08
2.32
EG
C01
-80
0.09
841
0.00
263.
8202
30.
1101
0.28
167
0.00
730.
0653
40.
0020
1594
5015
9724
1600
3612
7938
100
0.28
1897
0.00
0019
0.00
0942
0.02
2190
0.28
1869
3.49
0.67
1.90
2.10
EG
C01
-87
0.15
597
0.00
319.
4471
00.
2157
0.43
905
0.01
040.
0760
00.
0015
2412
3423
8220
2346
4614
8128
970.
2813
000.
0000
190.
0006
610.
0158
740.
2812
700.
890.
672.
702.
90E
GC
01-8
80.
0994
00.
0021
3.57
168
0.07
840.
2607
40.
0057
0.07
107
0.00
1516
1340
1543
1814
9430
1388
3093
0.28
1673
0.00
0017
0.00
1930
0.05
4608
0.28
1614
-5.1
10.
602.
272.
67E
GC
01-9
00.
1023
40.
0021
3.76
841
0.08
280.
2671
30.
0059
0.03
343
0.00
0716
6738
1586
1815
2630
665
1492
0.28
1805
0.00
0019
0.00
0861
0.02
1440
0.28
1778
1.92
0.67
2.03
2.26
EG
C01
-92
0.09
733
0.00
213.
7128
80.
0875
0.27
661
0.00
640.
0777
00.
0017
1574
4215
7418
1574
3215
1232
100
0.28
1787
0.00
0021
0.00
0694
0.01
7350
0.28
1766
-0.5
90.
742.
042.
35E
GC
01-9
30.
1001
10.
0022
3.85
022
0.08
850.
2790
30.
0063
0.08
431
0.00
1916
2642
1603
1815
8632
1636
3698
0.28
1767
0.00
0013
0.00
0485
0.01
1742
0.28
1752
0.08
0.46
2.06
2.35
EG
C02
-60.
1125
30.
0023
5.00
283
0.09
290.
3227
20.
0061
0.08
449
0.00
1818
4138
1820
1618
0330
1639
3498
0.28
1500
0.00
0013
0.00
0667
0.01
6178
0.28
1477
-4.8
10.
462.
432.
82E
GC
02-1
80.
0965
90.
0038
3.75
125
0.12
800.
2816
70.
0056
0.08
255
0.00
1615
5976
1582
2816
0028
1603
3010
30.
2817
480.
0000
140.
0005
150.
0123
820.
2817
33-2
.12
0.49
2.08
2.43
EG
C02
-34
0.10
366
0.00
284.
3293
70.
1090
0.30
284
0.00
620.
0887
30.
0027
1691
5216
9920
1705
3017
1850
101
0.28
1509
0.00
0025
0.00
0360
0.00
8467
0.28
1497
-7.4
80.
882.
402.
88E
GC
02-3
70.
1682
20.
0050
11.2
5212
0.30
350.
4858
90.
0108
0.15
212
0.00
4825
4050
2544
2625
5348
2862
8410
10.
2809
680.
0000
190.
0003
290.
0087
790.
2809
52-7
.45
0.67
3.12
3.53
EG
C02
-38
0.11
553
0.00
225.
5172
30.
0955
0.34
614
0.00
640.
1026
10.
0019
1888
3419
0314
1916
3019
7434
101
0.28
1445
0.00
0019
0.00
0723
0.01
8181
0.28
1419
-5.7
90.
672.
512.
92E
GC
02-5
30.
1060
80.
0028
4.21
107
0.10
040.
2881
70.
0057
0.08
573
0.00
2117
3348
1676
2016
3228
1663
4094
0.28
1552
0.00
0030
0.00
0667
0.01
6361
0.28
1530
-5.3
71.
052.
362.
78E
GC
02-5
40.
1581
60.
0042
9.57
594
0.18
310.
4391
20.
0080
0.12
248
0.00
2324
3646
2395
1823
4736
2335
4296
0.28
1182
0.00
0013
0.00
0051
0.00
1525
0.28
1180
-1.7
50.
462.
823.
09E
GC
02-6
10.
1514
30.
0028
8.87
483
0.13
640.
4256
40.
0071
0.12
145
0.00
2023
6232
2325
1422
8632
2317
3697
0.28
1130
0.00
0013
0.00
1318
0.03
3921
0.28
1071
-7.3
30.
462.
983.
39E
GC
02-6
60.
1114
50.
0022
4.94
232
0.10
360.
3216
30.
0069
0.09
653
0.00
2018
2336
1810
1817
9834
1863
3899
0.28
1800
0.00
0015
0.00
1114
0.02
9097
0.28
1761
4.89
0.53
2.05
2.19
EG
C02
-70
0.17
810
0.00
3512
.221
520.
2667
0.49
769
0.01
120.
1418
10.
0030
2635
3426
2220
2604
4826
8054
990.
2810
900.
0000
140.
0002
730.
0069
190.
2810
76-0
.83
0.49
2.95
3.18
EG
C02
-81
0.11
009
0.00
224.
8202
10.
1141
0.31
759
0.00
760.
0928
90.
0021
1801
3817
8820
1778
3817
9538
990.
2816
120.
0000
170.
0005
510.
0128
880.
2815
93-1
.59
0.60
2.27
2.59
EG
C03
-10
0.16
778
0.00
3510
.246
190.
2360
0.44
296
0.01
020.
1124
00.
0027
2536
3624
5722
2364
4621
5348
930.
2813
350.
0000
220.
0012
920.
0408
940.
2812
723.
860.
772.
702.
81E
GC
03-2
00.
1740
60.
0035
10.7
8940
0.25
280.
4496
40.
0107
0.04
348
0.00
1025
9734
2505
2223
9448
860
2092
0.28
1212
0.00
0022
0.00
2834
0.11
1313
0.28
1071
-1.8
90.
772.
993.
22E
GC
03-2
40.
0998
00.
0020
3.82
295
0.08
470.
2778
30.
0062
0.08
042
0.00
1716
2038
1598
1815
8032
1563
3298
0.28
1813
0.00
0014
0.00
0606
0.01
9509
0.28
1794
1.45
0.49
2.00
2.25
-41-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
EG
C03
-34
0.16
871
0.00
3410
.069
460.
2148
0.43
297
0.00
940.
1132
60.
0024
2545
3424
4120
2319
4221
6944
910.
2812
010.
0000
110.
0004
340.
0147
400.
2811
800.
770.
392.
823.
01E
GC
03-3
50.
0999
20.
0021
3.70
098
0.08
200.
2686
80.
0059
0.04
645
0.00
1016
2340
1572
1815
3430
918
2095
0.28
1767
0.00
0017
0.00
0882
0.03
0186
0.28
1740
-0.4
20.
602.
082.
38E
GC
03-4
10.
0972
10.
0020
3.55
584
0.08
340.
2652
60.
0062
0.07
850
0.00
1815
7140
1540
1815
1732
1527
3497
0.28
1609
0.00
0017
0.00
0459
0.01
5641
0.28
1595
-6.7
30.
602.
272.
74E
GC
03-4
20.
0995
50.
0021
3.67
590
0.08
790.
2677
20.
0063
0.07
997
0.00
1916
1640
1566
2015
2932
1555
3695
0.28
1821
0.00
0020
0.00
0608
0.02
0471
0.28
1802
1.64
0.70
1.99
2.24
EG
C03
-45
0.09
786
0.00
213.
5981
60.
0876
0.26
660
0.00
630.
0801
00.
0020
1584
4215
4920
1524
3215
5738
960.
2817
420.
0000
230.
0004
970.
0166
160.
2817
27-1
.76
0.81
2.09
2.43
EG
C03
-46
0.10
484
0.00
214.
3457
40.
0979
0.30
058
0.00
700.
0896
80.
0020
1712
3617
0218
1694
3417
3638
990.
2816
320.
0000
170.
0001
320.
0048
650.
2816
28-2
.38
0.60
2.22
2.57
EG
C03
-47
0.09
934
0.00
203.
7972
10.
0879
0.27
722
0.00
650.
0808
90.
0018
1612
3815
9218
1577
3215
7232
980.
2817
080.
0000
200.
0008
150.
0279
910.
2816
83-2
.68
0.70
2.16
2.51
EG
C03
-49
0.09
725
0.00
213.
5745
70.
0848
0.26
657
0.00
620.
0806
00.
0019
1572
4015
4418
1523
3215
6736
970.
2817
470.
0000
200.
0004
870.
0161
630.
2817
33-1
.84
0.70
2.08
2.43
EG
C03
-56
0.11
222
0.00
234.
8282
50.
1155
0.31
206
0.00
740.
0825
30.
0021
1836
3817
9020
1751
3616
0340
950.
2816
420.
0000
140.
0007
470.
0255
030.
2816
160.
020.
492.
242.
51E
GC
03-6
30.
1648
20.
0034
10.4
7338
0.26
190.
4608
70.
0119
0.08
981
0.00
2125
0636
2478
2424
4352
1738
3897
0.28
1246
0.00
0016
0.00
1568
0.06
7041
0.28
1171
-0.4
50.
562.
843.
06E
GC
03-7
10.
1587
90.
0032
9.79
633
0.22
380.
4475
80.
0105
0.12
552
0.00
2824
4334
2416
2223
8446
2390
5098
0.28
1230
0.00
0012
0.00
0772
0.02
4946
0.28
1194
-1.0
80.
422.
803.
05E
GC
03-7
80.
1071
00.
0021
4.24
794
0.09
720.
2877
60.
0067
0.08
403
0.00
1817
5138
1683
1816
3034
1631
3493
0.28
1734
0.00
0011
0.00
1056
0.03
4689
0.28
1699
1.03
0.39
2.13
2.38
EG
C03
-94
0.16
443
0.00
3210
.392
480.
2443
0.45
839
0.01
110.
1168
20.
0025
2502
3424
7022
2432
4822
3346
970.
2812
740.
0000
170.
0007
890.
0270
430.
2812
361.
790.
602.
752.
91E
GC
03-9
80.
1163
60.
0023
5.35
888
0.12
430.
3339
80.
0080
0.09
081
0.00
2019
0136
1878
2018
5838
1757
3698
0.28
1415
0.00
0016
0.00
0219
0.00
9212
0.28
1407
-5.9
20.
562.
522.
94E
GC
04-5
0.15
922
0.00
329.
5949
50.
2147
0.43
699
0.00
980.
1248
90.
0028
2447
3623
9720
2337
4423
7950
960.
2811
520.
0000
140.
0006
880.
0235
990.
2811
20-3
.62
0.49
2.90
3.22
EG
C04
-60.
1053
40.
0022
4.32
882
0.10
330.
2979
70.
0070
0.07
823
0.00
1717
2040
1699
2016
8134
1522
3298
0.28
1501
0.00
0018
0.00
0794
0.02
7056
0.28
1475
-7.6
20.
632.
442.
91E
GC
04-8
0.15
487
0.00
709.
4077
80.
3538
0.44
057
0.01
100.
1231
40.
0030
2400
7823
7934
2353
5023
4754
980.
2810
860.
0000
120.
0007
580.
0254
430.
2810
51-7
.14
0.42
3.00
3.40
EG
C04
-10
0.15
111
0.00
309.
0018
20.
2063
0.43
205
0.01
000.
1238
90.
0028
2359
3423
3820
2315
4623
6150
980.
2812
450.
0000
150.
0002
900.
0090
330.
2812
32-1
.66
0.53
2.75
3.02
EG
C04
-11
0.16
125
0.00
3210
.283
660.
2342
0.46
245
0.01
060.
1327
40.
0030
2469
3424
6122
2450
4625
1952
990.
2811
390.
0000
190.
0008
790.
0316
210.
2810
98-3
.91
0.67
2.93
3.25
EG
C04
-16
0.10
872
0.00
224.
8655
10.
1153
0.32
483
0.00
790.
0919
40.
0020
1778
3817
9620
1813
3817
7838
102
0.28
1542
0.00
0024
0.00
0886
0.02
6498
0.28
1512
-4.9
90.
842.
392.
79E
GC
04-1
70.
1600
50.
0032
10.1
0623
0.24
140.
4581
30.
0111
0.12
236
0.00
2624
5634
2445
2224
3150
2333
4899
0.28
1097
0.00
0019
0.00
0410
0.01
3229
0.28
1078
-4.9
10.
672.
963.
30E
GC
04-1
90.
1920
30.
0038
12.6
6748
0.28
250.
4784
90.
0109
0.13
402
0.00
2927
6034
2655
2025
2148
2542
5291
0.28
0959
0.00
0011
0.00
0920
0.03
0011
0.28
0910
-3.8
40.
393.
183.
47E
GC
04-2
00.
1589
80.
0032
9.77
454
0.22
720.
4459
80.
0105
0.12
148
0.00
2724
4534
2414
2223
7746
2317
4897
0.28
1097
0.00
0016
0.00
0775
0.02
4730
0.28
1061
-5.7
70.
562.
983.
35E
GC
04-2
10.
1060
80.
0023
4.33
706
0.10
670.
2965
60.
0071
0.06
866
0.00
1517
3340
1700
2016
7436
1342
3097
0.28
1501
0.00
0026
0.00
0618
0.01
9792
0.28
1481
-7.1
30.
912.
432.
89E
GC
04-2
20.
1066
50.
0021
4.43
666
0.10
240.
3017
40.
0070
0.07
932
0.00
1817
4338
1719
2017
0034
1543
3498
0.28
1583
0.00
0013
0.00
0245
0.00
8084
0.28
1575
-3.5
50.
462.
292.
67E
GC
04-2
60.
1068
40.
0022
4.48
572
0.10
430.
3045
70.
0071
0.08
780
0.00
2017
4638
1728
2017
1436
1701
3698
0.28
1616
0.00
0012
0.00
0456
0.01
4214
0.28
1601
-2.5
60.
422.
262.
61E
GC
04-2
90.
1107
80.
0022
4.78
665
0.10
920.
3134
20.
0072
0.09
071
0.00
2018
1238
1783
2017
5836
1755
3697
0.28
1592
0.00
0019
0.00
0684
0.02
2529
0.28
1568
-2.2
20.
672.
312.
64E
GC
04-3
70.
1055
20.
0024
4.37
871
0.11
130.
3010
30.
0072
0.08
947
0.00
2017
2342
1708
2216
9636
1732
3898
0.28
1596
0.00
0017
0.00
0384
0.01
2311
0.28
1583
-3.7
10.
602.
282.
66E
GC
04-4
00.
1597
50.
0032
10.2
1976
0.24
970.
4641
70.
0115
0.12
942
0.00
3024
5336
2455
2224
5850
2460
5410
00.
2809
870.
0000
120.
0006
180.
0216
080.
2809
58-9
.24
0.42
3.12
3.58
EG
C04
-52
0.10
749
0.00
214.
5878
50.
1079
0.30
964
0.00
740.
0939
70.
0021
1757
3817
4720
1739
3618
1540
990.
2817
190.
0000
150.
0004
850.
0138
470.
2817
031.
310.
532.
122.
37E
GC
04-5
50.
0964
50.
0019
3.52
632
0.08
400.
2651
20.
0064
0.08
294
0.00
1915
5738
1533
1815
1632
1611
3697
0.28
1747
0.00
0011
0.00
0974
0.03
3568
0.28
1718
-2.6
80.
392.
112.
47E
GC
04-5
70.
1071
20.
0021
4.52
527
0.10
670.
3063
10.
0074
0.09
500
0.00
2217
5138
1736
2017
2336
1834
4098
0.28
1652
0.00
0016
0.00
0234
0.00
8137
0.28
1644
-0.9
10.
562.
202.
51E
GC
04-6
10.
2479
10.
0106
20.6
5480
0.67
740.
6042
70.
0166
0.16
153
0.00
4531
7170
3123
3230
4766
3027
7896
0.28
0887
0.00
0017
0.00
0896
0.02
8723
0.28
0832
2.96
0.60
3.28
3.35
EG
C04
-63
0.10
936
0.00
224.
7156
90.
1106
0.31
277
0.00
750.
0940
70.
0021
1789
3617
7020
1754
3618
1740
980.
2815
790.
0000
210.
0005
240.
0170
040.
2815
61-3
.00
0.74
2.31
2.67
EG
C04
-67
0.18
081
0.00
4112
.459
550.
3417
0.49
998
0.01
360.
1014
00.
0030
2660
3826
4026
2614
5819
5256
980.
2811
510.
0000
160.
0004
770.
0155
180.
2811
271.
540.
562.
893.
05E
GC
04-7
00.
1055
80.
0021
4.39
553
0.10
540.
3020
00.
0073
0.08
692
0.00
1917
2438
1712
2017
0136
1685
3699
0.28
1595
0.00
0016
0.00
0848
0.03
0585
0.28
1567
-4.2
60.
562.
312.
70E
GC
04-7
20.
1593
40.
0056
9.76
010
0.24
870.
4442
50.
0107
0.12
383
0.00
3124
4960
2412
2423
7048
2360
5697
0.28
1262
0.00
0017
0.00
1147
0.03
7794
0.28
1208
-0.4
30.
602.
793.
01E
GC
04-8
40.
1124
30.
0022
5.32
626
0.13
760.
3436
20.
0093
0.07
505
0.00
2318
3936
1873
2219
0444
1463
4410
40.
2815
900.
0000
150.
0014
320.
0521
680.
2815
40-2
.61
0.53
2.36
2.68
EG
C04
-86
0.16
003
0.00
3410
.246
740.
2725
0.46
494
0.01
250.
1090
50.
0037
2456
3624
5724
2461
5620
9268
100
0.28
1196
0.00
0014
0.00
0153
0.00
5015
0.28
1189
-0.9
60.
492.
803.
05E
GC
04-8
80.
1562
90.
0031
9.72
724
0.23
040.
4520
30.
0112
0.11
774
0.00
3124
1634
2409
2224
0450
2250
5610
00.
2811
040.
0000
180.
0003
580.
0117
250.
2810
88-5
.49
0.63
2.94
3.31
EG
C04
-90
0.10
511
0.00
224.
2521
60.
1059
0.29
325
0.00
730.
0796
90.
0019
1716
4016
8420
1658
3615
5034
970.
2815
060.
0000
160.
0010
450.
0333
830.
2814
72-7
.82
0.56
2.45
2.92
EG
C04
-91
0.15
556
0.00
789.
5894
60.
4008
0.44
710
0.01
220.
1249
10.
0033
2408
8623
9638
2382
5423
7960
990.
2812
170.
0000
210.
0008
260.
0283
960.
2811
79-2
.42
0.74
2.83
3.11
EG
C04
-99
0.09
713
0.00
223.
6015
30.
0946
0.26
876
0.00
680.
0736
20.
0017
1570
4415
5020
1535
3414
3632
980.
2818
060.
0000
250.
0010
700.
0360
790.
2817
74-0
.40
0.88
2.04
2.33
EG
C04
-104
0.15
569
0.00
319.
2912
90.
2351
0.43
283
0.01
170.
0682
50.
0014
2409
3423
6724
2318
5213
3426
960.
2811
400.
0000
180.
0006
240.
0265
960.
2811
11-4
.80
0.63
2.91
3.26
EG
C05
-20.
1083
80.
0022
4.68
383
0.11
440.
3133
90.
0077
0.09
825
0.00
2217
7238
1764
2017
5738
1894
4299
0.28
1669
0.00
0032
0.00
0601
0.01
6254
0.28
1649
-0.2
71.
122.
202.
48E
GC
05-3
0.10
891
0.00
224.
7233
10.
1170
0.31
449
0.00
780.
0988
60.
0023
1781
3817
7120
1763
3819
0542
990.
2815
930.
0000
190.
0009
930.
0253
000.
2815
59-3
.24
0.67
2.32
2.68
EG
C05
-50.
1143
70.
0023
5.30
477
0.13
570.
3363
80.
0086
0.10
296
0.00
2418
7038
1870
2218
6942
1981
4410
00.
2815
380.
0000
200.
0006
740.
0178
670.
2815
14-2
.83
0.70
2.38
2.72
EG
C05
-80.
0996
60.
0020
4.01
164
0.10
040.
2919
70.
0074
0.09
288
0.00
2116
1838
1637
2016
5136
1795
4010
20.
2817
850.
0000
230.
0012
150.
0334
070.
2817
48-0
.25
0.81
2.07
2.36
EG
C05
-12
0.09
926
0.00
373.
4793
20.
1003
0.25
423
0.00
620.
0743
00.
0019
1610
7215
2322
1460
3214
4936
910.
2817
070.
0000
210.
0013
330.
0377
440.
2816
66-3
.32
0.74
2.19
2.55
EG
C05
-15C
0.10
777
0.00
224.
6672
70.
1116
0.31
409
0.00
760.
1029
80.
0024
1762
3817
6120
1761
3819
8144
100
0.28
1661
0.00
0021
0.00
0625
0.01
8585
0.28
1640
-0.8
10.
742.
212.
51E
GC
05-1
5R0.
1071
00.
0022
4.65
695
0.11
180.
3153
70.
0077
0.10
070
0.00
2417
5138
1760
2017
6738
1939
4410
1E
GC
05-1
70.
1077
60.
0021
4.75
964
0.11
190.
3203
50.
0078
0.10
220
0.00
2417
6236
1778
2017
9138
1967
4410
20.
2816
710.
0000
320.
0005
180.
0126
940.
2816
54-0
.33
1.12
2.19
2.48
EG
C05
-18
0.11
238
0.00
225.
1966
70.
1219
0.33
539
0.00
810.
1064
50.
0024
1838
3618
5220
1864
4020
4544
101
EG
C05
-24
0.10
709
0.00
214.
5354
90.
1098
0.30
719
0.00
760.
1061
60.
0026
1750
3817
3820
1727
3820
3946
990.
2817
060.
0000
230.
0007
600.
0203
910.
2816
810.
360.
812.
162.
42
-42-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
EG
C05
-27
0.18
197
0.00
8411
.746
750.
4290
0.46
819
0.01
300.
1288
50.
0036
2671
7825
8434
2476
5824
5064
930.
2808
170.
0000
360.
0005
830.
0176
750.
2807
87-1
0.28
1.26
3.34
3.81
EG
C05
-31
0.10
598
0.00
214.
4480
20.
1053
0.30
443
0.00
740.
0940
70.
0021
1731
3617
2120
1713
3618
1740
990.
2815
590.
0000
260.
0006
220.
0171
170.
2815
39-5
.12
0.91
2.35
2.76
EG
C05
-33
0.11
447
0.00
245.
2986
00.
1317
0.33
575
0.00
840.
1012
90.
0025
1872
3818
6922
1866
4019
5046
100
0.28
1461
0.00
0034
0.00
0500
0.01
2616
0.28
1443
-5.3
01.
192.
472.
88E
GC
05-3
40.
1070
40.
0021
4.61
322
0.10
860.
3126
00.
0075
0.09
026
0.00
2017
5036
1752
2017
5338
1747
3810
00.
2817
210.
0000
310.
0013
100.
0340
250.
2816
780.
251.
092.
172.
43E
GC
05-3
50.
1071
30.
0021
4.60
128
0.10
690.
3115
30.
0074
0.09
243
0.00
2017
5136
1750
2017
4836
1787
3810
00.
2816
400.
0000
240.
0003
030.
0079
200.
2816
30-1
.42
0.84
2.22
2.54
EG
C05
-37
0.10
693
0.00
214.
5476
50.
1061
0.30
846
0.00
740.
0886
30.
0020
1748
3617
4020
1733
3617
1636
990.
2816
390.
0000
200.
0000
630.
0021
830.
2816
37-1
.24
0.70
2.21
2.53
EG
C05
-38
0.10
001
0.00
423.
6738
60.
1218
0.26
641
0.00
670.
0778
00.
0020
1624
8015
6626
1523
3415
1438
940.
2816
480.
0000
210.
0000
590.
0019
480.
2816
46-3
.72
0.74
2.19
2.59
EG
C05
-43
0.10
776
0.00
214.
6471
50.
1126
0.31
274
0.00
770.
0926
40.
0022
1762
3817
5820
1754
3817
9140
100
0.28
1653
0.00
0025
0.00
0425
0.01
2488
0.28
1639
-0.8
60.
882.
212.
51E
GC
05-4
40.
1022
00.
0022
4.06
027
0.10
210.
2881
50.
0071
0.08
950
0.00
2316
6440
1646
2016
3236
1733
4298
0.28
1838
0.00
0023
0.00
0727
0.01
8814
0.28
1815
3.18
0.81
1.97
2.18
EG
C05
-46C
0.11
582
0.00
245.
3700
10.
1312
0.33
623
0.00
830.
1043
10.
0024
1893
3818
8020
1869
4020
0544
990.
2814
600.
0000
140.
0011
530.
0350
540.
2814
19-5
.70
0.49
2.52
2.92
EG
CO
5-46
R0.
1154
20.
0023
5.45
061
0.13
250.
3424
50.
0085
0.09
841
0.00
2318
8636
1893
2018
9840
1897
4210
1E
GC
05-5
30.
1047
20.
0022
4.30
076
0.11
390.
2979
80.
0080
0.08
125
0.00
1917
0940
1694
2216
8140
1579
3698
0.28
1815
0.00
0018
0.00
0597
0.01
8012
0.28
1796
3.51
0.63
2.00
2.19
EG
C05
-54
0.10
607
0.00
214.
4370
50.
1107
0.30
338
0.00
770.
0850
30.
0020
1733
3817
1920
1708
3816
4936
990.
2817
840.
0000
240.
0005
420.
0164
430.
2817
663.
010.
842.
042.
24E
GC
05-5
90.
1090
50.
0022
4.77
333
0.12
000.
3174
30.
0080
0.08
621
0.00
2117
8438
1780
2217
7738
1671
4010
00.
2815
700.
0000
270.
0012
310.
0354
800.
2815
28-4
.28
0.95
2.37
2.75
EG
C05
-66
0.10
497
0.00
214.
3347
00.
1104
0.29
945
0.00
760.
0904
70.
0022
1714
3817
0022
1689
3817
5140
990.
2816
630.
0000
250.
0011
860.
0312
120.
2816
24-2
.45
0.88
2.24
2.58
EG
C05
-69
0.09
873
0.00
213.
7976
10.
0996
0.27
897
0.00
730.
0855
30.
0025
1600
4015
9222
1586
3616
5946
990.
2819
470.
0000
200.
0005
370.
0137
140.
2819
315.
830.
701.
811.
96E
GC
05-8
00.
1091
20.
0022
4.72
788
0.12
160.
3142
50.
0082
0.08
879
0.00
2217
8538
1772
2217
6240
1719
4099
0.28
1601
0.00
0022
0.00
0884
0.02
4658
0.28
1571
-2.7
40.
772.
312.
65E
GC
05-8
20.
1218
00.
0024
6.07
907
0.14
940.
3620
10.
0090
0.10
677
0.00
2519
8336
1987
2219
9242
2050
4410
00.
2814
940.
0000
250.
0006
410.
0172
830.
2814
70-1
.82
0.88
2.44
2.74
EG
C05
-84
0.10
578
0.00
214.
5403
20.
1140
0.31
132
0.00
800.
0979
80.
0024
1728
3817
3820
1747
4018
8944
101
0.28
1718
0.00
0024
0.00
0110
0.00
3186
0.28
1714
1.06
0.84
2.10
2.36
EG
C05
-86
0.12
366
0.00
246.
2794
30.
1557
0.36
831
0.00
940.
1221
10.
0029
2010
3620
1622
2021
4423
2952
101
0.28
1654
0.00
0017
0.00
0306
0.00
8409
0.28
1642
4.92
0.60
2.20
2.33
EG
C05
-87
0.10
698
0.00
224.
6053
40.
1140
0.31
225
0.00
780.
0966
60.
0024
1749
3817
5020
1752
3818
6544
100
0.28
1731
0.00
0022
0.00
0838
0.02
3306
0.28
1703
1.14
0.77
2.13
2.37
EG
C05
-88
0.11
357
0.00
235.
3568
50.
1328
0.34
227
0.00
870.
1012
30.
0025
1857
3618
7822
1898
4219
4946
102
0.28
1497
0.00
0021
0.00
1337
0.03
7794
0.28
1450
-5.4
00.
742.
482.
87E
GC
05-9
50.
1041
40.
0020
4.33
720
0.10
620.
3020
80.
0076
0.09
590
0.00
2316
9936
1700
2017
0238
1851
4210
00.
2818
380.
0000
350.
0008
600.
0238
110.
2818
103.
801.
231.
982.
17E
GC
06-1
0.11
295
0.00
225.
0481
80.
1230
0.32
418
0.00
810.
0888
10.
0021
1847
3618
2720
1810
4017
2038
980.
2816
260.
0000
360.
0006
700.
0180
900.
2816
03-0
.21
1.26
2.26
2.54
EG
C06
-40.
1921
20.
0039
12.8
9721
0.31
970.
4868
60.
0123
0.13
263
0.00
3227
6034
2672
2425
5754
2517
5893
0.28
0905
0.00
0037
0.00
0581
0.01
5412
0.28
0874
-5.1
21.
303.
233.
55E
GC
06-5
0.10
940
0.00
234.
7525
90.
1162
0.31
509
0.00
770.
0932
90.
0021
1789
3817
7720
1766
3818
0340
990.
2815
770.
0000
280.
0006
010.
0156
030.
2815
57-3
.16
0.98
2.32
2.68
EG
C06
-10
0.10
891
0.00
224.
7504
60.
1149
0.31
636
0.00
780.
0846
20.
0020
1781
3817
7620
1772
3816
4238
990.
2817
070.
0000
350.
0003
360.
0085
690.
2816
961.
601.
232.
132.
37E
GC
06-1
20.
1089
70.
0025
4.59
720
0.12
870.
3060
10.
0082
0.08
992
0.00
2417
8242
1749
2417
2140
1740
4497
0.28
1810
0.00
0037
0.00
1133
0.02
9783
0.28
1772
4.32
1.30
2.03
2.20
EG
C06
-13
0.15
179
0.00
309.
2440
50.
2290
0.44
174
0.01
130.
1144
90.
0026
2366
3423
6222
2358
5021
9146
100
0.28
1115
0.00
0030
0.00
0412
0.01
1004
0.28
1096
-6.3
21.
052.
933.
32E
GC
06-2
30.
1068
60.
0021
4.08
553
0.10
620.
2773
00.
0074
0.07
819
0.00
1817
4738
1651
2215
7838
1522
3490
0.28
1611
0.00
0038
0.00
0827
0.02
6661
0.28
1584
-3.1
51.
332.
292.
65E
GC
06-2
60.
1081
00.
0025
4.73
165
0.12
640.
3174
20.
0081
0.09
895
0.00
2717
6842
1773
2217
7740
1907
4810
10.
2817
140.
0000
150.
0005
530.
0139
400.
2816
951.
290.
532.
132.
38E
GC
06-2
70.
1060
00.
0022
4.40
065
0.10
810.
3011
70.
0074
0.09
312
0.00
2217
3238
1712
2016
9736
1800
4098
0.28
1641
0.00
0019
0.00
1113
0.03
1218
0.28
1604
-2.7
60.
672.
272.
61E
GC
06-2
80.
1063
80.
0022
4.58
992
0.11
640.
3128
10.
0079
0.09
855
0.00
2517
3838
1747
2217
5538
1900
4610
10.
2818
900.
0000
210.
0034
340.
0962
650.
2817
773.
500.
742.
052.
21E
GC
06-3
30.
1087
30.
0023
4.67
253
0.11
890.
3116
30.
0078
0.09
355
0.00
2417
7840
1762
2217
4938
1808
4698
0.28
1888
0.00
0022
0.00
2369
0.06
3383
0.28
1808
5.52
0.77
1.99
2.12
EG
C06
-34
0.12
546
0.00
856.
4624
10.
3878
0.37
359
0.01
160.
1066
10.
0032
2035
122
2041
5220
4654
2047
5810
10.
2812
320.
0000
170.
0007
570.
0213
540.
2812
03-1
0.13
0.60
2.80
3.31
EG
C06
-36
0.11
288
0.00
225.
1703
40.
1258
0.33
222
0.00
830.
0993
90.
0022
1846
3618
4820
1849
4019
1542
100
0.28
1683
0.00
0017
0.00
1327
0.03
2109
0.28
1637
0.97
0.60
2.22
2.46
EG
C06
-38
0.10
073
0.00
244.
0419
70.
1062
0.29
103
0.00
720.
0873
70.
0022
1638
4416
4322
1647
3616
9340
101
0.28
1859
0.00
0015
0.00
1045
0.02
6983
0.28
1827
3.00
0.53
1.96
2.17
EG
C06
-39
0.12
852
0.00
646.
6259
00.
2748
0.37
393
0.01
030.
1064
50.
0029
2078
9020
6336
2048
4820
4552
990.
2812
660.
0000
140.
0003
430.
0099
530.
2812
52-7
.38
0.49
2.72
3.17
EG
C06
-44
0.20
651
0.00
4015
.284
810.
3673
0.53
679
0.01
350.
1491
60.
0034
2878
3228
3322
2770
5628
1060
960.
2809
160.
0000
170.
0014
180.
0363
960.
2808
38-3
.68
0.60
3.28
3.55
EG
C06
-46
0.10
828
0.00
224.
7234
40.
1173
0.31
638
0.00
800.
0907
00.
0023
1771
3817
7120
1772
4017
5542
100
0.28
1700
0.00
0014
0.00
1056
0.02
8027
0.28
1665
0.26
0.49
2.18
2.45
EG
C06
-50
0.11
427
0.00
225.
2937
00.
1256
0.33
594
0.00
830.
1001
20.
0024
1868
3618
6820
1867
4019
2944
100
0.28
1576
0.00
0013
0.00
0362
0.00
9033
0.28
1563
-1.1
30.
462.
312.
61E
GC
06-5
20.
1240
80.
0025
6.03
419
0.14
790.
3528
50.
0088
0.10
090
0.00
2420
1636
1981
2219
4842
1943
4497
0.28
1448
0.00
0014
0.00
0962
0.02
5381
0.28
1411
-3.1
60.
492.
522.
85E
GC
06-5
40.
1000
60.
0020
3.91
564
0.09
430.
2837
70.
0070
0.07
829
0.00
2016
2538
1617
2016
1034
1524
3899
0.28
1700
0.00
0020
0.00
0570
0.01
7255
0.28
1682
-2.4
10.
702.
152.
50E
GC
06-5
50.
1081
10.
0022
4.63
612
0.11
420.
3111
30.
0078
0.09
122
0.00
2217
6838
1756
2017
4638
1764
4099
0.28
1597
0.00
0020
0.00
0734
0.02
0774
0.28
1572
-3.0
80.
702.
302.
66E
GC
06-5
80.
2059
00.
0080
14.3
0986
0.40
760.
5040
70.
0132
0.13
710
0.00
3728
7464
2770
2826
3156
2597
6692
0.28
0682
0.00
0022
0.00
0169
0.00
4519
0.28
0673
-9.6
50.
773.
493.
93E
GC
06-5
90.
1027
10.
0024
3.93
138
0.10
700.
2779
80.
0073
0.08
375
0.00
2316
7444
1620
2215
8136
1626
4294
0.28
1983
0.00
0026
0.00
2137
0.06
0278
0.28
1915
6.96
0.91
1.84
1.94
EG
C06
-63
0.13
318
0.00
267.
0689
20.
1764
0.38
508
0.00
990.
1116
90.
0027
2140
3621
2022
2100
4621
4048
980.
2814
930.
0000
210.
0007
150.
0191
240.
2814
641.
550.
742.
442.
65E
GC
06-7
00.
0984
40.
0020
3.79
370
0.09
460.
2795
10.
0070
0.08
277
0.00
2115
9540
1591
2015
8936
1607
4010
00.
2818
250.
0000
210.
0009
780.
0272
850.
2817
950.
920.
742.
002.
27E
GC
06-7
1C0.
2491
00.
0050
20.7
9168
0.51
050.
6051
40.
0154
0.15
482
0.00
4531
7932
3129
2430
5162
2909
7896
0.28
0612
0.00
0020
0.00
0809
0.02
0990
0.28
0563
-6.4
60.
703.
643.
96E
GC
06-7
1R0.
2257
80.
0097
16.7
2668
0.53
030.
5373
10.
0156
0.14
488
0.00
4330
2270
2919
3027
7266
2735
7692
EG
C06
-74
0.12
173
0.00
245.
7694
60.
1438
0.34
364
0.00
890.
0997
30.
0023
1982
3619
4222
1904
4219
2142
960.
2812
910.
0000
170.
0003
540.
0089
710.
2812
78-8
.67
0.60
2.69
3.18
EG
C06
-79
0.10
370
0.00
214.
3167
70.
1089
0.30
185
0.00
780.
0904
60.
0021
1691
3816
9720
1700
3817
5040
101
0.28
1458
0.00
0033
0.00
0745
0.02
0636
0.28
1434
-9.7
31.
162.
493.
02E
GC
06-8
00.
1062
60.
0022
4.62
700
0.12
140.
3158
20.
0084
0.09
237
0.00
2717
3638
1754
2217
6942
1786
5010
20.
2815
700.
0000
290.
0005
390.
0147
050.
2815
52-4
.52
1.02
2.33
2.72
EG
C06
-84
0.14
180
0.00
308.
1521
90.
2151
0.41
692
0.01
110.
1184
30.
0029
2249
3822
4824
2246
5022
6252
100
0.28
1261
0.00
0024
0.00
1278
0.03
3748
0.28
1206
-5.1
00.
842.
803.
16
-43-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
EG
C06
-95
0.12
357
0.00
246.
0885
30.
1494
0.35
729
0.00
910.
1112
80.
0026
2008
3619
8922
1969
4421
3346
980.
2811
790.
0000
300.
0004
050.
0123
510.
2811
64-1
2.13
1.05
2.85
3.41
EG
C06
-102
0.10
950
0.00
264.
4752
80.
1252
0.29
639
0.00
800.
1027
90.
0029
1791
4417
2624
1673
4019
7852
930.
2818
670.
0000
320.
0009
130.
0252
400.
2818
366.
811.
121.
942.
04C
HA
R05
36-2
0.10
616
0.00
224.
4641
40.
1044
0.30
511
0.00
720.
0870
80.
0019
1734
4017
2420
1717
3616
8834
990.
2815
820.
0000
350.
0006
400.
0168
350.
2815
61-4
.25
1.23
2.32
2.71
CH
AR
0536
-40.
1978
70.
0039
14.4
5891
0.32
300.
5301
20.
0124
0.14
146
0.00
3128
0932
2780
2227
4252
2674
5498
0.28
1048
0.00
0017
0.00
0655
0.01
7948
0.28
1013
0.94
0.60
3.04
3.20
CH
AR
0536
-70.
1639
40.
0033
9.41
276
0.20
670.
4158
80.
0094
0.08
515
0.00
2224
9734
2379
2022
4242
1652
4090
0.28
1214
0.00
0015
0.00
1835
0.05
7915
0.28
1127
-2.2
30.
532.
913.
17C
HA
R05
36-1
10.
1682
30.
0034
10.9
8890
0.26
350.
4736
70.
0117
0.12
079
0.00
2825
4036
2522
2225
0052
2305
5098
0.28
1258
0.00
0012
0.00
0465
0.01
2096
0.28
1235
2.63
0.42
2.74
2.89
CH
AR
0536
-15
0.16
653
0.00
3210
.961
070.
2446
0.47
710
0.01
120.
1287
70.
0027
2523
3425
2020
2515
4824
4848
100
0.28
1263
0.00
0016
0.00
1185
0.03
1664
0.28
1206
1.19
0.56
2.79
2.97
CH
AR
0536
-16
0.21
214
0.00
4116
.974
250.
3724
0.57
974
0.01
340.
1542
30.
0032
2922
3229
3322
2948
5428
9956
101
0.28
0974
0.00
0013
0.00
1246
0.03
4445
0.28
0904
-0.3
00.
463.
193.
37C
HA
R05
36-1
70.
1731
30.
0042
10.6
9381
0.30
020.
4482
10.
0123
0.09
035
0.00
2525
8842
2497
2623
8754
1748
4892
0.28
1118
0.00
0017
0.00
1470
0.04
3736
0.28
1045
-3.0
20.
603.
013.
29C
HA
R05
36-1
80.
1656
20.
0033
9.88
115
0.23
730.
4326
10.
0108
0.11
317
0.00
2525
1434
2424
2223
1748
2167
4692
0.28
1072
0.00
0015
0.00
1747
0.05
3131
0.28
0988
-6.7
60.
533.
103.
47C
HA
R05
36-1
90.
1581
40.
0033
9.97
496
0.24
810.
4569
60.
0117
0.09
403
0.00
2724
3636
2432
2224
2652
1816
5010
00.
2812
060.
0000
110.
0011
430.
0384
110.
2811
53-2
.70
0.39
2.86
3.15
CH
AR
0536
-21
0.16
612
0.00
3210
.804
160.
2386
0.47
141
0.01
090.
1290
20.
0026
2519
3425
0620
2490
4824
5346
990.
2811
430.
0000
170.
0003
420.
0098
760.
2811
27-1
.73
0.60
2.89
3.15
CH
AR
0536
-26
0.17
312
0.00
3411
.595
210.
2600
0.48
560
0.01
130.
1323
00.
0028
2588
3425
7220
2552
5025
1150
990.
2812
940.
0000
170.
0011
840.
0396
060.
2812
353.
740.
602.
752.
85C
HA
R05
36-2
80.
1518
10.
0030
8.76
791
0.19
840.
4187
80.
0099
0.11
326
0.00
2423
6634
2314
2022
5544
2169
4295
0.28
1063
0.00
0018
0.00
0628
0.01
8074
0.28
1035
-8.5
20.
633.
023.
46C
HA
R05
36-2
90.
1620
90.
0032
9.64
155
0.21
670.
4312
60.
0100
0.10
831
0.00
2324
7834
2401
2023
1146
2079
4293
0.28
1225
0.00
0015
0.00
1052
0.03
1540
0.28
1175
-0.9
40.
532.
833.
07C
HA
R05
36-3
40.
1666
30.
0033
10.0
4602
0.22
940.
4371
50.
0104
0.12
343
0.00
2625
2434
2439
2223
3846
2352
4893
0.28
1195
0.00
0016
0.00
0943
0.03
3668
0.28
1150
-0.7
90.
562.
863.
10C
HA
R05
35-0
40.
1650
40.
0033
10.0
0416
0.22
940.
4396
70.
0104
0.12
246
0.00
2625
0834
2435
2223
4946
2335
4894
0.28
1180
0.00
0016
0.00
0754
0.02
1489
0.28
1144
-1.3
60.
562.
873.
12C
HA
R05
35-0
70.
1071
60.
0028
4.34
437
0.12
060.
2940
50.
0072
0.08
399
0.00
1817
5248
1702
2216
6236
1630
3495
0.28
1512
0.00
0015
0.00
0519
0.01
4187
0.28
1495
-6.2
00.
532.
412.
84C
HA
R05
35-0
90.
1648
80.
0032
10.3
0855
0.22
470.
4535
00.
0104
0.12
867
0.00
2625
0634
2463
2024
1146
2446
4696
0.28
1207
0.00
0013
0.00
0424
0.01
4193
0.28
1187
0.11
0.46
2.81
3.02
CH
AR
0535
-10
0.17
914
0.00
6512
.079
710.
3277
0.48
906
0.01
160.
1347
90.
0033
2645
6226
1126
2567
5025
5658
970.
2812
020.
0000
180.
0007
470.
0211
080.
2811
642.
530.
632.
842.
98C
HA
R05
35-1
40.
1059
20.
0023
4.40
667
0.10
490.
3015
40.
0069
0.10
427
0.00
2217
3042
1714
2016
9934
2005
4098
0.28
1525
0.00
0015
0.00
0787
0.02
3484
0.28
1499
-6.5
40.
532.
402.
85C
HA
R05
35-1
60.
1752
10.
0036
11.6
7454
0.28
280.
4831
70.
0117
0.14
703
0.00
3326
0836
2579
2225
4150
2773
5897
0.28
1147
0.00
0024
0.00
1206
0.03
9480
0.28
1087
-1.0
80.
842.
953.
18C
HA
R05
35-1
90.
1622
30.
0069
10.0
8896
0.34
380.
4510
50.
0113
0.12
550
0.00
3224
7974
2443
3224
0050
2390
5697
0.28
1108
0.00
0013
0.00
0488
0.01
4219
0.28
1084
-2.6
30.
462.
953.
23C
HA
R05
35-2
10.
1687
00.
0034
10.7
9479
0.24
830.
4639
70.
0108
0.13
111
0.00
2725
4534
2506
2224
5748
2490
4897
0.28
1194
0.00
0018
0.00
1687
0.05
2106
0.28
1114
-3.0
00.
632.
923.
20C
HA
R05
35-2
30.
1804
20.
0068
11.6
2393
0.33
430.
4672
80.
0114
0.12
870
0.00
3226
5764
2575
2624
7250
2447
5893
CH
AR
0535
-27
0.16
925
0.00
3411
.094
330.
2486
0.47
549
0.01
080.
1327
90.
0026
2550
3425
3120
2508
4825
2046
980.
2808
600.
0000
170.
0008
970.
0257
220.
2808
14-9
.64
0.60
3.31
3.76
CH
AR
0535
-28
0.16
806
0.00
3410
.810
260.
2448
0.46
658
0.01
080.
1286
30.
0026
2538
3425
0722
2469
4824
4646
970.
2810
720.
0000
160.
0005
860.
0162
970.
2810
43-3
.97
0.56
3.00
3.32
CH
AR
0535
-31
0.17
431
0.00
4111
.507
830.
3010
0.47
885
0.01
210.
1214
90.
0040
2599
4025
6524
2522
5223
1772
970.
2815
100.
0000
150.
0005
470.
0143
540.
2814
90-1
.62
0.53
2.41
2.71
CH
AR
0535
-32
0.19
295
0.00
3813
.313
890.
3008
0.50
057
0.01
180.
0851
20.
0018
2767
3227
0222
2616
5016
5132
950.
2811
930.
0000
170.
0010
810.
0302
720.
2811
390.
580.
602.
883.
07C
HA
R02
37-0
10.
1974
60.
0239
13.4
1959
1.51
100.
4929
10.
0217
0.13
460
0.00
5228
0520
227
1010
625
8394
2552
9292
CH
AR
0237
-10
0.16
192
0.00
3210
.136
300.
2302
0.45
403
0.01
060.
1377
10.
0028
2476
3424
4720
2413
4626
0850
970.
2823
370.
0000
180.
0003
350.
0097
750.
2823
33-2
.20
0.63
1.27
1.70
CH
AR
0237
-12
0.25
460
0.00
9021
.077
400.
5462
0.60
043
0.01
430.
1601
10.
0039
3214
5631
4226
3032
5830
0268
940.
2810
540.
0000
170.
0006
370.
0177
700.
2810
24-6
.37
0.60
3.03
3.41
CH
AR
0237
-13
0.10
103
0.00
594.
1103
90.
2130
0.29
509
0.00
780.
0860
80.
0022
1643
110
1656
4216
6738
1669
4010
1C
HA
R02
37-1
60.
2512
80.
0098
21.0
3426
0.61
530.
6071
10.
0157
0.16
208
0.00
4331
9364
3140
2830
5862
3036
7696
0.28
1179
0.00
0019
0.00
0992
0.03
7798
0.28
1133
-3.0
10.
672.
893.
18C
HA
R02
37-1
70.
1597
80.
0031
9.24
604
0.20
670.
4197
60.
0098
0.10
428
0.00
2124
5334
2363
2022
5944
2005
4092
0.28
0802
0.00
0013
0.00
0951
0.02
5047
0.28
0744
0.31
0.46
3.40
3.54
CH
AR
0237
-19
0.15
579
0.00
319.
7221
10.
2308
0.45
257
0.01
110.
1255
90.
0029
2410
3424
0922
2407
5023
9152
100
0.28
1156
0.00
0013
0.00
0863
0.03
2638
0.28
1116
-3.6
40.
462.
913.
22C
HA
R02
37-2
10.
0965
50.
0087
3.73
861
0.31
770.
2808
30.
0085
0.08
231
0.00
2115
5917
415
8068
1596
4215
9940
102
CH
AR
0237
-22
0.17
041
0.00
3610
.909
670.
2533
0.46
410
0.01
090.
1301
60.
0029
2562
3625
1522
2458
4824
7352
960.
2810
790.
0000
190.
0006
620.
0248
230.
2810
49-7
.01
0.67
3.00
3.40
CH
AR
0237
-26
0.16
001
0.00
319.
9592
80.
2166
0.45
123
0.01
040.
1272
00.
0026
2456
3424
3120
2401
4624
2046
980.
2811
600.
0000
200.
0010
090.
0289
000.
2811
090.
810.
702.
923.
09C
HA
R02
37-3
20.
1635
70.
0032
10.3
2943
0.22
860.
4578
20.
0107
0.12
356
0.00
2524
9334
2465
2024
3048
2355
4697
0.28
0793
0.00
0013
0.00
1114
0.03
6216
0.28
0725
-1.0
70.
463.
423.
60C
HA
R05
37-0
80.
1674
90.
0032
9.78
629
0.21
180.
4237
10.
0097
0.08
150
0.00
1625
3334
2415
2022
7744
1584
3090
0.28
1130
0.00
0012
0.00
0555
0.02
0602
0.28
1104
-3.8
70.
422.
923.
24C
HA
R05
37-0
90.
1041
40.
0022
4.18
961
0.09
960.
2917
80.
0069
0.08
199
0.00
1716
9940
1672
2016
5034
1593
3297
0.28
1296
0.00
0029
0.00
2258
0.06
9039
0.28
1187
0.74
1.02
2.82
3.00
CH
AR
0537
-18
0.16
628
0.00
6210
.064
890.
2848
0.43
900
0.01
060.
1218
60.
0030
2521
6424
4126
2346
4823
2454
930.
2810
970.
0000
180.
0014
290.
0533
640.
2810
31-7
.29
0.63
3.03
3.43
CH
AR
0537
-27
0.16
968
0.00
3210
.202
970.
2171
0.43
614
0.00
980.
1165
10.
0022
2554
3224
5320
2333
4422
2840
910.
2811
490.
0000
170.
0005
370.
0145
030.
2811
23-1
.48
0.60
2.90
3.15
CH
AR
0909
-03
0.16
628
0.00
6410
.532
160.
3134
0.45
939
0.01
140.
1275
20.
0032
2521
6624
8328
2437
5024
2658
970.
2812
170.
0000
240.
0009
650.
0245
580.
2811
700.
630.
842.
843.
03C
HA
R09
09-0
60.
2409
90.
0100
19.2
4108
0.60
680.
5790
70.
0157
0.15
520
0.00
4331
2768
3054
3029
4564
2916
7494
0.28
1342
0.00
0018
0.00
0711
0.01
9039
0.28
1308
4.77
0.63
2.65
2.74
CH
AR
0909
-08
0.24
637
0.00
8620
.138
050.
5008
0.59
282
0.01
450.
1585
60.
0040
3162
5630
9824
3001
5829
7570
950.
2806
630.
0000
110.
0006
160.
0151
170.
2806
26-5
.42
0.39
3.55
3.85
CH
AR
0909
-14
0.16
234
0.00
329.
7782
30.
2203
0.43
691
0.01
030.
1201
80.
0027
2480
3424
1420
2337
4622
9448
940.
2823
440.
0000
170.
0012
060.
0348
580.
2823
1610
.74
0.60
1.29
1.34
CH
AR
0909
-16
0.17
433
0.00
3611
.089
510.
2656
0.46
148
0.01
130.
1295
50.
0034
2600
3625
3122
2446
5024
6262
940.
2812
240.
0000
160.
0004
870.
0166
110.
2812
010.
020.
562.
793.
01C
HA
R09
09-2
20.
1604
00.
0034
10.1
7293
0.24
760.
4601
50.
0114
0.13
789
0.00
3124
6036
2451
2224
4050
2611
5499
0.28
1224
0.00
0015
0.00
1033
0.03
2993
0.28
1173
1.79
0.53
2.83
2.99
CH
AR
0909
-29
0.16
266
0.00
3210
.325
740.
2312
0.46
048
0.01
070.
1394
20.
0031
2483
3424
6420
2442
4826
3856
980.
2820
830.
0000
120.
0013
930.
0401
310.
2820
55-1
.89
0.42
1.66
2.03
CH
AR
0909
-32
0.10
509
0.00
254.
3681
70.
1101
0.30
148
0.00
710.
0963
90.
0024
1716
4417
0620
1699
3418
6044
990.
2811
520.
0000
130.
0004
790.
0112
180.
2811
29-2
.46
0.46
2.89
3.17
CH
AR
0909
-35
0.16
772
0.00
3910
.917
660.
2859
0.47
231
0.01
210.
1419
40.
0033
2535
4025
1624
2494
5426
8358
980.
2816
920.
0000
160.
0006
270.
0169
340.
2816
72-0
.73
0.56
2.17
2.47
CH
AR
0909
-36
0.15
848
0.00
349.
9835
30.
2277
0.45
695
0.01
040.
1360
90.
0041
2440
3624
3322
2426
4625
7974
990.
2811
260.
0000
190.
0012
730.
0357
810.
2810
64-3
.57
0.67
2.98
3.28
-44-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
TOD
1-2
0.10
562
0.00
234.
5516
70.
1044
0.31
285
0.00
690.
0913
00.
0019
1725
4017
4020
1755
3417
6636
102
0.28
1230
0.00
0021
0.00
0576
0.01
6320
0.28
1203
-0.8
20.
742.
793.
03TO
D1-
40.
1145
90.
0023
5.34
932
0.12
030.
3389
70.
0077
0.09
571
0.00
2018
7338
1877
2018
8236
1847
3610
00.
2816
510.
0000
160.
0002
750.
0064
960.
2816
42-1
.58
0.56
2.20
2.53
TOD
1-5
0.10
643
0.00
224.
5735
60.
1058
0.31
201
0.00
710.
0920
90.
0020
1739
3817
4420
1751
3617
8136
101
0.28
1632
0.00
0016
0.00
0974
0.02
5592
0.28
1597
0.20
0.56
2.27
2.53
TOD
1-6
0.16
008
0.00
379.
9862
40.
2533
0.45
300
0.01
050.
1299
70.
0030
2457
4024
3424
2409
4624
7054
980.
2816
320.
0000
160.
0010
350.
0229
460.
2815
98-2
.83
0.56
2.27
2.62
TOD
1-6B
0.15
810
0.00
349.
9704
60.
2372
0.45
768
0.01
050.
1301
30.
0029
2435
3824
3222
2429
4624
7352
100
TOD
1-7
0.12
225
0.00
265.
9079
00.
1368
0.35
092
0.00
780.
1026
90.
0022
1989
3819
6220
1939
3819
7640
970.
2811
480.
0000
160.
0002
580.
0064
930.
2811
36-2
.82
0.56
2.88
3.17
TOD
1-9
0.11
292
0.00
245.
2562
70.
1233
0.33
793
0.00
780.
0949
10.
0021
1847
3818
6220
1877
3818
3338
102
0.28
1449
0.00
0017
0.00
0982
0.02
7667
0.28
1412
-3.7
50.
602.
522.
87TO
D1-
100.
1136
10.
0024
5.21
728
0.12
240.
3333
40.
0077
0.09
243
0.00
2018
5838
1855
2018
5538
1787
3810
00.
2817
220.
0000
270.
0004
480.
0113
830.
2817
063.
470.
952.
122.
30TO
D1-
110.
1072
30.
0022
4.59
399
0.10
610.
3109
80.
0070
0.09
276
0.00
2017
5340
1748
2017
4634
1793
3610
00.
2816
130.
0000
130.
0008
290.
0228
950.
2815
84-0
.63
0.46
2.29
2.57
TOD
1-13
0.20
059
0.00
7113
.808
560.
3620
0.49
928
0.01
210.
1361
40.
0034
2831
6027
3724
2611
5225
8060
920.
2816
720.
0000
200.
0007
240.
0198
990.
2816
446.
180.
702.
202.
29TO
D1-
150.
1060
30.
0021
4.62
534
0.10
650.
3164
20.
0073
0.09
742
0.00
2217
3238
1754
2017
7236
1879
4210
20.
2809
090.
0000
220.
0008
780.
0226
870.
2808
61-3
.94
0.77
3.25
3.53
TOD
1-16
0.12
337
0.00
266.
2255
60.
1556
0.36
598
0.00
910.
1082
80.
0030
2006
3820
0822
2010
4420
7854
100
0.28
1757
0.00
0022
0.00
0360
0.01
0932
0.28
1745
2.24
0.77
2.06
2.29
TOD
1-17
0.11
188
0.00
225.
0631
40.
1230
0.32
821
0.00
810.
1074
40.
0025
1830
3618
3020
1830
4020
6346
100
0.28
1376
0.00
0021
0.00
0529
0.01
6578
0.28
1356
-5.3
50.
742.
592.
99TO
D1-
180.
1153
40.
0024
5.32
074
0.13
450.
3345
70.
0084
0.09
125
0.00
2318
8538
1872
2218
6040
1765
4299
0.28
1553
0.00
0023
0.00
1210
0.03
5172
0.28
1511
-3.8
50.
812.
392.
75TO
D1-
19A
0.10
572
0.00
224.
6129
90.
1162
0.31
644
0.00
790.
0925
20.
0023
1727
4017
5222
1772
3817
8942
103
TOD
1-19
B0.
1073
90.
0022
4.74
550
0.10
780.
3205
10.
0072
0.09
945
0.00
2317
5638
1775
2017
9236
1916
4210
20.
2816
710.
0000
200.
0012
570.
0375
190.
2816
261.
490.
702.
232.
46TO
D1-
230.
1122
20.
0022
5.15
288
0.12
240.
3330
30.
0080
0.10
182
0.00
2418
3636
1845
2018
5338
1960
4410
10.
2818
090.
0000
250.
0017
220.
0477
450.
2817
57-0
.15
0.88
2.07
2.35
TOD
1-25
0.23
658
0.00
4619
.548
650.
4473
0.59
929
0.01
400.
1665
20.
0038
3097
3230
6922
3027
5631
1366
980.
2816
530.
0000
190.
0006
380.
0209
650.
2816
310.
540.
672.
222.
48TO
D1-
260.
1125
70.
0048
5.00
792
0.17
310.
3226
50.
0079
0.09
308
0.00
2318
4178
1821
3018
0338
1799
4298
0.28
0825
0.00
0015
0.00
0810
0.02
3490
0.28
0777
-0.7
50.
533.
353.
53TO
D1-
270.
1065
90.
0022
4.44
902
0.11
030.
3027
60.
0075
0.07
164
0.00
1817
4238
1722
2017
0538
1398
3498
0.28
1619
0.00
0023
0.00
0571
0.01
7446
0.28
1599
-0.4
70.
812.
262.
55TO
D1-
280.
1254
40.
0025
6.13
230
0.14
420.
3545
60.
0084
0.10
319
0.00
2420
3536
1995
2019
5640
1985
4496
0.28
1596
0.00
0018
0.00
0654
0.02
4065
0.28
1574
-3.5
90.
632.
302.
67TO
D1-
300.
1055
10.
0052
4.45
292
0.18
950.
3061
00.
0078
0.08
889
0.00
2217
2394
1722
3617
2138
1721
4210
00.
2813
930.
0000
170.
0008
990.
0284
780.
2813
58-4
.60
0.60
2.59
2.96
TOD
1-31
0.10
642
0.00
214.
5407
10.
1037
0.30
944
0.00
710.
0935
30.
0022
1739
3817
3820
1738
3418
0740
100
0.28
1893
0.00
0021
0.00
2041
0.06
1160
0.28
1826
4.92
0.74
1.96
2.11
TOD
1-32
0.12
208
0.00
256.
0421
00.
1391
0.35
897
0.00
830.
1091
20.
0026
1987
3619
8220
1977
4020
9348
990.
2813
640.
0000
190.
0000
650.
0020
100.
2813
62-1
1.21
0.67
2.58
3.15
TOD
1-33
0.10
906
0.00
534.
8592
90.
2011
0.32
316
0.00
820.
0935
30.
0024
1784
9017
9534
1805
4018
0744
101
0.28
1386
0.00
0022
0.00
1414
0.04
1016
0.28
1333
-6.6
10.
772.
643.
05TO
D1-
370.
1246
70.
0025
6.08
941
0.13
680.
3542
80.
0081
0.08
372
0.00
1920
2436
1989
2019
5538
1625
3497
0.28
1319
0.00
0021
0.00
4073
0.14
5403
0.28
1115
0.18
0.74
2.93
3.11
TOD
1-42
A0.
1066
30.
0022
4.54
770
0.11
430.
3093
20.
0078
0.08
310
0.00
2117
4338
1740
2017
3738
1613
3810
00.
2813
780.
0000
180.
0005
300.
0149
100.
2813
58-4
.87
0.63
2.59
2.97
TOD
1-42
B0.
1981
50.
0040
14.6
1042
0.35
870.
5347
80.
0133
0.13
718
0.00
3528
1134
2790
2427
6256
2598
6298
0.28
1627
0.00
0018
0.00
0367
0.00
8335
0.28
1615
-2.1
40.
632.
242.
58TO
D1-
460.
1130
40.
0025
5.26
959
0.14
010.
3381
30.
0088
0.09
834
0.00
2718
4940
1864
2218
7842
1896
4810
20.
2813
700.
0000
220.
0011
460.
0392
170.
2813
25-5
.34
0.77
2.64
3.02
TOD
1-47
0.12
673
0.00
256.
2385
70.
1511
0.35
707
0.00
880.
0547
10.
0013
2053
3620
1022
1968
4210
7724
960.
2816
680.
0000
210.
0008
490.
0230
380.
2816
381.
100.
742.
212.
45TO
D1-
480.
1229
40.
0026
6.39
965
0.16
400.
3775
60.
0096
0.10
355
0.00
2619
9938
2032
2220
6546
1992
4810
30.
2814
150.
0000
210.
0007
430.
0219
210.
2813
86-3
.20
0.74
2.55
2.89
TOD
1-49
0.12
353
0.00
266.
1992
10.
1496
0.36
399
0.00
880.
1081
10.
0026
2008
3820
0422
2001
4220
7548
100
0.28
1438
0.00
0028
0.00
0997
0.02
9028
0.28
1400
-3.9
30.
982.
542.
89TO
D1-
530.
1165
20.
0023
5.48
798
0.12
900.
3416
20.
0082
0.09
111
0.00
2119
0436
1899
2018
9440
1762
4099
0.28
1304
0.00
0020
0.00
0643
0.01
9386
0.28
1279
-8.0
20.
702.
693.
16TO
D1-
600.
1247
40.
0025
6.42
317
0.15
520.
3735
00.
0091
0.10
768
0.00
2620
2536
2035
2220
4642
2067
4810
10.
2817
370.
0000
210.
0005
310.
0143
710.
2817
185.
180.
742.
102.
24TO
D1-
610.
2423
40.
0049
20.3
5279
0.48
920.
6091
60.
0148
0.16
481
0.00
4031
3532
3108
2430
6760
3084
7098
0.28
1397
0.00
0013
0.00
0501
0.01
6222
0.28
1378
-4.1
40.
462.
562.
92TO
D1-
620.
1075
90.
0022
4.49
711
0.11
050.
3031
70.
0075
0.07
047
0.00
1917
5938
1730
2017
0736
1376
3697
0.28
0772
0.00
0018
0.00
0348
0.00
9903
0.28
0751
-0.7
80.
633.
383.
56TO
D1-
650.
1072
50.
0022
4.65
522
0.11
280.
3148
10.
0076
0.09
442
0.00
2217
5338
1759
2017
6438
1824
4210
10.
2815
490.
0000
240.
0000
910.
0024
950.
2815
46-4
.22
0.84
2.33
2.72
TOD
1-70
0.23
236
0.00
4619
.158
370.
4559
0.59
797
0.01
450.
1631
10.
0039
3068
3230
5022
3022
5830
5468
990.
2810
960.
0000
190.
0005
100.
0132
680.
2810
79-2
0.93
0.67
2.96
3.77
TOD
1-70
B0.
1326
50.
0027
6.95
879
0.17
960.
3805
10.
0098
0.09
989
0.00
2821
3336
2106
2220
7946
1924
5297
0.28
0797
0.00
0021
0.00
0496
0.01
1895
0.28
0768
-1.7
50.
743.
363.
57TO
D1-
710.
1235
30.
0025
6.30
547
0.15
030.
3702
10.
0089
0.10
707
0.00
2520
0836
2019
2020
3042
2056
4610
10.
2810
470.
0000
290.
0001
870.
0044
380.
2810
39-1
3.69
1.02
3.01
3.61
TOD
1-85
0.11
624
0.00
235.
2232
00.
1238
0.32
588
0.00
780.
0941
90.
0023
1899
3618
5620
1818
3818
1942
960.
2813
550.
0000
190.
0011
330.
0327
780.
2813
12-6
.87
0.67
2.66
3.08
TOD
1-87
0.23
397
0.00
4619
.232
330.
4704
0.59
622
0.01
480.
1656
50.
0040
3079
3230
5424
3015
6030
9870
980.
2817
250.
0000
260.
0005
880.
0155
700.
2817
044.
570.
912.
122.
27TO
D1-
940.
1153
50.
0023
5.37
634
0.13
120.
3380
80.
0083
0.09
201
0.00
2318
8538
1881
2018
7740
1779
4210
00.
2808
580.
0000
170.
0017
010.
0464
030.
2807
57-1
.86
0.60
3.39
3.59
TOD
1-99
0.10
433
0.00
214.
3919
40.
1070
0.30
532
0.00
740.
0914
20.
0022
1703
3817
1120
1718
3617
6840
101
0.28
1534
0.00
0024
0.00
1138
0.03
4535
0.28
1493
-3.2
20.
842.
412.
76TO
D1-
103
0.11
377
0.00
245.
2502
20.
1294
0.33
474
0.00
820.
1022
00.
0027
1860
3818
6122
1861
4019
6748
100
0.28
1523
0.00
0021
0.00
0757
0.02
3329
0.28
1499
-7.1
70.
742.
412.
87TO
D2-
20.
1251
00.
0025
6.10
926
0.14
080.
3542
80.
0082
0.09
896
0.00
2320
3036
1992
2019
5538
1907
4296
0.28
1685
0.00
0021
0.00
1012
0.02
8968
0.28
1649
1.75
0.74
2.20
2.42
TOD
2-3
0.12
537
0.00
256.
3249
90.
1401
0.36
607
0.00
810.
1087
90.
0024
2034
3620
2220
2011
3820
8744
990.
2813
800.
0000
150.
0004
520.
0127
110.
2813
63-4
.56
0.53
2.58
2.95
TOD
2-4
0.12
541
0.00
266.
2490
50.
1429
0.36
165
0.00
820.
1052
80.
0024
2035
3820
1120
1990
3820
2344
980.
2814
560.
0000
140.
0003
700.
0103
480.
2814
42-1
.66
0.49
2.47
2.77
TOD
2-5
0.12
493
0.00
256.
2932
70.
1426
0.36
558
0.00
830.
1059
10.
0023
2028
3620
1820
2009
3820
3542
990.
2813
900.
0000
150.
0005
290.
0140
780.
2813
70-4
.20
0.53
2.57
2.93
TOD
2-6
0.12
605
0.00
266.
3401
40.
1441
0.36
513
0.00
820.
1054
50.
0024
2044
3820
2420
2006
3820
2644
980.
2812
950.
0000
130.
0006
880.
0197
250.
2812
68-7
.95
0.46
2.71
3.17
TOD
2-8
0.12
445
0.00
256.
3215
70.
1481
0.36
851
0.00
870.
1042
80.
0024
2021
3620
2120
2022
4020
0544
100
0.28
2224
0.00
0018
0.00
1013
0.02
8295
0.28
2206
0.82
0.63
1.45
1.77
TOD
2-9
0.12
474
0.00
295.
9102
60.
1548
0.34
356
0.00
860.
0086
10.
0003
2025
4219
6322
1904
4217
36
940.
2813
850.
0000
180.
0005
930.
0184
750.
2813
62-4
.78
0.63
2.58
2.96
TOD
2-10
0.10
599
0.00
224.
6346
40.
1108
0.31
727
0.00
740.
0962
80.
0024
1732
4017
5620
1776
3618
5844
103
0.28
1445
0.00
0018
0.00
1399
0.04
4956
0.28
1391
-3.6
60.
632.
552.
89TO
D2-
110.
1241
90.
0025
6.22
361
0.13
840.
3634
50.
0081
0.10
909
0.00
2420
1736
2008
2019
9938
2093
4499
0.28
1494
0.00
0023
0.00
0892
0.02
6327
0.28
1465
-7.7
20.
812.
452.
92
-45-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
TOD
2-12
0.12
479
0.00
295.
8340
80.
1395
0.33
908
0.00
760.
0764
50.
0021
2026
4219
5120
1882
3614
8940
930.
2814
410.
0000
210.
0012
900.
0395
620.
2813
92-3
.83
0.74
2.55
2.90
TOD
2-13
0.12
427
0.00
256.
1798
20.
1366
0.36
069
0.00
800.
1090
50.
0024
2018
3620
0220
1985
3820
9244
980.
2813
630.
0000
300.
0007
180.
0225
650.
2813
35-5
.62
1.05
2.62
3.02
TOD
2-14
0.11
296
0.00
235.
1570
90.
1194
0.33
114
0.00
760.
0924
00.
0022
1848
3818
4620
1844
3617
8642
100
0.28
1475
0.00
0024
0.00
1247
0.03
9982
0.28
1427
-2.5
40.
842.
502.
82TO
D2-
150.
1249
70.
0025
6.37
713
0.14
070.
3701
30.
0082
0.10
942
0.00
2420
2836
2029
2020
3038
2099
4410
00.
2816
110.
0000
200.
0008
730.
0240
190.
2815
80-0
.97
0.70
2.29
2.59
TOD
2-16
0.12
482
0.00
266.
3033
90.
1428
0.36
627
0.00
820.
1079
70.
0025
2026
3820
1920
2012
3820
7246
990.
2813
860.
0000
110.
0007
040.
0218
270.
2813
59-4
.74
0.39
2.59
2.96
TOD
2-17
0.15
316
0.00
338.
3765
30.
2077
0.39
649
0.01
000.
0690
10.
0022
2382
3822
7322
2153
4613
4942
900.
2814
430.
0000
170.
0014
320.
0487
050.
2813
88-3
.75
0.60
2.56
2.90
TOD
2-18
0.12
488
0.00
296.
0840
70.
1433
0.35
351
0.00
760.
0856
70.
0024
2027
4219
8820
1951
3616
6144
960.
2812
750.
0000
260.
0026
120.
0777
640.
2811
56-3
.82
0.91
2.88
3.18
TOD
2-19
0.12
282
0.00
286.
1442
40.
1555
0.36
291
0.00
870.
0991
80.
0027
1998
4219
9722
1996
4219
1148
100
0.28
1410
0.00
0020
0.00
0723
0.02
2175
0.28
1382
-3.9
30.
702.
562.
91TO
D2-
200.
1241
40.
0025
6.31
116
0.14
110.
3687
40.
0082
0.09
956
0.00
2220
1738
2020
2020
2338
1918
4010
0TO
D2-
210.
1164
50.
0071
5.60
530
0.30
690.
3491
10.
0093
0.10
037
0.00
2519
0211
219
1748
1930
4419
3346
101
0.28
1420
0.00
0026
0.00
0674
0.02
0096
0.28
1394
-4.1
60.
912.
542.
90TO
D2-
220.
1241
30.
0025
6.13
597
0.14
360.
3585
30.
0085
0.10
371
0.00
2420
1636
1995
2019
7540
1994
4498
0.28
1419
0.00
0018
0.00
0441
0.01
3330
0.28
1403
-6.0
40.
632.
532.
95TO
D2-
230.
1247
50.
0025
6.02
142
0.14
000.
3500
00.
0081
0.09
486
0.00
2220
2536
1979
2019
3538
1832
4096
0.28
1443
0.00
0019
0.00
1093
0.03
5819
0.28
1401
-3.5
10.
672.
542.
88TO
D2-
240.
1230
20.
0025
5.87
309
0.13
970.
3462
80.
0083
0.09
909
0.00
2320
0036
1957
2019
1740
1910
4296
0.28
1443
0.00
0019
0.00
1093
0.03
5819
0.28
1401
-3.3
10.
672.
542.
87TO
D2-
250.
1230
00.
0052
5.94
898
0.20
730.
3507
70.
0085
0.10
029
0.00
2420
0078
1968
3019
3840
1932
4497
TOD
2-26
0.16
016
0.00
339.
7060
10.
2272
0.43
948
0.01
030.
1259
20.
0029
2457
3624
0722
2348
4623
9752
960.
2814
030.
0000
140.
0009
100.
0283
860.
2813
68-5
.04
0.49
2.58
2.96
TOD
2-27
0.12
272
0.00
255.
9229
00.
1390
0.35
001
0.00
820.
1026
90.
0024
1996
3819
6520
1935
3819
7644
970.
2809
770.
0000
180.
0002
020.
0053
570.
2809
68-8
.81
0.63
3.10
3.55
TOD
2-28
0.11
194
0.00
244.
7431
50.
1248
0.30
748
0.00
810.
0338
00.
0009
1831
4017
7522
1728
4067
218
940.
2813
580.
0000
190.
0007
680.
0226
140.
2813
29-6
.53
0.67
2.63
3.05
TOD
2-29
0.12
378
0.00
256.
0459
90.
1386
0.35
431
0.00
810.
1028
40.
0023
2011
3619
8220
1955
3819
7942
97TO
D2-
300.
1239
60.
0025
5.98
168
0.13
920.
3500
20.
0082
0.09
970
0.00
2320
1436
1973
2019
3540
1921
4296
TOD
2-31
0.12
443
0.00
256.
2016
50.
1433
0.36
144
0.00
850.
1034
90.
0023
2021
3620
0520
1989
4019
9042
98TO
D2-
320.
1250
20.
0025
6.22
159
0.14
700.
3608
50.
0087
0.10
252
0.00
2320
2936
2007
2019
8642
1973
4298
TOD
2-33
0.12
495
0.00
256.
2232
70.
1457
0.36
116
0.00
860.
1043
50.
0024
2028
3620
0820
1988
4020
0644
98TO
D2-
340.
1240
30.
0025
6.17
993
0.14
440.
3612
60.
0085
0.10
447
0.00
2420
1536
2002
2019
8840
2008
4499
TOD
2-35
0.12
497
0.00
256.
2679
00.
1477
0.36
368
0.00
870.
1071
40.
0024
2028
3620
1420
2000
4220
5744
99TO
D2-
360.
1245
10.
0025
5.98
378
0.15
040.
3485
80.
0089
0.07
886
0.00
1920
2236
1973
2219
2842
1534
3695
TOD
2-37
0.12
366
0.00
256.
2752
20.
1473
0.36
792
0.00
870.
1040
30.
0024
2010
3620
1520
2020
4220
0044
100
TOD
2-38
0.12
070
0.00
256.
4524
80.
1539
0.38
754
0.00
920.
1063
50.
0026
1967
3820
3920
2111
4220
4346
107
TOD
2-39
0.12
470
0.00
256.
1030
40.
1442
0.35
472
0.00
850.
0901
40.
0020
2025
3619
9120
1957
4017
4438
97TO
D2-
400.
1246
00.
0025
5.65
202
0.13
400.
3287
90.
0078
0.08
233
0.00
1920
2336
1924
2018
3338
1599
3691
TOD
2-47
0.12
481
0.00
256.
1889
90.
1494
0.35
953
0.00
870.
1047
80.
0024
2026
3620
0322
1980
4220
1444
98TO
D2-
510.
1249
40.
0025
6.36
966
0.15
650.
3696
60.
0091
0.10
752
0.00
2620
2836
2028
2220
2842
2064
4610
0TO
D2-
580.
1215
30.
0061
5.95
927
0.25
600.
3556
50.
0095
0.10
181
0.00
2719
7992
1970
3819
6246
1960
4899
0.28
1295
0.00
0023
0.00
1070
0.02
6262
0.28
1243
3.37
0.81
2.74
2.86
TOD
2-79
0.11
172
0.00
724.
8896
30.
2854
0.31
744
0.00
900.
0916
50.
0024
1828
120
1800
5017
7744
1772
4697
0.28
1497
0.00
0014
0.00
0794
0.02
4354
0.28
1467
-2.0
10.
492.
442.
75TO
D2-
930.
1118
00.
0063
4.79
863
0.23
950.
3112
90.
0084
0.08
987
0.00
2318
2910
617
8542
1747
4217
3944
960.
2814
360.
0000
210.
0008
540.
0281
160.
2814
06-7
.61
0.74
2.53
2.99
WA
NG
-10.
1669
40.
0036
11.0
5118
0.29
990.
4802
00.
0131
0.12
506
0.00
3625
2738
2527
2625
2856
2382
6410
00.
2814
110.
0000
180.
0011
030.
0321
850.
2813
73-8
.78
0.63
2.58
3.07
WA
NG
-20.
1078
50.
0032
4.61
789
0.15
520.
3114
50.
0094
0.06
448
0.00
2717
6356
1753
2817
4846
1263
5299
0.28
1170
0.00
0015
0.00
1288
0.03
4815
0.28
1108
-2.2
10.
532.
923.
19W
AN
G-3
0.12
525
0.00
286.
0454
60.
1672
0.35
006
0.00
950.
0666
20.
0019
2032
4019
8224
1935
4613
0436
950.
2815
350.
0000
200.
0004
890.
0131
490.
2815
19-5
.10
0.70
2.37
2.78
WA
NG
-50.
1581
20.
0031
10.0
4866
0.25
850.
4609
30.
0122
0.12
536
0.00
2924
3634
2439
2424
4454
2387
5210
00.
2814
040.
0000
150.
0004
630.
0129
380.
2813
86-3
.68
0.53
2.55
2.90
WA
NG
-60.
1090
30.
0021
4.68
698
0.11
730.
3118
30.
0081
0.07
239
0.00
1817
8336
1765
2017
5040
1413
3498
0.28
1244
0.00
0015
0.00
0887
0.02
3501
0.28
1203
-0.9
30.
532.
793.
04W
AN
G-7
0.12
530
0.00
266.
4167
30.
1634
0.37
148
0.00
960.
1072
10.
0027
2033
3820
3522
2036
4620
5850
100
0.28
1416
0.00
0013
0.00
0542
0.01
4335
0.28
1398
-8.9
40.
462.
543.
04W
AN
G-1
00.
1135
00.
0024
5.23
033
0.14
070.
3342
10.
0090
0.09
465
0.00
2418
5640
1858
2218
5944
1828
4410
00.
2813
980.
0000
140.
0006
340.
0173
160.
2813
74-4
.10
0.49
2.57
2.93
WA
NG
-14
0.11
483
0.00
235.
1233
90.
1342
0.32
360
0.00
870.
0885
70.
0022
1877
3618
4022
1807
4217
1540
960.
2815
520.
0000
140.
0005
330.
0148
630.
2815
33-2
.47
0.49
2.35
2.69
WA
NG
-15
0.12
421
0.00
256.
2532
80.
1621
0.36
517
0.00
970.
1033
80.
0027
2018
3820
1222
2007
4619
8848
990.
2815
700.
0000
170.
0009
620.
0303
150.
2815
36-1
.90
0.60
2.35
2.67
WA
NG
-16
0.11
877
0.00
255.
6697
80.
1483
0.34
623
0.00
920.
0955
50.
0025
1938
3819
2722
1917
4418
4446
990.
2814
320.
0000
180.
0007
560.
0216
780.
2814
03-3
.40
0.63
2.53
2.87
WA
NG
-17
0.12
309
0.00
266.
0075
60.
1454
0.35
409
0.00
860.
1066
00.
0026
2001
3819
7722
1954
4020
4746
980.
2813
860.
0000
250.
0004
620.
0138
840.
2813
69-6
.43
0.88
2.57
3.00
WA
NG
-18
0.12
606
0.00
256.
3232
60.
1466
0.36
386
0.00
860.
1099
20.
0024
2044
3620
2220
2000
4021
0844
980.
2814
640.
0000
170.
0006
590.
0196
290.
2814
39-2
.51
0.60
2.48
2.80
WA
NG
-19
0.12
469
0.00
256.
2545
50.
1425
0.36
380
0.00
850.
1040
90.
0023
2024
3620
1220
2000
4020
0142
990.
2814
060.
0000
130.
0004
600.
0137
330.
2813
88-3
.33
0.46
2.54
2.89
WA
NG
-20
0.12
415
0.00
275.
9993
80.
1547
0.35
055
0.00
890.
0925
90.
0025
2017
4019
7622
1937
4217
9046
960.
2814
270.
0000
130.
0006
080.
0178
710.
2814
04-3
.24
0.46
2.53
2.87
WA
NG
-22
0.12
435
0.00
296.
2018
70.
1689
0.36
181
0.00
950.
1047
90.
0032
2020
4220
0524
1991
4420
1458
990.
2814
040.
0000
190.
0005
840.
0176
750.
2813
82-4
.18
0.67
2.56
2.92
WA
NG
-24
0.10
700
0.00
224.
4613
60.
1117
0.30
245
0.00
770.
0455
30.
0011
1749
3817
2420
1703
3890
022
970.
2813
970.
0000
210.
0006
320.
0190
490.
2813
73-4
.43
0.74
2.57
2.94
WA
NG
-27
0.15
909
0.00
3210
.015
290.
2323
0.45
659
0.01
090.
1334
40.
0028
2446
3424
3622
2424
4825
3250
990.
2813
500.
0000
240.
0006
430.
0196
810.
2813
25-5
.64
0.84
2.63
3.03
WA
NG
-28
0.10
851
0.00
224.
7435
10.
1149
0.31
711
0.00
790.
0805
30.
0020
1775
3817
7520
1776
3815
6538
100
0.28
1244
0.00
0012
0.00
0653
0.02
0608
0.28
1214
-0.3
20.
422.
783.
00W
AN
G-3
00.
1241
40.
0025
6.28
558
0.14
590.
3672
40.
0088
0.10
912
0.00
2420
1736
2016
2020
1642
2093
4410
00.
2813
940.
0000
210.
0008
650.
0280
110.
2813
65-1
0.29
0.74
2.59
3.12
WA
NG
-32
0.11
323
0.00
234.
8265
30.
1219
0.30
930
0.00
810.
0244
00.
0006
1852
3817
9022
1737
4048
712
940.
2813
790.
0000
170.
0006
960.
0212
070.
2813
52-5
.22
0.60
2.60
2.99
-46-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
WA
NG
-33C
0.12
444
0.00
266.
3602
90.
1552
0.37
100
0.00
910.
1133
90.
0027
2021
3820
2722
2034
4221
7150
101
0.28
1626
0.00
0016
0.00
0856
0.02
8276
0.28
1596
-0.3
30.
562.
272.
55W
AN
G-3
3R0.
1244
90.
0028
6.40
488
0.16
510.
3733
80.
0093
0.10
632
0.00
3120
2242
2033
2220
4544
2042
5810
1W
AN
G-3
40.
1155
50.
0023
5.26
598
0.11
810.
3305
40.
0077
0.05
091
0.00
1218
8836
1863
2018
4138
1004
2498
0.28
1404
0.00
0012
0.00
0979
0.02
9910
0.28
1366
-4.6
30.
422.
582.
95W
AN
G-3
90.
1256
90.
0026
6.48
063
0.15
700.
3741
90.
0092
0.11
491
0.00
2720
3938
2043
2220
4944
2199
5010
00.
2821
430.
0000
100.
0005
500.
0156
820.
2821
312.
680.
351.
551.
81W
AN
G-4
00.
1264
40.
0027
6.46
950
0.16
070.
3712
70.
0092
0.11
363
0.00
2920
4938
2042
2220
3544
2175
5499
0.28
1415
0.00
0024
0.00
0732
0.02
2546
0.28
1387
-3.5
00.
842.
552.
89W
AN
G-4
10.
1257
90.
0025
6.46
571
0.15
060.
3727
70.
0089
0.10
826
0.00
2520
4036
2041
2020
4242
2078
4610
00.
2814
520.
0000
280.
0005
040.
0144
900.
2814
32-1
.65
0.98
2.49
2.78
WA
NG
-44
0.15
108
0.00
308.
9677
80.
2170
0.43
072
0.01
080.
1308
30.
0031
2358
3423
3522
2309
4824
8556
980.
2813
160.
0000
150.
0008
760.
0261
680.
2812
82-7
.19
0.53
2.69
3.13
WA
NG
-46
0.12
504
0.00
256.
2908
00.
1544
0.36
497
0.00
920.
1064
20.
0024
2029
3620
1722
2006
4420
4444
990.
2810
370.
0000
170.
0009
060.
0260
850.
2809
96-1
0.07
0.60
3.07
3.56
WA
NG
-48
0.12
517
0.00
256.
1791
60.
1500
0.35
810
0.00
890.
1017
00.
0024
2031
3620
0222
1973
4219
5844
97W
AN
G-4
90.
1585
80.
0031
9.84
738
0.22
780.
4504
60.
0109
0.12
455
0.00
2624
4134
2421
2223
9748
2373
4898
0.28
1430
0.00
0019
0.00
0882
0.02
5194
0.28
1396
-3.4
00.
672.
542.
88W
AN
G-5
30.
1230
70.
0026
6.32
028
0.15
600.
3725
00.
0093
0.10
931
0.00
2720
0138
2021
2220
4144
2097
4810
2W
AN
G-5
50.
1237
80.
0025
6.39
469
0.15
330.
3747
60.
0092
0.10
855
0.00
2520
1136
2032
2220
5244
2083
4410
2W
AN
G-5
60.
1263
80.
0025
6.28
160
0.14
150.
3606
60.
0084
0.07
500
0.00
1520
4836
2016
2019
8540
1462
2897
WA
NG
-60
0.12
368
0.00
266.
3120
80.
1499
0.37
022
0.00
890.
1058
90.
0025
2010
3820
2020
2030
4220
3446
101
WA
NG
-62
0.11
337
0.00
225.
2645
20.
1228
0.33
688
0.00
810.
0869
20.
0019
1854
3618
6320
1872
4016
8536
101
0.28
1249
0.00
0016
0.00
0659
0.01
8993
0.28
1218
-0.2
60.
562.
773.
00W
AN
G-6
30.
1237
70.
0025
5.95
549
0.13
990.
3491
10.
0084
0.04
720
0.00
1020
1136
1969
2019
3040
932
2096
0.28
1522
0.00
0016
0.00
0652
0.02
0628
0.28
1499
-3.7
30.
562.
402.
76W
AN
G-7
00.
1245
40.
0026
6.35
443
0.15
800.
3701
20.
0093
0.11
051
0.00
2620
2238
2026
2220
3044
2119
4810
0W
AN
G-7
10.
1256
70.
0027
6.48
580
0.16
960.
3744
00.
0097
0.11
041
0.00
2820
3838
2044
2420
5046
2117
5210
1W
AN
G-7
20.
1264
90.
0026
6.49
045
0.15
850.
3724
00.
0091
0.11
054
0.00
2520
5038
2045
2220
4142
2119
4610
0W
AN
G-7
40.
1256
50.
0026
6.44
563
0.16
140.
3721
90.
0094
0.10
910
0.00
2620
3838
2039
2220
4044
2093
4610
0W
AN
G-8
20.
1258
30.
0025
6.17
696
0.14
970.
3562
20.
0088
0.06
552
0.00
1420
4136
2001
2219
6442
1283
2696
WA
NG
-85
0.12
572
0.00
256.
5908
70.
1589
0.38
040
0.00
940.
1156
70.
0025
2039
3620
5822
2078
4422
1244
102
WA
NG
-88
0.12
499
0.00
256.
3908
50.
1541
0.37
105
0.00
910.
1113
00.
0024
2029
3620
3122
2034
4221
3344
100
WA
NG
-89
0.12
433
0.00
256.
4414
10.
1563
0.37
595
0.00
920.
1122
70.
0025
2019
3820
3822
2057
4421
5146
102
WA
NG
-92
0.11
345
0.00
225.
2216
80.
1292
0.33
403
0.00
850.
0884
80.
0021
1855
3618
5622
1858
4217
1438
100
0.28
1392
0.00
0013
0.00
0776
0.02
2557
0.28
1362
-5.0
00.
462.
582.
97W
AN
G-9
60.
1570
10.
0031
9.29
150
0.21
040.
4294
10.
0101
0.12
992
0.00
2724
2433
2367
2123
0345
2469
4895
0.28
1608
0.00
0018
0.00
1284
0.03
8954
0.28
1563
-1.4
40.
632.
322.
62W
AN
G-9
70.
1241
40.
0025
6.26
427
0.15
190.
3659
00.
0091
0.09
556
0.00
2220
1736
2013
2220
1042
1845
4210
0W
AN
G-9
80.
1129
90.
0022
4.94
003
0.11
810.
3173
20.
0079
0.10
611
0.00
2018
4836
1809
2017
7738
2038
3896
0.28
1280
0.00
0022
0.00
1103
0.03
2323
0.28
1229
-0.2
80.
772.
762.
99W
AN
G-9
90.
1650
20.
0032
10.7
9239
0.23
560.
4743
30.
0109
0.12
554
0.00
2425
0832
2505
2025
0348
2390
4210
00.
2816
500.
0000
230.
0009
270.
0261
270.
2816
170.
340.
812.
242.
50W
AN
G-1
020.
1142
20.
0022
5.26
473
0.11
810.
3342
60.
0079
0.09
758
0.00
1818
6836
1863
2018
5938
1882
3410
00.
2811
990.
0000
140.
0014
950.
0423
940.
2811
27-1
.95
0.49
2.90
3.16
WA
NG
-103
0.12
419
0.00
246.
2266
20.
1414
0.36
362
0.00
860.
0785
10.
0014
2017
3620
0820
1999
4015
2826
99W
AN
G-1
040.
1238
60.
0024
6.24
943
0.13
780.
3660
20.
0084
0.11
262
0.00
2020
1336
2011
2020
1140
2157
3610
0W
AN
G-1
060.
1235
00.
0024
6.17
065
0.13
850.
3624
90.
0085
0.10
185
0.00
1920
0736
2000
2019
9440
1960
3499
0.28
1542
0.00
0020
0.00
0861
0.02
6788
0.28
1511
-2.9
70.
702.
392.
73P
ineC
reek
1-8
0.18
456
0.00
3813
.051
880.
2485
0.51
344
0.00
970.
1334
40.
0026
2694
3426
8318
2671
4225
3246
990.
2812
670.
0000
190.
0005
690.
0197
570.
2812
49-1
6.00
0.67
2.74
3.42
Pin
eCre
ek1-
20C
0.10
487
0.00
454.
1418
40.
1659
0.28
646
0.00
610.
0854
00.
0028
1712
8016
6332
1624
3016
5652
950.
2813
100.
0000
090.
0007
170.
0264
400.
2812
85-1
1.33
0.31
2.69
3.25
Pin
eCre
ek1-
20R
0.09
872
0.00
303.
8514
10.
1124
0.28
294
0.00
590.
0708
80.
0016
1600
5816
0424
1606
3013
8430
100
Pin
eCre
ek1-
220.
2434
30.
0049
21.1
2314
0.39
410.
6294
30.
0118
0.04
246
0.00
1031
4332
3144
1831
4746
840
2010
00.
2818
950.
0000
080.
0006
720.
0208
740.
2818
736.
330.
281.
892.
01P
ineC
reek
1-23
0.11
659
0.00
245.
3376
00.
0992
0.33
208
0.00
610.
0830
80.
0015
1905
3818
7516
1848
3016
1328
970.
2807
300.
0000
080.
0002
810.
0080
970.
2807
13-1
.95
0.28
3.43
3.64
Pin
eCre
ek1-
240.
2424
60.
0061
18.5
7639
0.48
080.
5560
40.
0135
0.06
549
0.00
2131
3640
3020
2428
5056
1282
4091
0.28
1575
0.00
0010
0.00
0488
0.01
6389
0.28
1557
-0.4
90.
332.
322.
60P
ineC
reek
1-27
0.16
181
0.00
3410
.471
590.
2301
0.46
933
0.01
010.
1019
70.
0019
2475
3624
7720
2481
4419
6336
100
0.28
0832
0.00
0008
0.00
1083
0.03
9430
0.28
0766
0.25
0.29
3.37
3.51
Pin
eCre
ek1-
300.
1647
70.
0034
10.9
4995
0.19
150.
4820
90.
0082
0.12
312
0.00
2025
0536
2519
1625
3636
2347
3610
10.
2808
210.
0000
080.
0007
080.
0234
700.
2807
88-1
4.80
0.29
3.35
3.94
Pin
eCre
ek1-
320.
1645
90.
0034
10.2
6758
0.18
110.
4524
80.
0078
0.10
381
0.00
1825
0336
2459
1624
0634
1996
3296
0.28
0763
0.00
0008
0.00
1311
0.05
3040
0.28
0681
-0.6
70.
293.
483.
64P
ineC
reek
1-36
0.25
746
0.00
5121
.414
670.
3760
0.60
334
0.01
080.
1443
10.
0025
3231
3231
5818
3043
4427
2544
940.
2812
860.
0000
100.
0008
100.
0308
250.
2812
62-1
8.65
0.35
2.73
3.48
Pin
eCre
ek1-
470.
2032
80.
0044
15.2
4712
0.27
400.
5442
40.
0093
0.14
641
0.00
3228
5336
2831
1828
0138
2762
5698
0.28
0756
0.00
0010
0.00
1057
0.03
6385
0.28
0690
-0.7
00.
353.
473.
63P
ineC
reek
1-48
0.24
240
0.00
4820
.990
470.
3601
0.62
814
0.01
100.
0905
10.
0015
3136
3231
3816
3142
4417
5128
100
0.28
1087
0.00
0010
0.00
1212
0.03
6565
0.28
1021
2.25
0.33
3.03
3.15
Pin
eCre
ek1-
490.
1103
20.
0031
4.62
832
0.11
440.
3043
30.
0056
0.08
696
0.00
1918
0552
1754
2017
1328
1685
3695
0.28
0749
0.00
0009
0.00
0845
0.02
6154
0.28
0698
-2.6
40.
313.
463.
68P
ineC
reek
1-52
0.10
215
0.00
244.
0730
80.
0826
0.28
925
0.00
500.
0837
70.
0019
1664
4416
4916
1638
2616
2636
980.
2815
340.
0000
120.
0005
980.
0169
610.
2815
14-4
.33
0.42
2.38
2.77
Pin
eCre
ek1-
570.
1635
20.
0037
10.5
6854
0.21
530.
4684
50.
0086
0.12
230
0.00
2224
9240
2486
1824
7738
2332
4099
0.28
2344
0.00
0010
0.00
0767
0.02
3949
0.28
2336
-3.2
70.
331.
281.
73P
ineC
reek
1-70
0.18
426
0.00
3912
.782
460.
2767
0.50
402
0.01
090.
0908
00.
0023
2692
3626
6420
2631
4617
5742
980.
2813
770.
0000
110.
0012
100.
0399
660.
2813
54-2
7.99
0.39
2.63
3.62
Pin
eCre
ek1-
73C
0.16
358
0.00
3510
.366
490.
2259
0.46
075
0.00
990.
1144
50.
0027
2493
3624
6820
2443
4421
9048
980.
2811
440.
0000
130.
0026
850.
0959
160.
2810
06-2
.02
0.46
3.07
3.30
Pin
eCre
ek1-
73R
0.16
785
0.00
3411
.359
280.
2143
0.49
045
0.00
920.
1220
50.
0024
2536
3625
5318
2573
4023
2844
101
Pin
eCre
ek1-
830.
2237
80.
0045
18.0
0613
0.29
740.
5833
80.
0098
0.14
256
0.00
2430
0832
2990
1629
6340
2694
4299
0.28
1277
0.00
0010
0.00
0762
0.02
1010
0.28
1241
1.73
0.35
2.74
2.91
Pin
eCre
ek1-
920.
1044
70.
0023
4.36
484
0.08
710.
3030
60.
0057
0.08
951
0.00
1817
0540
1706
1617
0628
1733
3210
00.
2819
360.
0000
080.
0016
740.
0509
930.
2818
99-4
.83
0.29
1.88
2.31
Pin
eCre
ek1-
960.
2312
60.
0049
18.9
0939
0.33
270.
5930
90.
0103
0.13
711
0.00
2630
6134
3037
1630
0242
2597
4698
0.28
0829
0.00
0009
0.00
1382
0.04
9532
0.28
0751
-5.0
80.
313.
403.
70
-47-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
Pin
eCre
ek1-
990.
1071
00.
0024
4.62
968
0.08
630.
3135
20.
0052
0.08
805
0.00
1817
5142
1755
1617
5826
1706
3410
00.
2807
030.
0000
120.
0006
980.
0197
030.
2806
62-5
.68
0.42
3.51
3.82
Pin
eCre
ek1-
103C
0.10
108
0.00
503.
7630
60.
1671
0.27
000
0.00
560.
0787
60.
0017
1644
9415
8536
1541
2815
3232
94P
ineC
reek
1-10
3R0.
0964
50.
0031
3.71
912
0.11
780.
2796
50.
0063
0.07
608
0.00
2315
5762
1575
2615
9032
1482
4410
2P
ineC
reek
1-11
10.
2575
60.
0052
23.1
2623
0.42
370.
6507
70.
0120
0.14
929
0.00
2832
3232
3232
1832
3146
2812
4810
00.
2821
240.
0000
100.
0004
820.
0157
270.
2821
141.
160.
351.
571.
87P
ineC
reek
1-11
20.
2556
70.
0052
22.8
2356
0.38
960.
6474
80.
0111
0.16
493
0.00
2932
2034
3219
1632
1844
3086
5010
00.
2807
310.
0000
090.
0006
700.
0211
690.
2806
89-0
.71
0.32
3.47
3.63
Pin
eCre
ek1-
114C
0.10
078
0.00
223.
9780
30.
0784
0.28
586
0.00
530.
0824
30.
0016
1639
4016
3016
1621
2616
0130
990.
2821
070.
0000
080.
0006
820.
0225
900.
2820
8611
.09
0.28
1.60
1.61
Pin
eCre
ek1-
117
0.25
058
0.00
5021
.925
970.
3763
0.63
450
0.01
100.
1646
00.
0030
3188
3231
8016
3167
4430
8052
990.
2816
880.
0000
070.
0005
970.
0199
090.
2816
69-2
.56
0.25
2.17
2.52
Pin
eCre
ek1-
118
0.16
339
0.00
3510
.555
340.
1967
0.46
827
0.00
840.
1271
80.
0025
2491
3624
8518
2476
3824
2044
990.
2808
250.
0000
160.
0007
010.
0195
230.
2807
821.
560.
563.
343.
45P
ineC
reek
1-11
90.
1621
70.
0034
10.2
8406
0.18
420.
4598
50.
0080
0.12
446
0.00
2224
7836
2461
1624
3936
2371
4098
0.28
0876
0.00
0009
0.00
0378
0.01
2153
0.28
0858
-11.
920.
313.
253.
77P
ineC
reek
1-12
10.
0965
20.
0026
3.64
537
0.09
060.
2737
30.
0052
0.07
677
0.00
2015
5852
1559
2015
6026
1495
3810
00.
2809
150.
0000
100.
0006
970.
0214
400.
2808
82-1
1.37
0.34
3.22
3.73
LT1-
20.
2166
00.
0044
17.2
9483
0.30
920.
5792
50.
0103
0.14
285
0.00
2629
5634
2951
1829
4642
2699
4610
00.
2821
490.
0000
090.
0004
600.
0131
510.
2821
392.
660.
321.
531.
80LT
1-5
0.10
735
0.00
224.
2483
80.
0769
0.28
717
0.00
500.
0414
50.
0007
1755
4016
8314
1627
2682
114
930.
2821
100.
0000
110.
0004
350.
0141
210.
2821
010.
890.
391.
591.
90LT
1-8C
0.10
663
0.00
244.
6229
30.
0938
0.31
448
0.00
590.
0553
80.
0010
1743
4217
5316
1763
2810
8920
101
0.28
1518
0.00
0006
0.00
0654
0.02
1499
0.28
1496
-6.0
80.
222.
412.
84LT
1-8R
0.10
394
0.00
224.
2525
00.
0778
0.29
682
0.00
520.
0584
70.
0012
1696
4016
8416
1676
2611
4924
99LT
1-12
0.10
397
0.00
214.
2947
90.
0762
0.29
976
0.00
530.
0710
10.
0013
1696
3816
9214
1690
2613
8724
100
0.28
2102
0.00
0008
0.00
0570
0.01
8568
0.28
2089
2.54
0.29
1.60
1.86
LT1-
150.
1122
40.
0027
4.95
184
0.10
260.
3201
90.
0058
0.08
821
0.00
2518
3644
1811
1817
9128
1709
4698
0.28
2011
0.00
0009
0.00
0400
0.01
0694
0.28
2003
-2.3
20.
321.
722.
11LT
1-17
0.10
713
0.00
264.
3918
00.
0960
0.29
749
0.00
540.
0331
50.
0008
1751
4617
1118
1679
2865
916
960.
2815
880.
0000
070.
0015
720.
0608
920.
2815
33-2
.92
0.25
2.37
2.70
LT1-
350.
1029
30.
0023
3.94
820
0.08
280.
2782
10.
0054
0.07
610
0.00
1416
7842
1624
1615
8228
1482
2694
0.28
2115
0.00
0010
0.00
1536
0.05
2845
0.28
2072
8.02
0.35
1.63
1.72
LT1-
390.
1414
30.
0030
8.00
762
0.15
020.
4106
40.
0074
0.11
105
0.00
2122
4538
2232
1622
1834
2128
3899
0.28
1648
0.00
0014
0.00
1027
0.02
9733
0.28
1615
-3.5
90.
492.
252.
62LT
1-41
0.11
120
0.00
234.
7803
70.
1010
0.31
182
0.00
650.
0676
90.
0013
1819
3817
8118
1750
3213
2424
960.
2812
810.
0000
120.
0005
100.
0158
920.
2812
59-3
.31
0.42
2.72
3.04
LT1-
420.
1048
10.
0025
3.95
648
0.08
770.
2738
00.
0052
0.07
681
0.00
1517
1146
1625
1815
6026
1496
2891
0.28
1569
0.00
0008
0.00
0659
0.02
4771
0.28
1546
-2.8
40.
292.
342.
68LT
1-48
0.10
413
0.00
224.
3734
00.
0825
0.30
462
0.00
550.
0701
60.
0013
1699
4017
0716
1714
2813
7124
101
0.28
2094
0.00
0009
0.00
0469
0.01
4421
0.28
2085
-0.5
80.
321.
611.
96LT
1-54
0.10
468
0.00
244.
1476
90.
0834
0.28
734
0.00
510.
0756
10.
0017
1709
4416
6416
1628
2614
7332
950.
2815
550.
0000
090.
0004
100.
0117
830.
2815
376.
850.
332.
342.
40LT
1-60
0.10
331
0.00
244.
2224
10.
0857
0.29
657
0.00
530.
0783
90.
0014
1684
4416
7816
1674
2615
2526
990.
2816
100.
0000
110.
0008
990.
0322
090.
2815
81-4
.11
0.39
2.30
2.68
LT1-
620.
1038
70.
0023
3.95
287
0.07
830.
2759
50.
0051
0.01
711
0.00
0316
9442
1625
1615
7126
343
693
0.28
1681
0.00
0007
0.00
0746
0.02
2258
0.28
1657
-1.9
70.
252.
192.
52LT
1-65
0.10
329
0.00
223.
8562
40.
0744
0.27
026
0.00
500.
0657
50.
0012
1684
4016
0516
1542
2612
8722
920.
2816
370.
0000
070.
0009
940.
0301
680.
2816
05-3
.59
0.26
2.26
2.63
LT1-
660.
1031
40.
0021
4.10
743
0.07
570.
2884
50.
0052
0.08
066
0.00
1516
8138
1656
1616
3426
1568
2897
0.28
1518
0.00
0010
0.00
0594
0.01
7817
0.28
1499
-7.5
90.
352.
402.
88LT
1-76
0.10
164
0.00
223.
9734
10.
0769
0.28
366
0.00
510.
0635
40.
0013
1654
4216
2916
1610
2612
4526
970.
2823
560.
0000
100.
0004
830.
0151
350.
2823
500.
210.
331.
251.
61LT
1-79
0.10
717
0.00
244.
4982
50.
0890
0.30
444
0.00
550.
0461
30.
0010
1752
4217
3116
1713
2891
220
98LT
1-90
C0.
1038
10.
0022
4.37
305
0.08
660.
3052
30.
0057
0.08
276
0.00
1516
9340
1707
1617
1728
1607
2810
10.
2821
160.
0000
140.
0006
490.
0187
760.
2821
022.
400.
491.
591.
85LT
1-93
R0.
1109
60.
0026
4.58
517
0.09
220.
2996
30.
0053
0.07
969
0.00
1518
1544
1747
1616
8926
1550
2893
0.28
2138
0.00
0008
0.00
0643
0.01
8934
0.28
2124
3.23
0.27
1.56
1.80
LT1-
104
0.11
597
0.00
275.
1198
00.
1179
0.32
384
0.00
670.
0552
80.
0012
1895
4418
3920
1808
3210
8822
950.
2822
230.
0000
090.
0006
950.
0221
500.
2822
093.
480.
321.
441.
69M
YA
LL-1
0.09
873
0.00
473.
8772
30.
1826
0.28
474
0.00
740.
0843
80.
0055
1600
9216
0938
1615
3616
3710
210
10.
2815
680.
0000
080.
0007
090.
0222
400.
2815
43-1
.25
0.28
2.34
2.64
MY
ALL
-80.
1026
10.
0034
4.08
544
0.12
620.
2888
80.
0059
0.08
540
0.00
2816
7262
1651
2616
3630
1656
5298
0.28
2229
0.00
0009
0.00
0731
0.02
2031
0.28
2213
6.10
0.32
1.43
1.61
MY
ALL
-90.
2444
90.
0051
21.0
7219
0.39
940.
6254
30.
0116
0.17
528
0.00
4431
4934
3142
1831
3146
3264
7699
0.28
1825
0.00
0010
0.00
0569
0.01
5195
0.28
1807
3.07
0.34
1.98
2.19
MY
ALL
-10
0.10
323
0.00
263.
9557
70.
0922
0.27
802
0.00
540.
0834
10.
0024
1683
4616
2518
1581
2816
1944
940.
2807
910.
0000
110.
0005
360.
0145
070.
2807
59-0
.19
0.39
3.37
3.54
MY
ALL
-28
0.10
308
0.00
224.
1445
50.
0889
0.29
157
0.00
590.
0900
50.
0018
1680
4216
6318
1649
3017
4334
980.
2821
820.
0000
090.
0005
180.
0141
880.
2821
704.
890.
331.
491.
69M
YA
LL-3
30.
0995
20.
0022
3.82
268
0.09
320.
2786
40.
0064
0.03
284
0.00
1116
1542
1598
2015
8532
653
2098
0.28
1834
0.00
0009
0.00
0359
0.01
0651
0.28
1826
-6.5
90.
311.
962.
45M
YA
LL-3
40.
1423
80.
0029
8.18
590
0.15
390.
4169
30.
0077
0.12
501
0.00
2422
5636
2252
1822
4736
2381
4410
00.
2819
690.
0000
110.
0030
870.
1016
140.
2818
754.
180.
391.
912.
08M
YA
LL-4
00.
1059
40.
0026
4.47
473
0.10
390.
3063
70.
0061
0.09
449
0.00
2417
3146
1726
2017
2330
1825
4410
00.
2824
440.
0000
110.
0025
150.
0757
530.
2824
016.
760.
391.
191.
36M
YA
LL-4
10.
1008
20.
0023
4.00
834
0.08
780.
2883
90.
0058
0.09
025
0.00
1916
3942
1636
1816
3328
1746
3610
00.
2817
300.
0000
120.
0005
300.
0143
920.
2817
131.
060.
422.
112.
37M
YA
LL-4
60.
1011
80.
0035
4.03
511
0.14
160.
2894
70.
0072
0.08
755
0.00
3016
4666
1641
2816
3936
1696
5610
00.
2822
590.
0000
080.
0006
910.
0195
410.
2822
438.
820.
281.
391.
49M
YA
LL-4
70.
1013
50.
0021
3.91
005
0.07
900.
2798
20.
0055
0.06
813
0.00
1316
4940
1616
1615
9028
1332
2496
0.28
1896
0.00
0012
0.00
0511
0.01
4209
0.28
1880
5.08
0.42
1.88
2.04
MY
ALL
-48
0.10
893
0.00
244.
8249
40.
1005
0.32
127
0.00
630.
0937
20.
0020
1782
4217
8918
1796
3018
1136
101
0.28
1915
0.00
0008
0.00
1222
0.03
2962
0.28
1877
5.03
0.27
1.89
2.05
MY
ALL
-58
0.10
234
0.00
233.
8916
30.
0820
0.27
575
0.00
540.
0806
80.
0017
1667
4216
1218
1570
2815
6832
940.
2824
090.
0000
080.
0009
020.
0288
020.
2823
981.
530.
281.
191.
51M
YA
LL-5
90.
1064
60.
0022
4.51
102
0.08
680.
3072
10.
0057
0.09
381
0.00
1917
4040
1733
1617
2728
1812
3499
0.28
1634
0.00
0008
0.00
0497
0.01
4443
0.28
1618
-3.7
40.
282.
242.
62M
YA
LL-6
00.
0961
30.
0024
3.50
511
0.08
340.
2644
40.
0052
0.07
823
0.00
2015
5048
1528
1815
1326
1522
3698
0.28
1488
0.00
0011
0.00
0447
0.01
3636
0.28
1473
-7.2
30.
392.
432.
90M
YA
LL-6
70.
0981
60.
0021
3.79
674
0.08
260.
2803
80.
0059
0.07
653
0.00
1815
8940
1592
1815
9330
1491
3410
00.
2821
530.
0000
100.
0008
760.
0275
470.
2821
342.
310.
351.
551.
81M
YA
LL-7
10.
0947
60.
0021
3.49
569
0.07
230.
2674
00.
0050
0.07
585
0.00
1815
2344
1526
1615
2826
1478
3410
00.
2819
300.
0000
100.
0002
710.
0096
300.
2819
24-3
.59
0.34
1.82
2.24
MY
ALL
-73
0.10
064
0.00
213.
7021
10.
0736
0.26
667
0.00
520.
0598
20.
0013
1636
4015
7216
1524
2611
7424
930.
2820
980.
0000
130.
0010
940.
0308
080.
2820
668.
910.
461.
631.
70M
YA
LL-7
40.
1989
00.
0039
14.7
7674
0.28
260.
5388
40.
0105
0.13
374
0.00
2428
1732
2801
1827
7944
2537
4299
0.28
1893
0.00
0009
0.00
1509
0.04
8432
0.28
1846
3.65
0.32
1.94
2.13
MY
ALL
-79
0.17
925
0.00
3912
.557
670.
2944
0.50
815
0.01
150.
1320
80.
0029
2646
3626
4722
2649
5025
0752
100
0.28
0789
0.00
0009
0.00
0586
0.01
4962
0.28
0757
-7.9
60.
323.
383.
78M
YA
LL-9
10.
1018
30.
0063
4.06
729
0.24
520.
2897
30.
0068
0.07
797
0.00
2216
5811
616
4850
1640
3415
1842
990.
2809
980.
0000
080.
0005
000.
0146
440.
2809
73-4
.26
0.26
3.09
3.41
MY
ALL
-101
0.10
089
0.00
233.
9963
20.
0955
0.28
734
0.00
630.
0421
00.
0011
1641
4416
3320
1628
3283
420
990.
2820
430.
0000
100.
0061
870.
2502
530.
2818
326.
770.
351.
972.
05
-48-
Chapter 2 Supplementary MaterialA
naly
sis
Isot
ope
Rat
ios
Age
s (M
a)Is
otop
e R
atio
sS
cher
er e
t al.
2001
dec
ay c
onst
ant
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
%co
n17
6 Hf/17
7 Hf
1 S
E17
6 Lu/17
7 Hf
176 Yb
/177 H
fH
f iH
f1
SE
T DM
(Ga)
T DM
Cru
stal
(Ga)
MY
ALL
-108
0.10
738
0.00
234.
7733
10.
1009
0.32
232
0.00
660.
0859
20.
0019
1755
4017
8018
1801
3216
6636
103
0.28
1627
0.00
0008
0.00
0673
0.01
9137
0.28
1606
-4.7
60.
282.
262.
67M
YA
LL-1
140.
1150
30.
0026
5.42
034
0.11
690.
3416
80.
0067
0.09
462
0.00
2118
8042
1888
1818
9532
1827
4010
10.
2815
440.
0000
090.
0006
730.
0201
930.
2815
22-5
.17
0.30
2.37
2.78
MY
ALL
-115
0.09
753
0.00
213.
6598
20.
0856
0.27
212
0.00
600.
0433
10.
0009
1577
4215
6318
1552
3085
716
980.
2815
370.
0000
120.
0011
050.
0297
240.
2814
98-3
.19
0.42
2.41
2.75
Eas
tBar
ton-
1C0.
1619
70.
0036
10.6
1595
0.22
620.
4755
20.
0096
0.11
999
0.00
2624
7638
2490
2025
0842
2290
4610
10.
2824
900.
0000
100.
0027
210.
1143
200.
2824
563.
360.
351.
131.
39E
astB
arto
n-1R
0.15
819
0.00
3310
.089
340.
2103
0.46
263
0.00
960.
1285
10.
0027
2436
3624
4320
2451
4224
4448
101
0.28
1050
0.00
0005
0.00
0670
0.02
2381
0.28
1018
-6.5
70.
163.
043.
43E
astB
arto
n-13
0.10
506
0.00
254.
3552
90.
1028
0.30
084
0.00
630.
0891
30.
0019
1715
4417
0420
1695
3217
2634
990.
2822
540.
0000
120.
0007
170.
0232
910.
2822
403.
440.
421.
401.
65E
astB
arto
n-14
0.17
043
0.00
6811
.052
620.
3547
0.47
035
0.01
120.
1302
50.
0031
2562
6825
2830
2485
5024
7556
970.
2815
520.
0000
100.
0011
030.
0316
500.
2815
16-6
.28
0.35
2.39
2.82
Eas
tBar
ton-
170.
1082
50.
0023
4.66
130
0.09
960.
3125
70.
0065
0.04
145
0.00
0917
7040
1760
1817
5332
821
1899
0.28
1076
0.00
0009
0.00
0221
0.00
6287
0.28
1065
-2.9
20.
332.
973.
26E
astB
arto
n-28
0.10
193
0.00
774.
0591
30.
2893
0.28
881
0.00
750.
0841
70.
0020
1660
144
1646
5816
3638
1633
3899
0.28
1970
0.00
0013
0.00
0566
0.01
5799
0.28
1955
2.00
0.46
1.78
2.04
Eas
tBar
ton-
330.
1337
20.
0028
7.26
939
0.14
130.
3943
60.
0075
0.11
636
0.00
2621
4738
2145
1821
4334
2225
4610
00.
2820
970.
0000
100.
0005
550.
0157
030.
2820
852.
000.
341.
611.
88E
astB
arto
n-35
0.09
981
0.00
233.
9600
60.
0980
0.28
745
0.00
650.
0823
80.
0020
1621
4416
2620
1629
3216
0038
100
0.28
2264
0.00
0010
0.00
0449
0.01
3159
0.28
2255
5.22
0.35
1.38
1.58
Eas
tBar
ton-
390.
1621
70.
0036
10.4
3732
0.25
470.
4663
60.
0108
0.12
361
0.00
3124
7838
2474
2224
6848
2356
5610
00.
2821
300.
0000
070.
0005
250.
0149
140.
2821
182.
840.
251.
561.
82E
astB
arto
n-44
0.11
162
0.00
284.
9719
40.
1166
0.32
326
0.00
630.
1018
40.
0027
1826
4618
1520
1806
3019
6050
990.
2820
570.
0000
120.
0006
040.
0175
690.
2820
423.
080.
421.
671.
91E
astB
arto
n-53
0.10
723
0.00
294.
6055
30.
1209
0.31
150
0.00
660.
0929
80.
0023
1753
5017
5022
1748
3217
9744
100
0.28
2146
0.00
0013
0.00
0620
0.01
7611
0.28
2132
3.09
0.46
1.54
1.79
Eas
tBar
ton-
550.
1596
60.
0037
10.2
6670
0.21
670.
4665
00.
0090
0.13
583
0.00
3224
5240
2459
2024
6840
2574
5810
10.
2824
010.
0000
190.
0001
730.
0050
070.
2823
989.
640.
671.
181.
28E
astB
arto
n-71
0.20
448
0.00
4016
.660
250.
3262
0.58
965
0.01
190.
1570
30.
0030
2862
3229
1518
2988
4829
4852
104
Eas
tBar
ton-
720.
1081
90.
0027
4.62
783
0.12
550.
3102
20.
0076
0.05
435
0.00
1417
6946
1754
2217
4238
1070
2898
0.28
2214
0.00
0008
0.00
0596
0.01
6630
0.28
2201
4.92
0.29
1.45
1.66
Eas
tBar
ton-
750.
1563
10.
0034
9.93
839
0.20
440.
4609
60.
0091
0.13
064
0.00
3524
1638
2429
1824
4440
2482
6210
10.
2815
900.
0000
080.
0006
670.
0200
050.
2815
68-3
.22
0.29
2.31
2.67
Eas
tBar
ton-
890.
1536
30.
0048
9.25
788
0.26
910.
4369
50.
0096
0.08
704
0.00
3223
8754
2364
2623
3742
1687
6098
0.28
2055
0.00
0009
0.00
0466
0.01
3509
0.28
2048
-7.9
50.
331.
662.
21E
astB
arto
n-10
00.
1591
90.
0034
10.3
9118
0.25
170.
4736
60.
0113
0.12
821
0.00
4224
4738
2470
2225
0050
2438
7410
20.
2810
400.
0000
080.
0002
790.
0077
640.
2810
27-8
.30
0.28
3.02
3.47
Eas
tBar
ton-
104
0.16
109
0.00
3510
.261
120.
2045
0.46
166
0.00
880.
1263
00.
0025
2467
3824
5918
2447
3824
0444
990.
2811
690.
0000
090.
0000
290.
0013
570.
2811
68-1
.92
0.32
2.83
3.11
Eas
tBar
ton-
105
0.10
238
0.00
224.
4552
20.
0935
0.31
543
0.00
640.
0738
50.
0015
1668
4017
2318
1767
3214
4028
106
Eas
tBar
ton-
106
0.15
984
0.00
3410
.187
510.
2080
0.46
195
0.00
910.
1214
30.
0023
2454
3824
5218
2448
4023
1640
100
Eas
tBar
ton-
108
0.16
007
0.00
3810
.053
050.
2243
0.45
515
0.00
910.
1133
70.
0026
2456
4024
4020
2418
4021
7148
980.
2811
500.
0000
100.
0003
620.
0100
880.
2811
33-2
.70
0.35
2.88
3.17
Eas
tBar
ton-
109
0.15
680
0.00
339.
9431
60.
1943
0.45
954
0.00
880.
1128
70.
0021
2421
3624
3018
2438
3821
6238
101
0.28
1069
0.00
0008
0.00
0457
0.01
3320
0.28
1048
-5.9
90.
263.
003.
37K
ingo
onya
Wes
t-10.
1454
40.
0029
7.92
089
0.13
840.
3955
00.
0069
0.11
109
0.00
2122
9336
2222
1621
4832
2129
3894
0.28
1935
0.00
0010
0.00
0386
0.01
0640
0.28
1925
0.12
0.35
1.82
2.13
Kin
goon
ya W
est-2
0.16
307
0.00
329.
2812
10.
1598
0.41
287
0.00
720.
1070
20.
0018
2488
3423
6616
2228
3220
5532
90K
ingo
onya
Wes
t-40.
1573
00.
0031
9.59
398
0.16
090.
4423
00.
0076
0.12
431
0.00
2224
2734
2397
1623
6134
2368
3897
0.28
1210
0.00
0006
0.00
0126
0.00
4662
0.28
1204
-4.1
60.
202.
783.
13K
ingo
onya
Wes
t-60.
1585
50.
0039
9.70
505
0.24
770.
4425
00.
0104
0.08
863
0.00
3524
4042
2407
2423
6246
1716
6697
0.28
2191
0.00
0013
0.00
0353
0.01
0035
0.28
2184
2.59
0.46
1.47
1.75
Kin
goon
ya W
est-7
0.15
894
0.00
3110
.144
280.
2106
0.46
175
0.00
970.
1095
70.
0022
2444
3424
4820
2447
4221
0240
100
0.28
1253
0.00
0010
0.00
2376
0.10
4330
0.28
1142
-2.9
80.
352.
893.
17K
ingo
onya
Wes
t-14
0.16
082
0.00
329.
8959
30.
1735
0.44
623
0.00
790.
0289
90.
0005
2464
3424
2516
2378
3657
810
970.
2819
890.
0000
100.
0006
070.
0171
520.
2819
75-1
.92
0.34
1.76
2.13
Kin
goon
ya W
est-1
90.
1594
80.
0031
10.3
1968
0.19
850.
4693
60.
0093
0.12
328
0.00
2324
5034
2464
1824
8140
2350
4010
10.
2811
950.
0000
090.
0000
910.
0037
210.
2811
91-0
.71
0.31
2.80
3.04
Kin
goon
ya W
est-2
00.
1598
70.
0032
10.2
6029
0.17
870.
4654
50.
0081
0.13
423
0.00
2424
5434
2459
1624
6436
2546
4410
00.
2812
300.
0000
090.
0002
830.
0102
720.
2812
17-0
.11
0.30
2.77
2.99
Kin
goon
ya W
est-3
30.
1594
20.
0033
10.2
3240
0.23
700.
4650
10.
0108
0.11
803
0.00
3224
5036
2456
2224
6248
2255
5810
00.
2821
980.
0000
110.
0006
850.
0184
670.
2821
835.
150.
391.
481.
67K
ingo
onya
Wes
t-51
0.16
496
0.00
3410
.771
240.
2063
0.47
379
0.00
900.
1341
30.
0026
2507
3625
0418
2500
4025
4446
100
0.28
2040
0.00
0011
0.00
0542
0.01
5854
0.28
2027
1.53
0.39
1.69
1.97
Kin
goon
ya W
est-6
20.
1603
80.
0032
10.0
7310
0.18
420.
4556
90.
0084
0.11
000
0.00
2124
6034
2442
1624
2038
2109
3898
0.28
2447
0.00
0005
0.00
0859
0.02
7275
0.28
2437
1.75
0.19
1.13
1.46
Kin
goon
ya W
est-6
70.
1033
50.
0033
4.25
825
0.13
130.
2989
00.
0064
0.08
291
0.00
2216
8560
1685
2616
8632
1610
4210
00.
2811
960.
0000
080.
0015
230.
0625
290.
2811
25-3
.16
0.27
2.91
3.20
Kin
goon
ya W
est-7
70.
1573
20.
0033
9.41
158
0.19
490.
4346
20.
0088
0.08
521
0.00
2024
2736
2379
2023
2740
1653
3696
0.28
2950
0.00
0013
0.00
1962
0.05
3647
0.28
2946
8.40
0.46
0.44
0.63
Kin
goon
ya W
est-8
00.
1586
60.
0031
10.1
2319
0.20
200.
4625
90.
0094
0.12
274
0.00
2424
4134
2446
1824
5142
2340
4410
00.
2823
900.
0000
130.
0007
680.
0211
440.
2823
801.
260.
461.
211.
54K
ingo
onya
Wes
t-82
0.11
289
0.00
235.
2351
00.
1008
0.33
618
0.00
630.
0865
30.
0017
1846
3818
5816
1868
3016
7732
101
0.28
1244
0.00
0012
0.00
0342
0.01
5011
0.28
1228
0.09
0.42
2.75
2.98
Kin
goon
ya W
est-8
60.
1619
10.
0034
10.2
5094
0.20
290.
4589
10.
0089
0.09
714
0.00
2024
7636
2458
1824
3540
1874
3698
0.28
1230
0.00
0010
0.00
0892
0.02
7323
0.28
1194
-8.9
80.
352.
813.
29K
ingo
onya
Wes
t-87
0.15
599
0.00
319.
6877
40.
1850
0.45
012
0.00
880.
0151
60.
0003
2413
3424
0618
2396
4030
46
990.
2811
150.
0000
120.
0007
710.
0241
850.
2810
79-4
.42
0.42
2.96
3.29
Kin
goon
ya W
est-9
40.
1625
80.
0037
10.3
3188
0.23
100.
4605
10.
0096
0.12
406
0.00
2824
8340
2465
2024
4242
2364
5098
0.28
1197
0.00
0007
0.00
0437
0.01
4225
0.28
1177
-2.3
80.
252.
823.
11La
keIfo
uld-
010.
1561
10.
0031
9.70
498
0.17
320.
4508
90.
0081
0.12
471
0.00
1924
1434
2407
1623
9936
2375
3499
0.28
1223
0.00
0011
0.00
0741
0.02
0735
0.28
1188
-0.3
80.
392.
813.
04La
keIfo
uld-
060.
1602
30.
0032
10.1
3347
0.18
450.
4586
80.
0084
0.11
968
0.00
1824
5834
2447
1624
3438
2285
3299
0.28
2130
0.00
0012
0.00
0365
0.01
2209
0.28
2122
1.19
0.42
1.56
1.86
Lake
Ifoul
d-08
0.10
527
0.00
244.
3378
50.
0889
0.29
887
0.00
560.
0860
60.
0015
1719
4217
0116
1686
2816
6928
980.
2820
350.
0000
150.
0011
380.
0395
230.
2820
09-0
.42
0.53
1.72
2.05
Lake
Ifoul
d-09
0.18
243
0.00
4612
.875
620.
3139
0.51
186
0.01
150.
1343
50.
0052
2675
4226
7122
2665
5025
4892
100
0.28
1571
0.00
0008
0.00
1231
0.03
7330
0.28
1531
-5.6
60.
292.
372.
78La
keIfo
uld-
100.
1129
80.
0076
4.66
101
0.29
090.
2992
20.
0075
0.08
629
0.00
2018
4812
417
6052
1687
3816
7336
910.
2811
860.
0000
090.
0007
480.
0251
220.
2811
482.
640.
322.
862.
99La
keIfo
uld-
110.
1057
10.
0053
4.42
292
0.20
750.
3035
20.
0087
0.08
795
0.00
3217
2794
1717
3817
0944
1704
6099
0.28
1621
0.00
0008
0.00
1531
0.05
2870
0.28
1567
-1.4
40.
272.
322.
62La
keIfo
uld-
120.
1538
80.
0031
9.25
480
0.17
230.
4362
40.
0081
0.12
082
0.00
2123
8936
2364
1823
3436
2305
3898
0.28
1636
0.00
0017
0.00
1082
0.03
6270
0.28
1601
-3.0
10.
602.
272.
62La
keIfo
uld-
140.
1052
40.
0024
4.03
962
0.08
430.
2784
50.
0054
0.07
071
0.00
1217
1942
1642
1615
8428
1381
2292
0.28
2139
0.00
0010
0.00
0599
0.01
9673
0.28
2127
-0.1
80.
341.
551.
90La
keIfo
uld-
160.
1499
00.
0036
8.72
845
0.14
680.
4223
20.
0071
0.11
841
0.00
2223
4542
2310
1622
7132
2262
3897
0.28
1805
0.00
0008
0.00
0402
0.01
3810
0.28
1796
-7.7
00.
292.
002.
52La
keIfo
uld-
190.
1534
90.
0030
8.47
103
0.15
680.
4004
60.
0075
0.11
201
0.00
1823
8534
2283
1621
7134
2146
3491
0.28
2171
0.00
0013
0.00
0607
0.02
1408
0.28
2158
2.80
0.46
1.51
1.77
Lake
Ifoul
d-20
0.10
529
0.00
334.
3436
30.
1036
0.29
921
0.00
600.
0869
10.
0018
1719
5817
0220
1687
3016
8534
980.
2812
180.
0000
130.
0004
420.
0165
190.
2811
98-2
.28
0.46
2.80
3.08
-49-
Chapter 2 Supplementary Material
Ana
lysi
sIs
otop
e R
atio
sA
ges
(Ma)
Isot
ope
Rat
ios
Sch
erer
et a
l. 20
01 d
ecay
con
stan
t20
7 Pb/20
6 Pb
207 Pb
/235 U
206 Pb
/238 U
208 Pb
/232 Th
207 Pb
/206 P
b20
7 Pb/23
5 U20
6 Pb/23
8 U20
8 Pb/23
2 Th%
con
176 H
f/177 H
f1
SE
176 Lu
/177 H
f17
6 Yb/17
7 Hf
Hf i
Hf
1 S
ET D
M(G
a)T D
MC
rust
al
(Ga)
Lake
Ifoul
d-26
0.10
383
0.00
244.
1834
00.
0904
0.29
226
0.00
560.
0848
00.
0015
1694
4416
7118
1653
2816
4528
980.
2814
800.
0000
100.
0006
540.
0259
040.
2814
59-8
.23
0.33
2.46
2.95
Lake
Ifoul
d-27
0.15
618
0.00
329.
6451
80.
1793
0.44
800
0.00
820.
1236
20.
0021
2415
3624
0118
2386
3623
5638
990.
2816
170.
0000
090.
0014
190.
0469
840.
2815
71-4
.79
0.32
2.32
2.71
Lake
Ifoul
d-28
0.10
928
0.00
444.
5551
10.
1769
0.30
231
0.00
810.
0865
20.
0028
1787
7617
4132
1703
4016
7752
950.
2811
920.
0000
050.
0000
710.
0028
290.
2811
89-1
.91
0.18
2.80
3.08
Lake
Ifoul
d-29
0.15
570
0.00
329.
5701
40.
1787
0.44
583
0.00
830.
1269
40.
0022
2409
3623
9418
2377
3824
1538
990.
2815
630.
0000
100.
0013
260.
0434
940.
2815
18-4
.57
0.35
2.39
2.77
Lake
Ifoul
d-31
0.15
074
0.00
318.
4628
00.
1515
0.40
720
0.00
730.
1152
70.
0018
2354
3622
8216
2202
3422
0532
940.
2821
240.
0000
080.
0006
120.
0205
430.
2821
112.
380.
281.
571.
84La
keIfo
uld-
330.
1027
10.
0021
4.20
274
0.07
550.
2968
30.
0053
0.08
705
0.00
1416
7438
1675
1416
7626
1687
2610
00.
2811
980.
0000
090.
0000
600.
0027
730.
2811
95-3
.08
0.31
2.80
3.11
Lake
Ifoul
d-35
0.14
283
0.00
338.
0470
50.
1796
0.40
866
0.00
850.
1134
60.
0029
2262
4222
3620
2209
3821
7252
980.
2815
920.
0000
080.
0013
880.
0406
250.
2815
48-6
.08
0.27
2.35
2.77
Lake
Ifoul
d-36
0.10
446
0.00
264.
3522
20.
1047
0.30
218
0.00
640.
0841
80.
0018
1705
4617
0320
1702
3216
3434
100
0.28
1250
0.00
0009
0.00
0284
0.01
0358
0.28
1238
-3.6
90.
302.
743.
08La
keIfo
uld-
400.
1098
40.
0062
4.62
723
0.24
950.
3057
40.
0102
0.09
513
0.00
5417
9710
417
5446
1720
5018
3710
096
0.28
1749
0.00
0010
0.00
0504
0.01
6498
0.28
1733
1.19
0.35
2.08
2.34
Lake
Ifoul
d-43
0.10
514
0.00
254.
4019
20.
1031
0.30
375
0.00
650.
0862
30.
0019
1717
4417
1320
1710
3216
7236
100
0.28
1565
0.00
0011
0.00
0548
0.01
8245
0.28
1546
-3.3
40.
392.
342.
70La
keIfo
uld-
450.
1075
30.
0022
4.62
052
0.08
390.
3116
70.
0057
0.08
858
0.00
1417
5838
1753
1617
4928
1715
2699
0.28
1742
0.00
0008
0.00
0294
0.01
0529
0.28
1739
-24.
460.
282.
083.
05La
keIfo
uld-
460.
1526
80.
0031
9.03
289
0.17
250.
4291
10.
0082
0.11
895
0.00
2023
7636
2341
1823
0236
2272
3697
0.28
1731
0.00
0010
0.00
0714
0.02
5065
0.28
1707
1.48
0.34
2.12
2.36
Lake
Ifoul
d-47
0.16
073
0.00
3910
.042
370.
2320
0.45
318
0.00
960.
1226
50.
0032
2463
4224
3922
2409
4223
3856
980.
2812
120.
0000
080.
0002
300.
0090
490.
2812
02-2
.35
0.28
2.79
3.08
Lake
Ifoul
d-48
0.09
510
0.00
213.
4650
00.
0747
0.26
427
0.00
530.
0731
10.
0014
1530
4215
1916
1512
2814
2626
990.
2812
760.
0000
100.
0006
210.
0211
290.
2812
471.
260.
352.
732.
92La
keIfo
uld-
520.
1613
10.
0037
10.3
9095
0.22
420.
4672
20.
0095
0.13
011
0.00
3124
6940
2470
2024
7142
2472
5410
00.
2817
080.
0000
110.
0004
920.
0181
430.
2816
94-4
.16
0.39
2.14
2.54
Lake
Ifoul
d-53
0.10
459
0.00
254.
3634
50.
0970
0.30
259
0.00
580.
0909
00.
0019
1707
4617
0518
1704
2817
5936
100
0.28
1271
0.00
0008
0.00
0417
0.01
4818
0.28
1251
1.56
0.27
2.72
2.90
Lake
Ifoul
d-56
0.10
499
0.00
284.
4186
60.
1047
0.30
533
0.00
590.
0855
80.
0022
1714
5017
1620
1718
3016
6040
100
0.28
1547
0.00
0010
0.00
0671
0.02
2983
0.28
1525
-6.1
30.
342.
372.
80La
keIfo
uld-
620.
1610
00.
0034
10.1
7994
0.19
420.
4585
90.
0086
0.13
087
0.00
2524
6636
2451
1824
3338
2486
4699
0.28
1571
0.00
0010
0.00
0745
0.02
5366
0.28
1547
-5.2
10.
352.
342.
75La
keIfo
uld-
630.
1606
10.
0033
9.93
185
0.19
240.
4485
10.
0086
0.12
796
0.00
2424
6236
2428
1823
8938
2434
4297
0.28
1180
0.00
0010
0.00
0037
0.00
1623
0.28
1178
-1.1
10.
352.
823.
07La
keIfo
uld-
64C
0.12
544
0.00
295.
9602
50.
1227
0.34
468
0.00
640.
1000
10.
0022
2035
4219
7018
1909
3019
2740
940.
2812
320.
0000
070.
0004
060.
0124
540.
2812
130.
030.
252.
773.
00La
keIfo
uld-
64R
0.11
272
0.00
454.
8273
00.
1621
0.31
061
0.00
670.
0896
00.
0020
1844
7417
9028
1744
3417
3436
95La
keIfo
uld-
650.
1595
40.
0034
10.2
6127
0.20
460.
4665
00.
0090
0.13
035
0.00
2624
5138
2459
1824
6840
2477
4610
10.
2812
100.
0000
080.
0000
960.
0036
270.
2812
06-1
0.00
0.28
2.78
3.30
Lake
Ifoul
d-66
0.16
099
0.00
3310
.279
760.
1976
0.46
313
0.00
890.
1279
40.
0022
2466
3624
6018
2453
4024
3340
990.
2812
460.
0000
070.
0006
000.
0191
160.
2812
18-0
.04
0.23
2.77
2.99
Lake
Ifoul
d-68
0.09
891
0.00
203.
7892
40.
0724
0.27
787
0.00
530.
0776
30.
0014
1604
3815
9016
1581
2615
1126
990.
2812
000.
0000
090.
0000
450.
0018
110.
2811
98-0
.41
0.32
2.79
3.03
Lake
Ifoul
d-71
0.15
706
0.00
549.
5627
50.
2637
0.44
157
0.00
920.
1232
50.
0026
2424
6023
9426
2358
4223
4948
970.
2817
010.
0000
110.
0012
680.
0449
710.
2816
63-3
.60
0.39
2.19
2.56
Lake
Ifoul
d-72
0.14
181
0.00
297.
4882
60.
1373
0.38
301
0.00
690.
1094
50.
0019
2249
3621
7216
2090
3220
9934
930.
2812
450.
0000
070.
0004
860.
0157
430.
2812
23-0
.50
0.25
2.76
3.00
Lake
Ifoul
d-73
0.15
920
0.00
3310
.031
640.
1780
0.45
704
0.00
800.
1292
70.
0023
2447
3624
3816
2426
3624
5742
990.
2812
360.
0000
100.
0002
650.
0091
790.
2812
25-4
.45
0.34
2.76
3.12
Lake
Ifoul
d-74
0.15
737
0.00
3210
.107
740.
1898
0.46
587
0.00
870.
1325
60.
0023
2428
3624
4518
2465
3825
1640
102
0.28
1369
0.00
0021
0.00
1896
0.07
4297
0.28
1280
2.09
0.74
2.69
2.85
Lake
Ifoul
d-75
0.15
974
0.00
3310
.062
320.
1838
0.45
690
0.00
820.
1301
30.
0022
2453
3624
4116
2426
3624
7340
990.
2811
870.
0000
100.
0000
160.
0007
320.
2811
86-1
.70
0.34
2.81
3.08
Lake
Ifoul
d-76
0.14
842
0.00
318.
8488
20.
1723
0.43
242
0.00
830.
1276
70.
0023
2328
3623
2318
2317
3824
2942
100
0.28
1230
0.00
0010
0.00
0165
0.00
5477
0.28
1222
0.16
0.34
2.76
2.98
Lake
Ifoul
d-77
0.15
758
0.00
349.
9869
90.
2032
0.45
969
0.00
900.
1311
80.
0029
2430
3824
3418
2438
4024
9152
100
0.28
1326
0.00
0008
0.00
1277
0.04
1551
0.28
1269
-1.0
50.
282.
712.
96La
keIfo
uld-
810.
0975
90.
0028
3.69
197
0.09
670.
2743
80.
0056
0.08
299
0.00
1815
7954
1570
2015
6328
1611
3499
0.28
1215
0.00
0010
0.00
0032
0.00
1523
0.28
1214
-0.6
80.
352.
773.
02La
keIfo
uld-
850.
1576
40.
0033
9.74
328
0.18
190.
4483
00.
0082
0.13
310
0.00
2424
3136
2411
1823
8836
2526
4298
0.28
1921
0.00
0012
0.00
0650
0.02
1130
0.28
1902
4.32
0.42
1.86
2.04
Lake
Ifoul
d-90
0.15
731
0.00
3410
.136
040.
2077
0.46
734
0.00
930.
1268
00.
0025
2427
3824
4718
2472
4024
1344
102
0.28
1236
0.00
0008
0.00
0358
0.01
1598
0.28
1219
-0.4
50.
282.
773.
00
Chapter 3
This chapter is published as:
Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Belousova, E.A., 2011. U-Pb, Lu-Hf and depositi onal ti ming of metasedimentary rocks in the western Gawler Craton: Implicati ons for
Proterozoic reconstructi on models. Precambrian Research, 184, 43-62.
-53-
U–Pb, Lu–Hf and Sm–Nd isotopic constraints on provenance and depositional
timing of metasedimentary rocks in the western Gawler Craton:
Implications for Proterozoic reconstruction models
Katherine E. Howarda,∗, Martin Handa, Karin M. Barovicha, Justin L. Paynea, Elena A. Belousovab
a Centre for Tectonics, Resources and Exploration, University of Adelaide, Adelaide, SA 5005, Australiab GEMOC National Key Centre, Department of Earth and Planetary Sciences, Macquarie University, NSW 2109, Australia
a r t i c l e i n f o
Article history:
Received 23 February 2010
Received in revised form 18 October 2010
Accepted 19 October 2010
Keywords:
Provenance
Proterozoic
Nd isotopes
Hf isotopes
Zircon
Gawler Craton
a b s t r a c t
The Gawler Craton forms the bulk of the South Australian Craton and occupies a pivotal location that
links rock systems in Antarctica to those in northern Australia. The western Gawler Craton is a virtu-
ally unexposed region where the timing of basin development and metamorphism is largely unknown,
making the region ambiguous in the context of models seeking to reconstruct the Australian Proterozoic.
Detrital zircon data from metasedimentary rocks in the central Fowler Domain in the western Gawler
Craton provide maximum depositional ages between 1760 and 1700 Ma, with rare older detrital com-
ponents ranging in age up to 3130 Ma. In the bulk of samples, εNd(1700 Ma) values range between −4.3
and −3.8. The combination of these data suggest on average, comparatively evolved but age-restricted
source regions. Lu–Hf isotopic data from the ca 1700 Ma aged zircons provide a wide range of values
(εHf(1700 Ma) +6 to −6). Monazite U–Pb data from granulite-grade metasedimentary rocks yield metamor-
phic ages of 1690–1670 Ma. This range overlaps with and extends the timing of the widespread Kimban
Orogeny in the Gawler Craton, and provides minimum depositional age constraints, indicating that basin
development immediately preceded medium to high grade metamorphism.
The timing of Paleoproterozoic basin development and metamorphism in the western Gawler Craton
coincides with that in the northern and eastern Gawler Craton, and also in the adjacent Curnamona
Province, suggesting protoliths to the rocks within the Fowler Domain may have originally formed part of
a large ca 1760–1700 Ma basin system in the southern Australian Proterozoic. Provenance characteristics
between these basins are remarkably similar and point to the Arunta Region in the North Australian
Craton as a potential source. In this context there is little support for tectonic reconstruction models
that: (1) suggest components of the Gawler Craton accreted together at different stages in the interval ca
1760–1680 Ma; and (2) that the North Australian Craton and the southern Australian Proterozoic were
separate continental fragments between 1760 and 1700 Ma.
© 2010 Elsevier B.V. All rights reserved.
1. Introduction
The role that sedimentary provenance studies play in con-
straining reconstruction models has been recognised by numerous
authors. Provenance studies in metamorphic terrains often use sim-
ilarities in detrital zircon age spectra, and geochemical and isotopic
compositions to link source regions to sedimentary basins or to
correlate once contiguous ancient sedimentary basins, thus provid-
ing constraints on palaeogeographic reconstructions (e.g. Patchett
et al., 1999; Rainbird et al., 2001; Dickinson and Gehrels, 2003;
∗ Corresponding author. Tel.: +61 8 8303 4971.
E-mail address: [email protected] (K.E. Howard).
Fitzsimons and Hulscher, 2005; Samson et al., 2005; Talavera-
Mendoza et al., 2005; Cawood et al., 2007; Kirkland et al., 2007;
Howard et al., 2009).
Currently, several models exist for the reconstruction of Pale-
oproterozoic Australia (Betts and Giles, 2006; Betts et al., 2002;
Dawson et al., 2002; Fitzsimons, 2003; Giles et al., 2002, 2004;
Myers et al., 1996; Payne et al., 2009; Wade et al., 2006). The
majority of these models involve collision or accretion of separate
continental domains to build up a broader continental system. Such
models depend crucially on geological constraints that establish
the likelihood that accretion and collision actually occurred (e.g.
Payne et al., 2010). These constraints include developing a com-
positional and temporal framework for sedimentary basins that
identify potential source regions and provide palaeogeographical
constraints.
0301-9268/$ – see front matter © 2010 Elsevier B.V. All rights reserved.doi:10.1016/j.precamres.2010.10.002
-54-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 1. Simplified solid geology of the Gawler Craton (after Fairclough et al., 2003; Payne et al., 2006). Inset location of the Gawler Craton and other Proterozoic terrains
in Australia (after Myers et al., 1996; Payne et al., 2006). AR, Arunta Region; CP, Curnamona Province, GC, Gawler Craton; MI, Mt Isa Province; MP, Musgrave Province; PC,
Pilbara Craton; YG, Yilgarn Craton.
Unfortunately, many parts of Proterozoic Australia have poor
geological constraints, including critical regions at the postulated
margins of cratons. In most cases this lack of data reflects the
paucity of outcrop. As a consequence, existing reconstruction
models are often very poorly constrained. A further consequence
of the lack of outcrop is that regional geological boundaries
are frequently only geophysically defined (Daly et al., 1998;
Fairclough et al., 2003), which do not necessarily relate to
variations in age and origin of the crustal domains they sepa-
rate.
One such geophysically defined area is the Fowler Domain in
the western Gawler Craton (Figs. 1 and 2). Due to the paucity
of outcrop (<1%), the tectonic history of the Fowler Domain is
largely unknown. Despite this, its role in the tectonic development
of the southern Australian Proterozoic has been discussed by a
number of workers (Betts et al., 2008; Daly et al., 1998; Dawson
et al., 2002; Direen et al., 2005; Teasdale, 1997; Thomas et al.,
2008). Daly et al. (1998) suggest that the Fowler Domain records
deformation and metamorphism associated with the development
of a SE-dipping Palaeo-Mesoproterozoic aged subduction system
on the northwestern margin of the proto-Gawler Craton that
resulted in collision of Archean rocks of the Yilgarn Craton with
the Meso-Archean core of the Gawler Craton. Others (e.g. Dawson
et al., 2002), added to this model by suggesting the Karari Shear
Zone (Fig. 1), was the leading edge of the convergent margin, and
that the rocks northwest of the Karari Shear Zone were a part of a
micro-continent which included the proto-Yilgarn Craton (Fig. 1).
In contrast, Betts and Giles (2006) suggested the Fowler Domain
was accreted to the rest of the Gawler Craton by a north-dipping
subduction system at around 1670 Ma. Other workers consider
the steeply dipping crustal-scale shear zones within the Fowler
Domain to be evidence of a strike-slip dominated regime that
-55-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 2. Total magnetic intensity image of the western Gawler Craton including the Fowler Domain and interpreted major shear zones. The Fowler Domain lies between the
Tallacootra and Coorabie Shear Zones. Drill hole samples used in this study are displayed and labelled. Previously collected age data are displayed. *Fanning et al. (2007),
Swain et al. (2005b).
reworked an existing orogenic belt (Direen et al., 2005; Stewart
et al., 2009; Thomas et al., 2008).
Although these models attempt to explain the gross architecture
of the Fowler Domain and relate it to the broad scale tectonics of
southern Australian Proterozoic assembly, there is very little basic
geological data to constrain the timing of deposition of sedimentary
rocks, and their subsequent medium to high grade metamorphism.
This study utilises detrital zircon U–Pb and Lu–Hf isotopic data,
bulk rock Sm–Nd isotopic and geochemical data with metamorphic
monazite U–Pb age data to characterise the provenance and to con-
strain the depositional interval of sedimentary protoliths within the
Fowler Domain. The data allow the Fowler Domain to be assessed
in the context of other metasedimentary-bearing domains in the
southern Australian Proterozoic.
2. Geological background
The Gawler Craton (Fig. 1) consists of a Meso- to Neo-Archean
(3150–2500 Ma) to Paleoproterozoic (ca 2000–1850 Ma) base-
ment which is intruded and overlain by late Paleoproterozoic
(1790–1600 Ma) to early Mesoproterozoic (1600–1550 Ma) rocks
(Daly et al., 1998; Fraser et al., 2010; Hand et al., 2007; Swain
et al., 2005a). Neoproterozoic and Phanerozoic sedimentary rocks
and sediments overlie most of the craton, greatly restricting study
of crustal composition and tectonothermal evolution (Ferris et al.,
2002).
Recent work has identified 3150 Ma granitic basement to Neo-
Archean metasedimentary lithologies in the Sleaford Complex.
The extent of this Meso-Archean basement in other parts of the
craton is presently unknown. The Sleaford Complex, located in
the south of the craton, and the Mulgathing Complex situated
in the mid-north of the craton (Fig. 1) are thought to be a part
of a single 2560–2500 Ma domain based on geochemical, iso-
topic and geochronological similarities (Hand et al., 2007; Swain
et al., 2005a). These complexes are composed of metasedimentary
lithologies and felsic, ultra-mafic and mafic volcanics (Hand et al.,
2007; Swain et al., 2005a).
Following a period of apparent tectonic quiescence, between
ca 2400 and 2020 Ma, the protoliths to the granodioritic Miltalie
Suite were intruded at 2020–2000 Ma in the eastern part of the
craton (Daly et al., 1998; Fanning et al., 2007; Howard et al., 2009).
The Miltalie Suite is overlain by shallow marine succession of the
Hutchison Group. The minimum depositional age of the Hutchison
Group is interpreted to be 1866 ± 10 Ma, which is the U–Pb zir-
con age of the volcanic Bosanquet Formation. This is interpreted to
occur at the top of the Hutchison Group (Daly et al., 1998; Fanning
et al., 2007; Rankin et al., 1990). However, recent isotopic work
suggests that parts of the Hutchison Group may be younger than
ca 1780 Ma, highlighting ambiguities in the current understand-
ing of the Hutchison Group stratigraphy (Hand et al., 2007). To the
east of the Hutchison Group the 1850 Ma Donington Suite volu-
metrically dominates the southeastern Gawler Craton (Ferris et al.,
2002; Hoek and Schaefer, 1998; Reid et al., 2008). The Doning-
ton Suite intrudes metasedimentary packages deposited before ca
1870–1850 Ma (Howard et al., 2009), and was associated with the
Cornian Orogeny, a short-lived (1850–1847 Ma) cycle of shortening
and high grade metamorphism followed by extension (Reid et al.,
2008). The relationship between the Donington Suite and the older
parts of the Hutchison Group was obscured by tectonic reactivation
during the 1730–1690 Ma Kimban Orogeny (Hand et al., 2007).
After the Cornian Orogeny, widespread sedimentation occurred
over much of the craton (Daly et al., 1998; Payne et al., 2006). In
the eastern Gawler Craton, the Myola Volcanics and associated sed-
iments were deposited at around 1791 ± 4 Ma (Fanning et al., 1988).
Interbedded Tidnamurkuna Volcanics of the Peake and Denison
Inliers (Fig. 1) in the northeastern part of the craton, constrain the
depositional timing of the associated sedimentary rocks to approxi-
mately 1774 ± 16 Ma in age (Fanning et al., 2007). This was followed
by further widespread sedimentation. In the south eastern Gawler
Craton (Fig. 1), this included the 1767 ± 17 Ma protoliths to the Price
Metasediments (Oliver and Fanning, 1997), the ca 1763–1741 Ma
Wallaroo Group (Fanning et al., 2007), the 1756 ± 8 Ma Moon-
abie Formation (Jagodzinski, 2005) and the 1740 Ma McGregor
Volcanics (Fanning et al., 1988). In the north west of the Craton,
-56-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
protoliths to the ca 1750 Ma metasedimentary rocks of the Mt
Woods Domain were deposited (Jagodzinski et al., 2006). In the
northern Gawler Craton, also known as the Nawa Domain (Fig. 1),
metasedimentary rocks intersected in drillcore were deposited in
the interval 1740–1720 Ma (Payne et al., 2006; Payne et al., 2008).
Payne et al. (2006) have shown with geochemical and Nd isotopic
data that these metasedimentary rocks are too enriched and too
isotopically juvenile to have been derived from the erosion of the
currently preserved >1740 Ma rocks of the Gawler Craton. Instead
the authors suggest that ca 1800–1700 Ma rocks in the Aileron
Province of the Arunta Region in the North Australian Craton may
have been a likely source region.
The Kimban Orogeny is a widespread tectonic event that
occurred in the Gawler Craton from 1730 to 1690 Ma (Dutch et al.,
2010; Hand et al., 2007; Payne et al., 2008). The effects of the Kim-
ban Orogeny are recorded in Paleoproterozoic metasedimentary
sequences of the northern Gawler Craton, Mount Woods Domain
and Peak and Denison Inliers (Betts et al., 2003; Hopper, 2001;
Payne et al., 2006, 2008) as well as throughout the eastern and
central parts of the Eyre Peninsular (Fig. 1; Vassallo and Wilson,
2002; Dutch et al., 2010).
In the poorly exposed Fowler Domain of the western Gawler Cra-
ton (Fig. 1), there is limited evidence for the timing of sedimentary
basin development. The majority of the lithological information
is a product of mineral exploration drilling programs. Reconnais-
sance U–Pb zircon dating by Teasdale (1997) from drillcore from the
central Fowler Domain suggests that the protoliths to the metased-
imentary rocks are Paleoproterozoic in age (Fanning et al., 2007).
Minimum age constraints of ca 1715 and 1670 Ma are provided by
Teasdale (1997) and Swain et al. (2005b) using SHRIMP and EMPA
dating of metamorphic monazite.
The Fowler Domain (Fig. 2), is bound by crustal scale shear zones
(Stewart et al., 2009; Thiel and Heinson, 2010; Thomas et al., 2008),
and is defined as a NE to NNE trending, geophysically distinctive
region of highly magnetic metamorphic and igneous rocks (Daly
et al., 1998; Stewart et al., 2009; Teasdale, 1997; Thomas et al.,
2008). To the northwest, the Fowler Domain is separated from the
late Archean Christie Domain by the Tallacootra Shear Zone. To the
east the Fowler Domain is separated from late Paleoproterozoic
rocks of the St Peters Suite (Swain et al., 2008) by the Coorabie
Shear Zone.
Within the Fowler Domain (Fig. 2), four distinct blocks bounded
by crustal scale shear zones have been identified: The Colona, Bar-
ton, Central and Nundroo Blocks (Teasdale, 1997; Thomas et al.,
2008). Although the individual blocks have similarities in their geo-
physical signatures (Stewart et al., 2009; Thomas et al., 2008), they
have contrasting metamorphic grades (Teasdale, 1997; Thomas
et al., 2008).
The Colona Block is the most westerly domain and is bound
by two branches of the 1670 Ma Tallacootra Shear Zone. Litholo-
gies include layered intermediate to mafic intrusive igneous rocks
deformed and metamorphosed to low amphibolite facies (550 ◦C
and 5 kbar; Thomas et al., 2008). U–Pb dating of a metagabbro from
drill hole Colona DDH43 yielded an age of 1727 ± 8 Ma (Fanning
et al., 2007). Granite at Lake Ifould, just west of the Tallacootra
Shear Zone (Fig. 2), gave an age of 1681 ± 15 Ma (Fanning et al.,
2007). Reconnaissance EMPA monazite data suggest that metamor-
phism within the Colona Block may have occurred between 1650
and 1600 Ma (Thomas et al., 2008).
The Barton Block is bound to the east by the Colona Shear Zone
and to the west by the Tallacootra Shear Zone. Drilling has shown
that the Barton Block consists of metasedimentary rocks, grani-
toids and mafic rocks metamorphosed up to the amphibolites to
granulite facies transition (700 ◦C, 7.5 kbar; Teasdale, 1997; Thomas
et al., 2008). U–Pb dating of weakly deformed granite close to the
northern boundary of the Fowler Domain yielded an approximate
age of 1675 Ma (Fanning et al., 2007). Reconnaissance EMPA mon-
azite data from felsic gneisses and metapelites suggest that upper
amphibolite to granulite grade metamorphism and deformation
occurred in the Barton Block at 1606 ± 17 Ma and 1592 ± 18 Ma
(Thomas et al., 2008). However, the presence of a ca 1675 Ma
weakly deformed granite, which has been interpreted to cross
cut the regional structural trend (Teasdale, 1997), suggests that
regional metamorphism occurred prior to 1675 Ma and therefore
the EMPA monazite ages may not be reliable.
The Central Block is bound by the Coorabie Shear Zone to the
east and the Colona Shear Zone to the west. Major lithologies
include felsic intrusives, granitoids and mafic rocks, and there is
little evidence so far for metasedimentary lithologies (Teasdale,
1997; Thomas et al., 2008). Granite at White Gin Rockhole in the
northern Central Block (Fig. 2) has been dated at 1670 ± 9 Ma, and
an orthogneiss from the mid-Central Block gives a crystallisation
age of 1568 ± 11 Ma (Fanning et al., 2007). The presence of this
orthogneiss implies that some magmatism is Mesoproterozoic in
age.
The non-outcropping Nundroo Block is bound by two branches
of the Coorabie Shear Zone. Dominant lithologies include inter-
mediate to mafic rocks interlayered with metapelitic gneisses
(Teasdale, 1997). Metamorphism in the Nundroo Block was up to
granulite grade (800 ◦C, 9 kbar; Thomas et al., 2008). Metamorphic
zircons from mafic granulite in Nundroo DDH2 yielded a U–Pb zir-
con age of 1547 ± 9 (Fanning et al., 2007). Foliated granite from
drill hole NDR 13 in the Nundroo Block yielded a U–Pb zircon
age of 1586 ± 9 Ma (Fanning et al., 2007). Reconnaissance EMPA
monazite dating suggests metamorphism in the Nundroo Block
occurred between 1557 ± 15 Ma and 1471 ± 14 Ma (Thomas et al.,
2008). An undeformed crosscutting pegmatite from Nundroo DDH
2 yielded a U–Pb zircon age of 1489 ± 4 Ma (Fanning et al., 2007).40Ar/39Ar dating of muscovite from the Tallacootra Shear
Zone which dissects the Fowler Domain yielded ages of
1467 ± 11 Ma, 1445 ± 10 Ma and 1441 ± 10 Ma, at Lake Tallacootra,
and 1537 ± 14 Ma and 1478 ± 11 Ma at Lake Ifould (Fraser and
Lyons, 2006). The younger ages are interpreted to be the timing of
either shear zone reactivation or regional cooling (Fraser and Lyons,
2006). Similar ages were also obtained by Swain et al. (2005b) from
EMPA monazite dating in shear zones.
3. Samples and analytical methods
Access to basement rocks is limited in the Fowler Domain and
the bulk of basement information comes from drilling. Samples in
this study were taken from diamond and reverse circulation drill-
holes that were completed as a part of regional mineral exploration
programs. The BAC drill holes were drilled with reverse circulation
methods and the samples for this study are taken from short end
of hole plugs. For this reason the exact depths within the basement
interval for each sample from the BAC drill holes is unknown. Drill
holes that have intersected metasedimentary basement rocks have
narrow diameters ∼4 cm and have limited intervals of basement
intersection (≤6 m, with the exception of TAL20) with variable
recovery. With such short basement intersection intervals, only one
lithology is present in each drillhole.
Typical pelitic assemblages that incorporate biotite, muscovite,
garnet, quartz, sillimanite and cordierite were targeted for sedi-
mentary protoliths (Fig. 3). Sampled drill-holes, drill-hole interval,
sampled lithology and petrological summaries are listed in Table 1,
and the locations of drill-holes are shown in Fig. 2.
3.1. Whole rock geochemistry
Rocks were crushed with a jaw crusher then milled in a tungsten
carbide ring mill to a fine powder at the University of Adelaide. Geo-
-57-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 3. Photomicrographs of typical mineral assemblages in metasedimentary rocks from the Fowler Domain. (a) TAL4 schistosity defined entirely by biotite, (b) TAL20
banded gneiss with layers of biotite alternating with quartz and k-feldspar, (c) BAC18 banded gneissic foliation defined by alternating layers of quartz and feldspar against
bands of sillimanite, biotite and garnet, (d) BAC28 gneissic bands of quartz and feldspar alternating with biotite and rare sillimanite.
chemical analyses were done at Amdel Limited, South Australia. For
the acquisition of major elements, a sub-sample of 0.1 g of analyti-
cal pulp was fused with lithium metaborate followed by dissolution
to give a total solution, which was run on an ICP-OES. Trace and rare
earth element data were acquired from the digestion of 0.2 g sub-
sample of analytical pulp in HF and multi acid digest, the solution
was then run on an ICP-MS and an ICP-OES.
3.2. U–Pb zircon and monazite dating
Analytical techniques for U–Pb isotopic dating of zircon and
monazite follow those of Payne et al. (2006, 2008). Rocks were
crushed with a jaw crusher, and sieved, collecting the 79–300 �m
portion. Separates were obtained using panning, Frantz (at 0.6 nT),
and heavy liquid methods before being handpicked and mounted
into epoxy resin blocks. Prior to analysis zircon grains were
imaged using CL imaging on a Phillips XL-20 SEM with attached
Gatan Cathode Luminescence detector in order to identify detri-
tal domains within the grains. Monazite grains were imaged
prior to analysis via a back-scattered electron on a Phillips XL20
SEM. U–Pb isotopic analyses were obtained using a New Wave
213 nm Nd–YAG laser in a He ablation atmosphere, coupled to
an Agilent 7500cs ICP-MS at the University of Adelaide. U–Pb
fractionation was corrected using the GEMOC GJ1 zircon (TIMS nor-
malisation data 207Pb/206Pb = 608.3 Ma, 206Pb/238U = 600.7 Ma and207Pb/235U = 602.2 Ma; Jackson et al., 2004) and the MAdel mon-
azite standard (TIMS normalisation data 207Pb/206Pb = 490.7 Ma,206Pb/238U = 514.8 Ma and 207Pb/235U = 510.4 Ma; Payne et al.,
2008). Accuracy was checked with an in-house Sri Lankan zircon
standard (BJWP-1, ca 720 Ma) and an in-house monazite stan-
dard (94-222/Bruna-NW, ca 450 Ma). The 207Pb/206Pb grain ages
were used. A number of zircon grains were excluded from analysis
due to metamictisation and small grain size. Detrital cores larger
than 40 �m in size were targeted, as well as some large meta-
morphic rims. Data were processed using the program “Glitter”
developed at Macquaries University, Sydney (Jackson et al., 2004).
In the data interpretation, a <10% discordancy threshold was used
to filter the data. Over the duration of this study the reported aver-
age normalised ages for GJ-1 are 608.0 ± 3.6 Ma, 601.5 ± 0.9 Ma and
602.9 ± 0.9 Ma for the 207Pb/206Pb, 206Pb/238U and 207Pb/235U ratios
respectively (2�, n = 266). The reported average normalised ages for
MAdel are 513.0 ± 1.7 Ma and 510.7 ± 1.6 Ma for the 206Pb/238U and207Pb/235U ages, respectively (2�, n = 55).
3.3. Zircon Hf isotopic analyses
Analytical methods for zircon Hf isotope determination are
described in detail in Griffin et al. (2006) and Howard et al. (2009),
and are summarised below. Analyses were undertaken with a New
Wave/Merchantek UP-213 laser attached to a Nu Plasma multi-
collector ICP-MS at Macquarie University. Most analyses were
obtained using a beam diameter of 55 �m and a 5 Hz repetition
rate resulting in typical Hf signals of 1–5 × 10−11 A. Typical ablation
times were 80–120 s, resulting in pits 40–50 �m deep.
Data were normalised to 179Hf/177Hf = 0.7325, using an expo-
nential correction for mass bias. Interference of 176Lu on 176Hf
is corrected using the Hf mass bias factor and by measuring
the intensity of the interference-free 175Lu isotope and using176Lu/175Lu = 0.02669 (DeBievre and Taylor, 1993) to calculate176Lu/177Hf. Similarly, the interference of 176Yb on 176Hf has been
corrected by measuring the interference-free 172Yb isotope and
using an empirically derived value for 176Yb/172Yb to calculate176Yb/177Hf. The appropriate value of 176Yb/172Yb was determined
by spiking the JMC475 Hf standard with Yb, and finding the value
of 176Yb/172Yb (0.5865) required to yield the value of 176Hf/177Hf
obtained on the pure Hf solution (Griffin et al., 2004). The accu-
racy of the Yb and Lu corrections has been demonstrated by
repeated analysis of standard zircons with a range in 176Yb/177Hf
and 176Lu/177Hf (Griffin et al., 2004). Before and during the analysis
of unknowns, the 91500 and Mud Tank zircons (Griffin et al., 2004)
were analysed to check instrument performance and stability. The
measured 176Lu/177Hf ratios of the zircons have been used to calcu-
late initial 176Hf/177Hf ratios. These age corrections are very small,
and the typical uncertainty on a single analysis of 176Lu/177Hf (+1%)
contributes an uncertainty of <0.05 εHf unit.
Depleted mantle model ages (TDM) have been calcu-
lated using the measured 176Lu/177Hf ratios of the zircon,
(176Hf/177Hf)i = 0.279718 at 4.56 Ga and 176Lu/177Hf = 0.0384
-58-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
48 K.E. Howard et al. / Precambrian Research 184 (2011) 43–62
Tab
le1
Sam
ple
deta
ils.
Dri
llh
ole
Sam
ple
Co
rety
pe
Lo
cati
on
Do
main
Base
men
tin
terv
al(
m)
Sam
ple
din
terv
al(
m)
Min
era
lass
em
bla
ge
Inte
rpre
ted
pro
toli
th
East
ing
No
rth
ing
Fro
mT
oFro
mT
o
TA
L4
R1
47
27
57
Dia
mo
nd
24
60
28
65
61
17
2Fo
wle
r2
5.0
26
.52
5.5
26
.2p
lg-q
tz-g
t-b
i-co
rdsc
his
tSed
imen
tary
TA
L2
0R
14
72
75
9D
iam
on
d2
47
02
86
56
02
72
Fo
wle
r2
6.0
58
.05
7.0
57
.5q
tz-k
spar-
plg
-bi-
sill
-gt
gn
eis
sSed
imen
tary
BA
C1
8R
14
72
78
1E
OH
sam
ple
24
86
14
65
74
43
7Fo
wle
r4
5.0
48
.0E
OH
qtz
-bi-
ksp
ar-
gt-
sill
-plg
gn
eis
sSed
imen
tary
BA
C2
3R
14
72
78
2E
OH
sam
ple
25
03
74
65
73
84
2Fo
wle
r4
8.0
57
.0E
OH
qtz
-ksp
ar-
plg
-bi-
gt-
sill
gn
eis
sSed
imen
tary
BA
C2
8R
14
72
78
3E
OH
sam
ple
25
18
64
65
73
52
0Fo
wle
r5
4.0
57
.0E
OH
qtz
-bi-
sill
-pla
g-g
tg
neis
sSed
imen
tary
BA
C3
3R
14
72
78
4E
OH
sam
ple
25
35
52
65
73
28
8Fo
wle
r1
5.0
51
.0E
OH
qtz
-bi-
sill
-gt
gn
eis
sSed
imen
tary
BA
C4
1R
14
72
78
5E
OH
sam
ple
25
56
70
65
73
10
7Fo
wle
r3
2.0
45
.0E
OH
plg
-bi-
qtz
-sil
l-g
t-il
mg
neis
sSed
imen
tary
CO
L2
0D
R1
47
27
56
Dia
mo
nd
78
22
83
65
36
36
4Fo
wle
r4
3.0
48
.04
6.6
47
.5g
t-b
i-m
us-
qtz
-plg
-ilm
-sil
lg
neis
sSed
imen
tary
(Griffin et al., 2000, 2004). This produces a depleted mantle model
with present day 176Hf/177Hf = 0.28325, similar to that of average
MORB (Nowell et al., 1998). Crustal model ages (TDM(crustal)) have
also been calculated to simulate an average continental crust
magma source using 176Lu/177Hf = 0.015 (Geochemical Earth
Reference Model database, http://www.earthref.org/).
For the calculation of εHf, we have adopted a decay constant
for 176Lu of 1.865 × 10−11 y−1 derived by Scherer et al. (2001). εHf
values for two other decay constants (Blichert-Toft and Albarede,
1997; Bizzarro et al., 2003) are calculated for comparison purposes.
3.4. Whole-rock Sm–Nd isotopic analyses
Analytical techniques for whole rock Sm–Nd isotopic data follow
those of Wade et al. (2005). Sm–Nd isotope analyses were under-
taken at the University of Adelaide. Samples were spiked with a150Nd/147Sm solution. HF was added to the sample in Teflon ‘bombs’
and evaporated. The samples were then oven-heated at 190 ◦C for
5 days in HF in sealed Teflon bombs. The HF was then evaporated,
with HNO3 added shortly before samples were completely dry. 6 M
HCl was added and samples were heated for 2 days at 160 ◦C. Rare
Earth Elements (REEs) were separated in Biorad Polyprep columns,
and were further separated in HDEHP-impregnated Teflon-powder
columns to isolate Sm and Nd. Nd was run on a Finnigan MAT
262 Thermal Ionisation Mass Spectrometer (TIMS) and Sm was
run on a MAT 261 TIMS. The La Jolla and JNdi-1 standards give
long term running averages of 0.511834 ± 0.000018 (2�, n = 96) and
0.512092 ± 0.000016 (2�, n = 164) respectively.
4. Results
4.1. Major and trace element geochemistry of metasedimentary
rocks
Results of major and trace element analyses are shown in
Table 2 and Figs. 3 and 4. The Fowler Domain metasedimentary
rocks have variable amounts of SiO2 (53.6–70.5 wt%) and high
amounts of Al2O3 (14.3–19.2 wt%) suggesting pelitic compositions
(Fig. 4a). Trace element abundances range from similar to signifi-
cantly higher than Post Archean Australian Shale (PAAS; Taylor and
McLennan, 1985). Th values range from 3 to 47 ppm, and Cr from
60 to 160 ppm (Fig. 4b and c). The samples have very high Th/Sc
ratios with the exceptions of TAL 4 which has a low Th/Sc ratio.
Elevated ratios of K2O/Na2O above PAAS (with the exception
of two samples COL20D and TAL 4), suggest chemical maturity of
the sedimentary protoliths. Using the discrimination plot of Roser
and Korsch (1986), metasedimentary rock samples fall within the
tectonic setting of a passive margin, with the exception of COL20D
and TAL 4 which plot with the tectonic setting of an active con-
tinental margin (Fig. 4e). Sedimentary and igneous discrimination
diagrams (Fig. 4f and g) support petrographic interpretations that
the majority of samples are paragneisses (Table 1).
Chondrite-normalised Rare Earth Element (REE) patterns are
shown in Fig. 5. The Fowler Domain samples all display significant
Eu depletion with the exception of sample TAL4. Samples BAC18,
BAC33 and BAC23 are the most enriched in REE and are shaped sim-
ilarly to PAAS except for BAC23 which is slightly depleted in Heavy
Rare Earth Elements (HREEs) compared to PAAS. Samples BAC41,
COL20D, TAL20 and BAC28 have steeper REE pattern than PAAS;
the Light Rare Earth Elements (LREEs) are more enriched while the
HREEs are comparatively depleted. Sample TAL4 has a positive Eu
anomaly and shows depleted LREEs and slightly enriched HREEs
compared to PAAS.
-59-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Table 2Major and trace element analyses for paragneisses of the Fowler Domain.
TAL4 TAL20 BAC18 BAC23 BAC28 BAC33 BAC41 COL20D PAAS
Major (wt%)
SiO2 64.2 58.4 59 65.8 60.6 53.6 70.5 61.6 62.8
TiO2 0.74 0.73 1.04 0.82 0.75 1.2 0.55 0.84 1.0
Al2O3 14.6 18.3 15 16.5 17.9 19.2 14.3 15 18.9
Fe2O3 8.89 9.12 12.3 8.35 8.4 13.8 5.02 10.6 7.2
MnO 0.25 0.165 0.19 0.055 0.2 0.36 0.045 0.205 0.11
MgO 3.58 2.74 3.37 2.17 2.56 5.3 1.37 2.93 2.2
CaO 3.06 0.2 0.38 0.16 0.2 0.09 0.22 1.65 1.3
Na2O 1.82 0.56 0.58 0.4 0.56 0.16 0.7 1.64 1.2
K2O 2.35 4.85 4.6 3.55 3.94 3.08 4.56 3.27 3.7
P2O5 0.01 0.03 0.1 0.06 0.02 0.03 0.06 0.09 0.16
LOI 0.69 4.5 3.31 2.36 5.01 2.43 2.13 1.66
Total 100.19 99.60 99.87 100.23 100.14 99.25 99.46 99.49
Trace (ppm)
Ag 0.2 0.2 0.2 <0.1 <0.1 0.4 <0.1 0.1 –
As 1 <0.5 0.5 <0.5 1 0.5 0.5 1 –
Ba 700 1050 950 1000 750 700 950 650 650
Bi <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 –
Cd <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 <0.1 –
Co 74 42 72 80 68 70 78 56 23
Cr 150 80 100 110 70 160 60 120 110
Cs 1.1 2.8 2.5 0.7 2.4 2.1 1.9 2 15
Cu 46.5 9.5 78 9 8 13.5 5 30 50
Ga 21.5 29 25 20.5 29 31.5 18.5 27.5 20
In 0.05 0.1 0.1 0.1 0.1 0.15 0.05 <0.05 –
Mo 1.1 0.5 0.7 0.8 0.5 0.5 0.7 0.5 1.0
Nb 14 19 18 10.5 10.5 23.5 9.5 13 19
Ni 80 39 54 36 36 68 16 45 55
Pb 5.5 20 20.5 22 19.5 10.5 25.5 17.5 20
Rb 90 120 170 82 115 135 130 100 160
Sb <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 –
Sc 16 14 12 10 14 26 10 8 16
Se <0.5 <0.5 0.5 0.5 <0.5 <0.5 <0.5 <0.5 –
Sr 200 82 84 120 76 34 125 140 200
Te <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 –
Th 3 22.5 47 38 22.5 45.5 29 31 14.6
Tl 0.5 0.8 0.8 0.4 0.7 0.7 0.7 0.5 –
U 0.29 1.05 1.4 0.85 0.49 1 1.75 1.15 3.1
V 100 70 100 60 60 120 40 100 150
W 280 110 290 360 250 200 270 190 2.7
Y 33 14 42.5 24.5 15.5 36 20 14 27
Zn 105 105 105 90 125 240 60 130 85
Zr 180 190 330 350 160 280 270 240 210
REE (ppm)
La 17 39 92 76 41 86 58 58 38
Ce 33 86 180 170 90 170 115 115 80
Pr 4.1 11.5 22.5 23 11.5 22.5 15.5 14 8.9
Nd 14.5 42.5 80 86 42 80 56 50 32
Sm 2.5 7.5 15 15 8 14 9.5 8.5 5.6
Eu 1.15 1.5 2.2 2.5 1.4 2.1 1.65 1.5 1.1
Gd 2.6 5 10 9.5 5.5 9.5 6.5 5 4.7
Tb 0.61 0.75 1.35 1.3 0.76 1.3 0.88 0.64 0.77
Dy 4.9 3.9 7.5 6.5 3.9 7 4.7 3.1 4.4
Ho 1.15 0.6 1.4 1 0.6 1.3 0.76 0.51 1.0
Er 3.5 1.35 4.3 2.3 1.25 3.7 1.95 1.4 2.9
Tm 0.55 0.15 0.65 0.25 0.15 0.5 0.25 0.2 0.40
Yb 3.8 0.9 4.6 1.15 0.7 3.1 1.5 1.15 2.8
Lu 0.54 0.15 0.66 0.17 0.11 0.45 0.23 0.17 0.43
Table 3Sm–Nd isotopic data.
Sample Domain Drill hole Sm (ppm) Nd (ppm) 147Sm/144Nd 143Nd/144Nd 2 S.E. εNd(0)a εNd(T) TDM (Ma)b Age (Ma)
R1472757 Fowler TAL 4 1.6 10.0 0.1001 0.511366 11 −24.8 −3.8 2177 1700
R1472781 Fowler BAC 18 8.6 47.7 0.1086 0.511460 11 −23.0 −3.8 2214 1700
R1472782 Fowler BAC 23 2.8 16.2 0.1055 0.511437 9 −23.4 −3.6 2186 1700
R1472784 Fowler BAC 33 9.2 54.0 0.1028 0.511389 9 −24.4 −3.9 2197 1700
R1472756 Fowler COL20D 5.0 30.5 0.1000 0.511338 8 −25.4 −4.3 2210 1700
a 143Nd/144Nd CHUR(0) = 0.512638, 147Sm/144Nd CHUR(0) = 0.1966.b TDM calculated using the single stage model of Michard et al. (1985).
-60-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 4. Selected Harker-type variation diagrams for Fowler Domain rocks. Metasedimentary rocks are indicated by black squares, PAAS: the post-Archean Australian Shale
(Taylor and McLennan, 1985) is shown for reference as a white square. Plot e is a discrimination diagram of Roser and Korsch (1986). Plot f and g are orthogneiss vs. paragneiss
discrimination plots of Werner (1987).
4.2. Sm–Nd systematics
Results from Sm–Nd isotopic analysis are summarised in Table 3.
εNd(t) is calculated at 1.7 Ga for all samples based on zircon and
monazite U–Pb age constraints (see below). Nd isotopic data are
displayed in Fig. 6. The Fowler Domain metasedimentary samples
plot in a tight group with εNd(1700 Ma) from −3.8 to −4.3.
4.3. U–Pb zircon geochronology
A summary of sample ages is shown in Table 4, U–Pb zircon
data are presented in Supplementary Table 1, and 207Pb/206Pb age
spectra are presented in Fig. 7. Five metasedimentary samples are
used to represent the detrital zircon depositional age spectra in the
Fowler Domain; COL20D, TAL4, BAC18, BAC23 and BAC41.
The zircons obtained from the metasedimentary samples are
mainly sub-rounded, range in size from 50 to 200 �m and have
varying aspect ratios from 1:1.5 to 1:4 (Fig. 8). Zircon grains vary
widely in morphology and internal structure from metamict to per-
fect oscillatory zoning.
Only 7 out of 50 zircon analyses were found to be concordant
from BAC 18. The concordant grains produce one major detrital
zircon peak at ca 1740 Ma. A mean weighted average calculated
from the concordant analyses provides the maximum depositional
age of 1738 ± 15 Ma (MSWD = 0.73).
From BAC 23, 27 out of 90 analyses were found to be within 10%
concordance. A dominant peak exists at ca 1740 Ma and two older
grains record ages of 1818 ± 22 Ma and 2277 ± 20 Ma. A maximum
depositional age of 1717 ± 11 Ma (MSWD = 1.08) is provided by the
mean weighted average of the youngest 17 grains.
From BAC 41, 67 out of 98 analyses were within 10% concor-
dancy. These grains show a dominant peak at ca 1730 Ma with one
older grain aged 1834 ± 19 Ma. A mean weighted average age of
the youngest 48 zircons provided a maximum depositional age of
1722 ± 6 Ma (MSWD = 0.29).
54 from 75 zircon analyses were found to be concordant from
drill hole TAL 4. This detrital zircon histogram is dominated by
one major peak at ca 1705 Ma, with one older grain giving an
age of 2195 ± 20 Ma. A mean weighted average age of 1698 ± 7 Ma
(MSWD = 1.18) calculated from the youngest 47 grains provides the
maximum depositional age.
From COL20D, 30 analyses of 44 were found to be within
10% concordancy. COL20D records the largest age range, with
two major overlapping peaks at ca 1780 Ma and ca 1830 Ma,
and a minor peak at ca 1960. Older individual zircon grains give
ages of 2067 ± 27 Ma, 2118 ± 18 Ma, 2378 ± 17 Ma, 2469 ± 23 Ma,
2544 ± 19 Ma, 2814 ± 17 Ma, 2841 ± 21 Ma and 3131 ± 22 Ma. The
maximum depositional age for COL20D has been calculated from
the mean weighted average age of the youngest 13 grains of
1760 ± 14 Ma (MSWD = 1.20).
-61-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Table 4Zircon and monazite U–Pb ages.
Drill hole Zircon maximum depositional age Zircon metamorphic age Monazite metamorphic age
COL20D 1760 ± 14 Ma (n = 13) 1695 ± 18 Ma (n = 5) 1690 ± 9 Ma (n = 20)
TAL 4 1698 ± 7 Ma (n = 47)
BAC 18 1738 ± 15 Ma (n = 7) 1696 ± 10 Ma (n = 17)
BAC 23 1717 ± 11 Ma (n = 17)
BAC 41 1722 ± 6 Ma (n = 48) 1664 ± 7 Ma (n = 30)
TAL 20 1673 ± 9 Ma (n = 20)
A small number of zircon analyses from COL20D have been
interpreted as metamorphic, as CL images show they target
dark zircon rims and homogenous areas which cross cut original
oscillatory zoning. A mean weighted average of 5 interpreted meta-
morphic zircon analyses record metamorphism at 1695 ± 18 Ma
(MSWD = 0.45). In addition, another two zircon analyses, Z33
and Z52, target areas of oscillatory zoning yet provide ages of
1707 ± 21 Ma and 1712 ± 20 Ma. These ages are much younger than
the next youngest group of detrital zircon grains (ca 1760 Ma).
Given the evidence for high-grade metamorphism in the region
at ∼1700–1690 Ma, including within this sample, it is not possible
for us to determine if these ages are reliable or suffer from ancient
Pb-loss. Hence we assume the older age (1760 Ma) to represent
the maximum deposition age so as to avoid incorrectly assigning a
young depositional age which would have significant implications
for the tectonic depositional environment of this sample.
4.4. Zircon Hf isotopic results
Zircon Hf isotopic results are shown in Supplementary Table 3
and Fig. 9. Data were obtained from four metasedimentary samples;
COL20D, BAC41, BAC18 and TAL4. Together, the 1780–1700 Ma zir-
cons from the Fowler Domain metasedimentary samples have a
broad range of initial εHf values between −6 and +6.
However, there are slight variations between samples. Initial
isotopic εHf compositions for the bulk of detrital zircons aged
between 1780 and 1700 Ma range from +2 to −2 for BAC18 and +3
to −2 for TAL4. In addition, TAL4 has three 1720–1650 Ma grains
with initial εHf values between +6 and +8, and BAC18 has one very
evolved 1760 Ma aged grain with an εHf value of −16. Initial εHf
compositions for samples BAC41 and COL20D are similar but have
slightly more evolved ranges of εHf units of +2 to −6 and +2 to −5
respectively for 1780–1700 Ma detrital zircons. COL20D contains a
cluster of zircons with ages between 1980 and 1950 Ma which have
initial Hf isotopic compositions of between +3 and +5. Zircon grains
older than 2100 Ma from COL20D and TAL 4 have crustal model ages
older than 3000 Ma.
4.5. U–Pb monazite geochronology
In order to better constrain the minimum depositional ages
of the metasedimentary protoliths and to improve existing con-
straints on the timing of metamorphism in the western Gawler
Craton, monazites from four metasedimentary samples were
dated; BAC18, BAC41, TAL20, and COL20D. Monazite grains have
been interpreted as metamorphic as all samples contain upper
amphibolite grade mineral assemblages (Thomas et al., 2008) and
the grains occupy a matrix textural setting. Monazite ages are sum-
marised in Table 4, data are displayed in Supplementary Table 2 and
weighted mean 207Pb/206Pb age plots are shown in Fig. 10.
Back-scatter electron (BSE) images show that monazites from
the four samples have two irregularly shaped compositional zones
(Fig. 11). While there is some range in the ages of monazites, no
correlation was found between U–Pb age and compositional zoning
for any of the samples analysed.
Twenty monazites from COL20D, within the Colona Block, gave
a weighted mean 207Pb/206Pb age of 1690 ± 9 Ma. This is within
error of the metamorphic zircon age of 1704 ± 17 Ma. Within the
Barton Block, 30 monazites from sample BAC 41, gave a weighted
mean 207Pb/206Pb age of 1665 ± 7 Ma. TAL 20 has a weighted mean207Pb/206Pb age of 1673 ± 9 Ma from 20 monazites. Sample BAC
18 has a weighted mean 207Pb/206Pb age of 1696 ± 13 Ma from 17
monazites.
5. Discussion
5.1. Depositional age constraints
Due to young cover sequences blanketing the western Gawler
Craton, relationships between different rock types in the Fowler
Domain are rarely exposed. Additionally, the spatial extent of units
is largely unknown, because of the wide spacing of drill holes and
the presence of intervening crustal-scale faults (Fig. 2; Thomas
et al., 2008; Stewart et al., 2009). There is no direct information
to prove the metasedimentary rocks are part of the same sedimen-
tary succession. However, because the data are similar they can be
interpreted as representative of depositional ages over a broad area,
and as having a shared source. Taken together, the U–Pb zircon data
from metasedimentary rocks in the Fowler Domain suggest that
maximum depositional ages range between ca 1760 and 1700 Ma.
As these samples were collected from limited amounts of drill
core, minimum depositional ages could not easily be obtained by
dating crosscutting igneous intrusives. Monazite ages can be used
to constrain the minimum depositional ages for metasedimentary
rocks if they record the timing of metamorphism. The samples from
which monazites were obtained contain metapelitic assemblages
that formed between 500 and 700 ◦C and 4–9 kbar (Thomas et al.,
2008). Since detrital monazite is uncommon in high grade meta-
morphic rocks (Copeland et al., 1988), monazite ages from these
rocks are interpreted to reflect the timing of metamorphism.
Metamorphic monazite ages and hence minimum depositional
ages for metasedimentary rocks from the Fowler Domain range
between ca 1695 and 1665 Ma. These monazite U–Pb age con-
straints are significantly older than the EMPA monazite ages
obtained by Thomas et al. (2008) from the Fowler Domain which
ranged from 1650 to 1600 Ma. The source of this discrepancy
appears to be analytical in nature. In their study, Thomas et al.
(2008) do not appear to have adequately accounted for spectral
overlaps between the Th Mg peak on U Mb and U Mz2 on Pb Mb
in their monazite analyses. This conclusion is based upon the spec-
tral analysis of Dutch et al. (2010) for monazite analysis within
the same facility using the same operating conditions. For the
analysed monazite compositions, this resulted in ages that were
slightly too young. Reprocessing of the original data of Thomas
et al. (2008) using the spectral overlaps determined by Dutch et al.
(2010), results in more consistency between the existing EMPA data
and the LA-ICPMS monazite ages obtained in this study (Table 5).
Nevertheless, given that the EMPA ages can be affected by slight
discordance in the monazite populations, we suggest that the LA-
ICPMS monazite ages are more reliable than the EMPA ages.
-62-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 5. Chondrite-normalised REE plots of Fowler Domain metasedimentary rocks
overlaying patterns from metasedimentary rocks of the northern Gawler Craton
(Payne et al., 2006), the Mt Woods Domain (Chalmers, 2007), the lower Willyama
Supergroup of the Curnamona Province (Barovich and Hand, 2008) and granites of
the Arunta Region (Zhao and McCulloch, 1995). PAAS: the post-Archean Australian
Shale and normalising values after Taylor and McLennan (1985).
Fig. 6. εNd vs. time for Fowler Domain metasedimentary rocks compared with
(meta)sedimentary rocks of the lower Willyama Supergroup (Barovich and Hand,
2008), the northern Gawler Craton (Payne et al., 2006), the Mt Woods Domain (this
study) and the Arunta Region (Zhao and McCulloch, 1995). Data for average Archean
Gawler Craton are from Swain et al. (2005a), Fanning et al. (2007), Payne et al. (2010)
and Fraser et al. (2010). Data for average Palaeoproterozoic Gawler Craton >1750 Ma
are from Howard et al. (2009) and Schaefer (1998). Average Gawler Craton fields
have margins of ±1 standard deviation.
Very little is known about the basement rocks to the metasedi-
mentary cover sequences in the Gawler Craton. However, a granite
which intrudes around 1710 Ma (Howard, in preparation) has εNd
values of −2.1 suggesting that basement may be comparatively
juvenile with respect to the average Gawler Craton. There are other
granites whose isotopic character is unknown but could potentially
provide information on basement to the cover sequences in the
Fowler Domain (Teasdale, 1997). In the Colona Block detrital zir-
cons range in age down to ca 1730 Ma. This is similar to the age
of a weakly to moderately deformed gabbro dated from drill hole
COLDDH43 (1727 ± 8 Ma; Fanning et al., 2007). Based on available
age constraints it is not possible to determine if the emplacement
of this metagabbro predates or postdates deposition.
The paucity of outcrop, intensity of deformation and lack of
knowledge of the basement to the Fowler Domain make it difficult
to have any firm idea about the tectonic setting of sedimenta-
tion.
5.2. Source characteristics of the Fowler Domain
metasedimentary rocks
Geochemically, the metasedimentary units of the Fowler
Domain are interpreted to be pelitic in composition, with some
of the more silica rich samples considered psammitic. REE plots
show that these samples are significantly enriched compared to
PAAS, particularly in the LREEs, while slightly depleted in HREEs
compared to PAAS in some samples. Very high Th/Sc ratios in the
majority of samples suggest that the provenance to the metasedi-
mentary rocks consisted of enriched felsic upper crust (McLennan
et al., 2003; Taylor and McLennan, 1995).
U–Pb detrital zircon data from two samples, BAC18 and TAL4,
are dominated by single peaks with individual zircon ages ranging
from 1770 to 1700 Ma. The mineral assemblages in these samples
have a pelitic character (Table 1) and major element compositions
also suggest a sedimentary protolith. The presence of restricted
zircon populations suggests comparatively local derivation in a
sedimentary system isolated from source regions >1800 Ma old.
Unfortunately, other evidence for a proximal source region, such
-63-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 7. Age probability density plots for detrital zircons from metasedimentary rocks
of the Fowler Domain. Dark grey shaded field represents data with less than 10%
discordance. Light grey shaded fields represent all data. Maximum depositional ages
are displayed.
Fig. 8. CL images of representative zircon grains from the Fowler Domain. (a) Z34,
from sample COL20D, a typical detrital zircon and (b) Z58, from sample COL20D, an
interpreted metamorphic analysis.
as coarser grain size or lithic fragments, is not preserved due to the
intensity of recrystallisation. However, the restricted populations
in these samples could also be explained by the limited number of
zircons analysed, as the spectra do not necessarily represent statis-
tically robust detrital zircon populations (Andersen, 2005). Samples
COL20D, BAC23 and BAC41 record older detrital components, with
minor peaks up to 3130 Ma in age. This suggests that additional
source regions contributed Paleoproterozoic and Archean material.
The metasedimentary rocks of the Fowler Domain record
εNd(1700 Ma) values of between −4.3 and −3.8 including COL20D
and BAC23 which have older detrital zircon ages. This range is
more juvenile than the average Archean and early Paleoproterozoic
(>2450 Ma) Gawler Craton with εNd(1700 Ma) value of approximately
−12 (Fanning et al., 2007; Fraser et al., 2010; Howard et al., 2009;
Payne et al., 2010; Swain et al., 2005a). However, metasedimen-
tary rocks from the Fowler Domain are similar but slightly more
juvenile compared with the average Paleoproterozoic (>1750 Ma)
Gawler Craton which has εNd(1700 Ma) value of approximately −5
(Howard et al., 2009; Scrimgeour et al., 2001). Given the presence
of Archean zircon ages in some of the metasedimentary samples,
it seems likely that the Archean Gawler Craton contributed at least
a small portion of material to the basin system. However, if the
metasedimentary rocks were derived solely from the Archean and
Paleoproterozoic Gawler Craton, we would expect them to have
initial isotopic compositions between −5 and −12. Therefore the
less negative initial εNd values of the metasedimentary rocks of
the Fowler Domain suggest additional input from a more juvenile
source region.
Within the 1780–1700 Ma time frame, Hf isotopic data from
the Fowler Domain are isotopically similar to modern day sed-
iment sampled from the Gawler Craton in not including the
Fowler Domain in a Terranechron study (Belousova et al., 2009;
Figs. 8 and 12). The crustal model ages calculated for 1780–1700 Ma
detrital zircons from the Fowler Domain metasedimentary rocks
range from 2.20 to 2.84 Ga. These model ages are significantly
younger than model ages from >1900 Ma aged zircons eroding
from the Gawler Craton (Belousova et al., 2009). Assuming that
the Gawler Craton Terranechron reflects erosion from the Gawler
Craton, this suggests that the 1780–1700 Ma zircons are evidence
of a younger or more juvenile contribution. However, Hf isotopic
data from the 1700–1900 Ma zircon grains from the Gawler Craton
Terranechron have identical model ages to those from the Fowler
Domain (Belousova et al., 2009), suggesting that juvenile input to
the Gawler Craton occurred during this time interval.
Zircons grains analysed >2100 Ma have crustal model ages of
greater than 3.0 Ga suggesting that metasedimentary rocks of the
Fowler Domain may have been derived from a small portion of
Mesoarchean Gawler Craton.
-64-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 9. εHf values plotted against 207Pb/206Pb ages for individual zircon grains from four metasedimentary samples from the Fowler Domain. The Gawler Craton data are from
Belousova et al. (2009). Discordant grains (>10%) have been omitted. Inset is a probability density plot of εHf values for zircons from the 1700–1750 Ma cluster. The range of
crustal model ages is indicated.
5.3. Correlations with other basin systems within the southern
Australian Proterozoic
There are a series of Paleoproterozoic basin systems in the
Gawler Craton with similar depositional age constraints and detri-
tal zircon spectra to the Fowler Domain metasedimentary rocks
(Fig. 13; Table 6). These are the ca 1760–1740 Ma Wallaroo Group
(Fanning et al., 1988; Jagodzinski, 2005), ca 1740 Ma metased-
imentary rocks from the Mt Woods Domain (Chalmers, 2007;
Jagodzinski et al., 2007) and ca 1740 Ma metasedimentary rocks of
the northern Gawler Craton (Payne et al., 2006). Previous authors
have suggested that the similarity in the timing of deposition of
these (meta)sedimentary units indicate that they could be part of
a widespread Paleoproterozoic basin system (Hand et al., 2007;
Payne et al., 2006) suggesting the presence of a coherent older base-
ment. The depositional age constraints on the metasedimentary
units from the Fowler Domain suggest that they could also belong
to this large scale basin system. The Nd isotopic data from the Mt
Woods Domain was obtained as an additional part of this study and
is shown in Appendix 1. Appendix 1 also summarises all the avail-
able Sm–Nd isotopic data from the southern Australian Proterozoic
ca 1760–1700 Ma basins.
Previous work on metasedimentary rocks from drill core within
the northern Gawler Craton (Payne et al., 2006), show similarities in
provenance to the Fowler Domain (Table 6, Fig. 14). The metasedi-
mentary rocks from the northern Gawler Craton record a maximum
depositional age of ca 1740 Ma, calculated by the youngest group
of detrital zircons and a minimum depositional age of ca 1720 Ma
based on the ages of metamorphic zircons and monazite (Payne
et al., 2006, 2008). Major detrital zircon populations are recorded at
ca 1730–1750, 1750–1780 and 1800–1820 Ma (Payne et al., 2006),
which are similar to the range of zircon ages found in the Fowler
Domain. Nd isotopic data are almost identical to the Fowler Domain
samples, with εNd(1700 Ma) values ranging from −6 to −3 (Payne
et al., 2006). Geochemically, the REE patterns for metasedimentary
rocks from the northern Gawler Craton are similar with slightly
more HREE enrichment compared with those from the Fowler
Domain (Payne et al., 2006). Both appear too enriched to be derived
from the >1800 Ma components of the Gawler Craton (Swain et al.,
2005a).
In the Mt Woods Domain in the central eastern Gawler Cra-
ton (Fig. 1) metasedimentary rocks record maximum depositional
ages of ca 1750 Ma based on the youngest group of detrital zir-
cons in three samples (Chalmers, 2007; Jagodzinski et al., 2007).
Minimum depositional ages of 1691 ± 25 Ma are constrained by
the intrusive Engenina Adamellite (Chalmers, 2007). Therefore, the
Mt Woods metasedimentary rocks show similar depositional tim-
ing to those from the Fowler Domain and the northern Gawler
Craton. Detrital zircon histograms are also very similar to those
from the Fowler Domain and northern Gawler Craton, and are
dominated by one major peak at ca 1750 Ma, with some minor
inheritance of 1850 Ma zircon grains, and a lack of >1850 Ma grains
(Chalmers, 2007; Jagodzinski et al., 2007). The Nd isotopic com-
positions from the metasedimentary rocks (εNd(1700 Ma) −2.1 to
−4.9) are similar to the values from the northern Gawler Craton
and the Fowler Domain. REE patterns from the metasedimentary
rocks of the Mt Woods Domain (Fig. 4) are a good match with
the northern Gawler Craton, and are similar but slightly more
Table 5Recalculated EMPA monazite ages from Thomas et al. (2008) and LA-ICPMS monazite ages obtained in this study.
Drill hole Depth (m) Easting Northing Rock type Mineral assemblage Age (Ma) Method Reference
BAC23 EOH 250347 6573841 Protomylonite gt-bi-sill 1666 ± 17 EMPA Thomas et al. (2008) a
BAC33 EOH 253552 6573288 Mylonite gt-bi-sill 1635 ± 19 EMPA Thomas et al. (2008) a
COL20D 44.0 782283 6536364 Metapelite gt-bi-mus-plag-ilm 1683 ± 12 EMPA Thomas et al. (2008) a
COL20D 46.2 782283 6536364 Metapelite gt-bi-mus-plag 1649 ± 14 EMPA Thomas et al. (2008) a
COL20D 47.0 782283 6536364 Metapelite gt-bi-mus-plag 1688 ± 13 EMPA Thomas et al. (2008) a
NDR1 41.0 238062 6478212 Metapelite gt-bi-plag 1505 ± 14 EMPA Thomas et al. (2008) a
NDR5 45.0 240516 6474390 Pelitic gneiss gt-bi-sill-plag-kf-ilm 1593 ± 15 EMPA Thomas et al. (2008) a
COL20D 46.6–47.5 782283 6536364 Metapelite gt-bi-mus-plag-ilm 1690 ± 9 LA-ICP-MS This study
BAC18 EOH 248614 6574437 Metapelite qtz-bi-kspar-gt-sill-plg 1696 ± 10 LA-ICP-MS This study
BAC41 EOH 255670 6573107 Metapelite plg-bi-qtz-sill-gt-ilm 1664 ± 7 LA-ICP-MS This study
TAL20 57.0–57.5 247028 6560272 Metapelite qtz-kspar-plg-bi-sill-gt 1673 ± 9 LA-ICP-MS This study
a Reprocessed using the spectral overlaps determined by Dutch et al. (2010).
-65-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 10. Concordia and weighted average plots for monazites from metasedimentary rock samples from the Fowler Domain.
enriched in HREEs when compared with REE patterns of the Fowler
Domain.
The Wallaroo Group in the south eastern Gawler Craton
(Fig. 1) contains a range of Paleoproterozoic metasedimentary and
metavolcanic units (Conor, 1995; Cowley et al., 2003). The Wan-
dearah Formation has a maximum depositional age of 1762 ± 7 Ma
based on the youngest detrital zircon peak with inheritance up
to 3320 Ma (Jagodzinski, 2005). The timing of deposition for the
Wandearah Formation is also constrained by intercalated felsic
volcanics with ages of 1763 ± 14 Ma and 1750 ± 7 Ma (Fanning in
Conor, 1995), making the Wallaroo Group similar to COL20D but
slightly older than the other Fowler Domain metasedimentary
rocks. Whole rock εNd(1700 Ma) values vary widely from +1.4 to −6.6
between the members of the Wandearah Formation (Huffadine,
1993; Simpson, 1994), suggesting that sediment input was derived
from isotopically varied source regions. Isotopic Hf zircon data
for the Wandearah Formation yielded εHf(ca 1750 Ma) values rang-
ing from −5 to 0 (Belousova et al., 2009), which match with the
ca 1750 Ma aged zircons from the Fowler Domain. This suggests
that zircons (and sediment) of similar age and isotopic compo-
sition were being deposited at least at the present day eastern
and western edges of the Gawler Craton, but potentially craton-
wide, between 1760–1700 Ma. A fine-bedded tuffaceous siltstone
of the Mona Volcanics Member, also belonging to the Wallaroo
-66-
Chapter 3 Provenance and depositi onal ti ming, western Gawler CratonTa
ble
6Su
mm
ary
tab
leco
mp
ari
ng
sou
rce
chara
cteri
stic
sfo
rP
ala
eo
pro
tero
zo
icB
asi
ns
syst
em
sfr
om
the
Gaw
ler
Cra
ton
an
dth
eC
urn
am
on
aP
rov
ince
.
Fo
wle
rD
om
ain
Naw
aD
om
ain
Mt
Wo
od
sD
om
ain
Wall
aro
oG
rou
pLo
wer
Wil
lyam
a
Su
perg
rou
p
Dep
osi
tio
nal
tim
ing
17
60
–1
70
0M
aa
17
40
–1
72
0M
ab
17
50
–1
69
0M
ac
,dca
17
60
Ma
e1
71
5–
16
70
Ma
j,k
Detr
ital
zir
con
peak
s1
70
0–
17
80
,18
30
,19
50
,
very
min
or
inh
eri
tan
ceto
31
00
Ma
a
17
30
–1
75
0,1
75
0–
17
80
an
d1
80
0–
18
20
Ma
b
17
10
–1
79
0,w
ith
min
or
peak
18
50
Ma
c,d
17
15
–1
81
0,1
85
0,v
ery
min
or
peak
sca
20
00
an
d
25
00
–2
60
0M
ae
,f
16
70
–1
71
0,1
72
0–
18
90
,
20
50
,23
00
,25
00
–2
70
0
an
d3
00
0M
aj,
k
Wh
ole
rock
Nd
iso
top
icat
17
00
Ma
−3.8
to−4
.3a
−3to
−6b
−2.1
to−4
.9a
+1
.4to
−6.6
g,h
−3to
−8l
ε Hf
zir
con
valu
es
at
ca1
71
0–
17
80
Ma
+2
to−6
aN
oav
ail
ab
led
ata
No
av
ail
ab
led
ata
0to
−5i
No
av
ail
ab
led
ata
RE
Ep
att
ern
sco
mp
are
dto
Fo
wle
rD
om
ain
Sim
ilar
bu
tsl
igh
tly
mo
re
en
rich
ed
inH
RE
Esb
Sim
ilar
bu
tsl
igh
tly
mo
re
en
rich
ed
inH
RE
Esd
No
av
ail
ab
led
ata
Sim
ilar
RE
Ep
att
ern
sl
aT
his
stu
dy
.b
Pay
ne
et
al.
(20
06
).c
Jag
od
zin
ski
et
al.
(20
07
).d
Ch
alm
ers
(20
07
).e
Jag
od
zin
ski
(20
05
).f
Fan
nin
get
al.
(20
07
).g
Hu
ffad
ine
(19
93
).h
Sim
pso
n(1
99
4).
iB
elo
uso
va
et
al.
(20
09
).j
Pag
eet
al.
(20
05
a).
kP
ag
eet
al.
(20
05
b).
lB
aro
vic
han
dH
an
d(2
00
8).
Fig. 11. BSE images of representative monazites from samples BAC41, COL20D and
TAL20.
Group, contains a bimodal zircon distribution with populations at
1740 ± 16 Ma and 1790 ± 15 Ma (Fanning et al., 2007). The younger
age is thought to represent the timing of volcanic eruption, and
therefore the timing of deposition, while the older peak represents
inheritance (Fanning et al., 2007). The inferred depositional age is
similar to the inferred range in the northern Gawler Craton.
The Moonabie Formation from the eastern Gawler Craton has a
maximum depositional age of 1756 ± 8 Ma based on the dominant
unimodal detrital zircon peak (Jagodzinski, 2005). Isotopically this
unit has εNd(1700 Ma) of −7.1 (Simpson, 1994), which is more evolved
than the Fowler Domain metasedimentary rocks.
Within the Gawler Craton it is clear that there was widespread
sedimentation between ca 1760 and 1700 Ma. The timing of the
sedimentation initially predates the Kimban Orogeny (Chalmers,
2007; Fanning et al., 2007; Jagodzinski, 2005; Jagodzinski et al.,
2007; Payne et al., 2006). In the eastern Gawler Craton the Kimban
Orogeny was responsible for low to medium pressure greenschist
to granulite facies metamorphism between 1720 and 1690 Ma
(Dutch et al., 2010). This range of ages is similar to the metamorphic
-67-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Fig. 12. εHf values plotted against 207Pb/206Pb ages for individual zircon grains from the Fowler Domain compared with modern sediment samples from different regions of
the Gawler Craton (Belousova et al., 2009). Solid geology Gawler Craton map is modified after Fairclough et al. (2003). The shaded area is the Fowler Domain.
ages in the northern Gawler Craton (Payne et al., 2008). However, it
appears that both the timing of sedimentation and also deformation
in the Fowler Domain was slightly younger, with sedimentation
until ca 1700 Ma and metamorphism as late as ca 1660 Ma.
External to the Gawler Craton, but within the South Australian
Craton (Fig. 1), the metasedimentary Willyama Supergroup of
the Palaeo-Mesoproterozoic Curnamona Province is another basin
system which could potentially correlate with the Gawler Cra-
ton metasedimentary rocks. The timing of deposition of units
from the lower Willyama Supergroup is ca 1715–1670 Ma (Page
et al., 2005a,b) which encompasses the interval of deposition of
sequences in the Fowler Domain. Major detrital zircon peaks occur
at 1690 and 1790 Ma, and there is a large array of inherited grains
up to ca 3000 Ma (Page et al., 2005b). The basins represented by
the lower Willyama Supergroup probably sourced sediment from
a variety of terranes of various ages compared with the Fowler
Domain. Sm–Nd isotopic data from the lower Willyama Super-
group are similar but display a wider range compared to the Fowler
Domain (Fig. 5) with εNd(1700 Ma) values ranging from ca −3 to
−8, and averaging −5 ± 1 (Barovich and Hand, 2008). This is only
slightly more evolved than the Fowler Domain metasedimentary
samples, which, coupled with the abundance of older zircons (Page
Fig. 13. Detrital zircon age histograms and isotopic whole rock εNd values from Paleoproterozoic basin systems within the Gawler Craton and Curnamona Province of similar
depositional timing to the Fowler Domain. Northern Gawler Craton data from Payne et al. (2006); Fowler Domain data from this study; Mt Woods Domain U–Pb zircon data
from Chalmers (2007) and Jagodzinski et al. (2007), Nd isotopic data from this study; Wallaroo Group U–Pb zircon data from Jagodzinski (2005) and Fanning et al. (2007),
Nd isotopic data from Huffadine (1993) and Simpson (1994); Willyama Supergroup U–Pb zircon data from Page et al. (2005a,b), Nd isotopic data from Barovich and Hand
(2008).
-68-
Chapter 3 Provenance and deposi� onal � ming, western Gawler Craton
Fig. 14. Reconstruction models for Paleoproterozoic Australia. (a) Dawson et al. (2002) positions the northern Gawler Craton as the indentor to the Yilgarn Craton as it
collides with the Gawler Craton deforming the Fowler Domain. (b) Wade et al. (2006) suggests the Gawler Craton and North Australian join around 1590–1550 Ma. (c) Betts
and Giles (2006) propose that the Gawler Craton accreted in three stages to the North Australian Craton via a north dipping subduction zone on the southern margin of the
North Australian Craton. (d) Payne et al. (2009) presents a model which places the entire Gawler Craton and Curnamona Province adjacent to the North Australian for the
duration of the Proterozoic.
et al., 2005a,b), suggests some input from older and more isotopi-
cally evolved source regions. Geochemically, REE patterns from the
lower Willyama Supergroup are unusually enriched (Barovich and
Hand, 2008), and are a good match with the patterns from the
metasedimentary rocks of the Fowler Domain (Fig. 4).
We have established that southern Australian Paleoprotero-
zoic basin systems within the Gawler Craton and the Curnamona
Province share similarities in timing of deposition. REE patterns
of the basins are enriched and remarkably similar. In particu-
lar, REE patterns from metasedimentary rocks from the northern
Gawler Craton and Mt Woods Domains are almost identical. The
Nd isotopic character of the basin systems is also similar, however
(meta)sedimentary rocks with a wider range of inherited zircon
ages such as the Wallaroo Group and the Lower Willyama Super-
group (presently the easterly-most basins) tend to have a slightly
more evolved range of initial εNd values. This suggests that the east-
erly basins may have received a contribution of older and more
evolved material than the northwestern basins. Given the overall
NOTE: This figure is included on page 68 of the print copy of the thesis held in the University of Adelaide Library.
NOTE: This figure is included on page 68 of the print copy of the thesis held in the University of Adelaide Library.
-69-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
similarities in source characteristics, it is likely that these Paleopro-
terozoic basin systems had a shared provenance, and derived some
material from common source regions.
Given the locations of these Paleoproterozoic basin systems, the
first source region to consider would be the Archean to Paleopro-
terozoic Mawson Continent which includes the Gawler Craton and
the Adelie Craton in Antarctica (Payne et al., 2009). The appear-
ance of a small number of ca 1850 Ma detrital zircons in each of
the basin systems (northern Gawler Craton, Mt Woods Domain,
Wallaroo Group, Lower Willyama Supergroup and Fowler Domain;
Fig. 13 and Table 6) suggests that the voluminous ca 1850 Ma Don-
ington Suite located in the eastern Gawler Craton may have been
exposed between 1760 and 1700 Ma. This implies that >1750 Ma
components of the Gawler Craton may have supplied detritus to
these sedimentary basin systems. In addition, >3000 Ma crustal
model ages for detrital zircons aged >2100 Ma suggests that a small
portion of material may have been derived from the Mesoarchean
Gawler Craton. However, the general lack of Gawler Craton zir-
con forming time lines >1850 Ma in detrital zircon histograms
(2520 Ma, 2470–2450, 2000 Ma; Hand et al., 2007; Howard et al.,
2009; Belousova et al., 2009), suggests that the Gawler Craton was
not a major source of material to these 1760–1700 Ma basin sys-
tems. Additionally, detritus derived from a mixture of the currently
exposed Paleoproterozoic and Archean rocks from the Gawler Cra-
ton would be isotopically too evolved (Fanning et al., 2007; Fraser
et al., 2010; Howard et al., 2009; Payne et al., 2010; Schaefer, 1998;
Swain et al., 2005a) to be the principle source for the relatively less
evolved Paleoproterozoic basin systems (Fig. 6). For these reasons,
we suggest that the 1760–1700 Ma sequences in the southern Aus-
tralian Proterozoic received additional more juvenile material from
source regions beyond the Gawler Craton.
Payne et al. (2006) had considered a Laurentian source region
for the metasedimentary rocks of the northern Gawler Craton, but
this was excluded as suitably aged rocks were much too juvenile.
Likewise, Barovich and Hand (2008) considered the Mt Isa Inlier
of northern Australia as a potential source region for the lower
Willyama Supergroup; however trace and rare earth element abun-
dances were PAAS like and not enriched. Payne et al. (2006) and
Barovich and Hand (2008) therefore concluded that the most likely
source region to the lower Willyama Supergroup and the northern
Gawler Craton metasedimentary rocks was the Aileron Province
of the Arunta Region (Fig. 1) in the southern part of the North
Australian Craton.
Major zircon forming time lines in the Aileron Province occur
at 1820–1800 Ma, 1780–1750 Ma, and 1735–1690 Ma (Black and
Shaw, 1992; Claoueı̌-Long et al., 2008; Claoué-Long and Hoatson,
2005; Collins and Shaw, 1995; Collins and Williams, 1995;
Maidment et al., 2005; Scrimgeour et al., 2001; Wade et al.,
2008; Zhao and Bennett, 1995; Zhao and Cooper, 1992; Zhao and
McCulloch, 1995), which match many of the dominant detrital
zircon peaks from the 1760–1700 Ma basin systems of the South
Australian Craton. The Arunta Region also records metamorphism
during the Strangways Orogeny (1730–1690 Ma; Maidment et al.,
2005; Claoué-Long et al., 2008), which is similar but slightly older
than metamorphism in the Fowler Domain, but matches well with
the timing of metamorphism in the northern Gawler Craton (Payne
et al., 2008).
Geochemically, the 1820–1700 Ma magmatic rocks in the
Arunta Region are moderately to highly enriched in REE (Fig. 5;
Sun et al., 1995; Zhao and McCulloch, 1995; Budd et al., 2001).
Isotopically, 1770–1710 Ma magmatic rocks of the Arunta Region
provide initial εNd values within the range −0.2 to −4.9 and aver-
age εNd value of −2 ± 1.5 at 1700 Ma (Fig. 6; Zhao and McCulloch,
1995). This is comparatively more juvenile than the Paleoprotero-
zoic basin systems of the South Australian Craton as well as the
average Archean and Paleoproterozoic Gawler Craton. However,
a mixture of juvenile detritus from the Arunta Region combined
with more evolved Archean and Palaeoproterozoic Gawler Craton
material would result in the range of isotopic compositions similar
to what is recorded by the Paleoproterozoic basin systems of the
South Australian Craton.
5.4. Provenance implications for reconstruction models of
Proterozoic Australia
The notion that the Arunta Region may have been a domi-
nant source for Paleoproterozoic sedimentary basins of the Gawler
Craton and the Curnamona Province has implications for at least
four recently published Paleoproterozoic reconstruction models for
southern and central Australia; Dawson et al. (2002), Wade et al.
(2006), Betts and Giles (2006) and Payne et al. (2009).
The reconstruction model by Dawson et al. (2002) is based on a
provenance connection between a sedimentary succession on the
Yilgarn Craton with the most likely source being the Gawler Craton.
This model proposes that the Fowler Domain and the Karari Shear
Zone (Fig. 1) record the collision between the Yilgarn Craton includ-
ing the present day northern Gawler Craton and a Gawler-Pilbara
continent at ca 1750–1700 Ma (Fig. 14a). Our results highlight sev-
eral problems with this model. Firstly, it places the northern Gawler
Craton on the Yilgarn micro-continent, separating it from the other
basin systems and from the Arunta Province until 1750–1700 Ma.
This does not allow much time for sediment to be transported
from the North Australian Craton and deposited before metamor-
phism at 1720 Ma (Payne et al., 2006). Secondly, if the northern
Gawler Craton were to have been positioned at the leading edge
of a continental plate as it collided with the Gawler Craton, it is
likely that geochemistry and whole rock Nd isotopes would have
detected some component of juvenile arc magmatism as a source.
Instead, geochemistry of the northern Gawler Craton metasedi-
mentary rocks point to an enriched intracrustal source for the
sediments, similar to the other time correlative basin sequences
in southern Australia (Payne et al., 2006).
Based on the inferred existence of arc-like magmatism at ca
1590–1550 Ma in the Musgrave Block, positioned between the
North Australian Craton and the Gawler Craton, Wade et al. (2006)
suggested the presence of an active margin between the two
cratons (Fig. 14b). This positions the northern Gawler Craton,
Fowler, and Mt Woods Domains and Wallaroo Groups together
on the Mawson Continent, while the Willyama Supergroup is
positioned on a separate Curnamona Province micro-plate at
around 1590–1550 Ma. This model does not allow a mechanism
for sediment transport from the North Australian Craton to the
Paleoproterozoic basin systems at around 1760–1710 Ma without
a complicated rifting phase between 1710 and 1590 Ma.
Betts and Giles (2006) build on previous models (Betts et al.,
2002; Giles et al., 2002, 2004), and propose a north dipping accre-
tion zone on the southern margin of the North Australian Craton
(Fig. 14c). Attached to the North Australian Craton are those basins
which are located to the present day east of the Kalinjala Shear Zone,
located in the south eastern Gawler Craton (Fig. 1), and include the
Willyama Supergroup and the Wallaroo Group. The proto-Gawler
Craton, including its Archean components, is thought to have been
accreted between 1740 and 1690 Ma to the North Australian Craton
aligning the Kimban Orogeny with the Strangways Orogeny of the
Arunta Province. A ribbon of crust including the Fowler and north-
ern Gawler Craton are then accreted alongside the Archean Christie
Domain between 1690 and 1650 Ma (Fig. 14c).
Betts and Giles (2006) suggest that the Archean Mulgathing
Complex (Christie Domain), is accreted to the crust containing
the Archean Sleafordian Complex during the Paleoproterozoic at
ca 1690 Ma, even though they have been shown to share identi-
cal tectonic and sedimentary histories (Payne et al., 2009; Swain
-70-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
et al., 2005a). Similarly this model also divides the group of simi-
larly sourced sedimentary basins across different micro-continents
at the time of basin formation. While the model does allow
a connection between the Willyama Supergroup and Wallaroo
Group to a likely source, the Arunta Region, during the time
of deposition, other basins such as the northern Gawler Craton,
the Fowler and the Mt Woods Domains are isolated from this
source.
If the reconstruction model of Betts and Giles (2006) is cor-
rect it means that the Fowler Domain and northern Gawler Craton
metasedimentary rocks must have been entirely locally sourced
from the northern Gawler Craton/Fowler/Christie Domain micro-
continent with no contribution from the Gawler Craton or the North
Australian Craton. This is very difficult to account for as there are
no known magmatic sources for the 1740–1780 Ma detrital zircon
grains within those three domains. If derived from the micro-
continent alone, we would expect the Fowler Domain and northern
Gawler Craton metasedimentary rocks to contain a large contribu-
tion of inherited material from the 2560–2450 Ma Christie Domain.
However, this is not the case as there are no zircons >2450 Ma in
the metasedimentary rocks of the northern Gawler Craton (Payne
et al., 2006) and <5% from metasedimentary rocks of the Fowler
Domain (this study). Metasedimentary rocks from the northern
Gawler Craton and the Fowler Domain (εNd(1700 Ma) −3 to −6)
show little contribution from the evolved Archean Christie Domain
(εNd(1700 Ma) of −11.7 to −12.3; Swain et al., 2005a,b). Another
requirement which the Betts and Giles (2006) model does not sat-
isfy are the geochemical constraints from the northern Gawler
Craton and the Fowler Domain that suggest that the sediments
were derived from an intracratonic source. It therefore appears
unlikely that the northern Gawler Craton and the Fowler Domain
metasedimentary rocks were derived from a northern Gawler Cra-
ton/Fowler/Christie Domain micro-continent.
A more favourable reconstruction model using recent con-
straints was proposed by Payne et al. (2009), which recognises the
similarities in time lines of events between the North Australian
Craton, Curnamona Province and Gawler Craton and consequently
places them adjacent for the duration of the Paleoproterozoic
(Fig. 14d). This model places the Paleoproterozoic basins of the
South Australian Craton contiguous to one another in an intracra-
tonic position satisfying geochemical constraints. It also positions
the Arunta Region adjacent to the South Australian Craton at
the time of deposition of the basin systems thereby providing a
source of isotopically mixed material and detrital zircons with
1720–1780 Ma ages that match those found in samples studied
from the basin systems.
6. Conclusions
1. Detrital zircon and monazite data provide maximum depo-
sitional ages of between 1710 and 1760 Ma and minimum
depositional ages of between 1690 and 1670 Ma for the Fowler
Domain metasedimentary rocks.
2. Paleoproterozoic basins from the Gawler Craton and the Curna-
mona Province, including the Fowler and Mt Woods Domains,
the northern Gawler Craton, the Wallaroo Group and the lower
Willyama Supergroup show similar geochemical and Nd iso-
tope source characteristics supporting an evolved and enriched
intracrustal source region with detrital zircon histograms dom-
inated by 1790–1710 Ma grains that are best interpreted as
sourced from the Arunta Region of the North Australian Craton.
3. Implications for an Arunta Region source to the Paleoproterozoic
basin systems of the Gawler Craton and Curnamona Province
require a connection between the South Australian Craton and
the North Australian Craton by at least 1760–1710 Ma, implying
that many existing reconstruction models for Paleoproterozoic
Australia require modification.
Acknowledgements
We would like to acknowledge discussions with Anthony Reid,
Mike Szpunar, Rian Dutch and Ailsa Woodhouse (Geological Sur-
vey, Primary Industries and Resources South Australia) and Kathryn
Cutts (University of Adelaide). We are grateful to Benjamin Wade
and Angus Netting of Adelaide Microscopy for invaluable assistance
with the LA-ICPMS facility. Catherine Spaggiari and Russel Korsch
are thanked for thorough and constructive reviews which greatly
improved the manuscript. This work was supported by Australian
Research Council Grant LP0454301.
Appendix A. Supplementary data
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.precamres.2010.10.002.
References
Andersen, T., 2005. Detrital zircons as tracers of sedimentary provenance: limit-ing conditions from statistics and numerical simulation. Chemical Geology 216(3–4), 249–270.
Barovich, K., Hand, M., 2008. Tectonic setting and provenance of the Paleoprotero-zoic Willyama Supergroup, Curnamona Province, Australia: geochemical andNd isotopic constraints on contrasting source terrain components. PrecambrianResearch 166 (1–4), 318–337.
Belousova, E.A., Reid, A.J., Griffin, W.L., O’Reilly, S.Y., 2009. Rejuvenation vs. recyclingof Archean crust in the Gawler Craton, South Australia: evidence from U–Pb andHf isotopes in detrital zircon. Lithos 113, 570–582.
Betts, P.G., Giles, D., 2006. The 1800–1100 Ma tectonic evolution of Australia. Pre-cambrian Research 144 (1–2), 92–125.
Betts, P.G., Giles, D., Lister, G.S., Frick, L.R., 2002. Evolution of the Australian litho-sphere. Australian Journal of Earth Sciences 49 (4), 661–695.
Betts, P.G., Giles, D., Schaefer, B.F., 2008. Comparing 1800–1600 Ma accretionary andbasin processes in Australia and Laurentia: possible geographic connections inColumbia. Precambrian Research 166 (1–4), 81–82.
Betts, P.G., Valenta, R.K., Finlay, J., 2003. Evolution of the Mount Woods Inlier,northern Gawler Craton, Southern Australia: an integrated structural and aero-magnetic analysis. Tectonophysics 366 (1–2), 83–111.
Bizzarro, M., Baker, J.A., Haack, H., Ulfbeck, D., Rosing, M., 2003. Early history ofEarth’s crust–mantle system inferred from hafnium isotopes in chondrites.Nature 421 (6926), 931–933.
Black, L.P., Shaw, R.D., 1992. U–Pb zircon chronology of prograde Proterozoic eventsin the central and southern provinces of the Arunta Block, Central Australia.Australian Journal of Earth Sciences 39 (2), 153–171.
Blichert-Toft, J., Albarede, F., 1997. The Lu–Hf isotope geochemistry of chondrites andthe evolution of the mantle–crust system. Earth and Planetary Science Letters148 (1–2), 243–258.
Budd, A.R., Wyborn, L.A.I., Bastrakova, I.V., 2001. The metallogenic potential of Aus-tralian granites. Geoscience Australia Record, 12.
Cawood, P.A., Nemchin, A.A., Strachan, R., Prave, T., Krabbendam, M., 2007. Sedi-mentary basin and detrital zircon record along East Laurentia and Baltica duringassembly and breakup of Rodinia. Journal of the Geological Society 164, 257–275.
Chalmers, N.C., 2007. Mount Woods Domain: Proterozoic Metasediments and Intru-sives, South Australia. Department of Primary Industries and Resources, ReportBook/02.
Claoué-Long, J., Maidment, D., Hussey, K., Huston, D., 2008. The duration of theStrangways event in central Australia: evidence for prolonged deep crust pro-cesses. Precambrian Research 166 (1–4), 246–262.
Claoueı̌-Long, J., Maidment, D., Hussey, K., Huston, D., 2008. The duration of theStrangways event in central Australia: evidence for prolonged deep crust pro-cesses. Precambrian Research 166 (1–4), 246–262.
Claoué-Long, J.C., Hoatson, D.M., 2005. Proterozoic mafic-ultramafic intrusions inthe Arunta Region, central Australia. Part 2. Event chronology and regional cor-relations. Precambrian Research 142 (3–4), 134–158.
Collins, W.J., Shaw, R.D., 1995. Geochronological constraints on orogenic events inthe Arunta Inlier: a review. Precambrian Research 71 (1–4), 315–346.
Collins, W.J., Williams, I.S., 1995. SHRIMP ion-probe dating of short-lived Protero-zoic tectonic cycles in the northern Arunta Inlier, central Australia. PrecambrianResearch 71 (1–4), 69–89.
Conor, C.H.H., 1995. Moonta-Wallaroo Region: An Interpretation of the Geology ofthe Maitland and Wallaroo 1:100 000 Sheet Areas. South Australia Departmentof Mines and Energy, Open File Envelope 8886.
Copeland, P., Parrish, R.R., Harrison, T.M., 1988. Identification of inherited radiogenicPb in monazite and its implications for U–Pb systematics. Nature 333 (6175),760–763.
-71-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Cowley, W.M., Conor, C.H.H., Zang, W., 2003. New and revised Proterozoic strati-graphic units on northern Yorke Peninsula. MESA Journal 29, 46–58.
Daly, S.J., Fanning, C.M., Fairclough, M.C., 1998. Tectonic evolution and explorationpotential of the Gawler Craton, South Australia. AGSO Journal of AustralianGeology and Geophysics 17 (3), 145–168.
Dawson, G.C., Krapez, B., Fletcher, I.R., McNaughton, N.J., Rasmussen, B., 2002. Didlate Palaeoproterozoic assembly of proto-Australia involve collision betweenthe Pilbara, Yilgarn and Gawler cratons? Geochronological evidence from theMount Barren Group in the Albany-Fraser Orogen of Western Australia. Pre-cambrian Research 118 (3–4), 195–220.
DeBievre, P., Taylor, P.D.P., 1993. Table of the isotopic compositions of the ele-ments. International Journal of Mass Spectrometry and Ion Processes 123 (2),149–166.
Dickinson, W.R., Gehrels, G.E., 2003. U–Pb ages of detrital zircons from Permianand Jurassic eolian sandstones of the Colorado Plateau, USA: paleogeographicimplications. Sedimentary Geology 163 (1–2), 29–66.
Direen, N.G., Cadd, A.G., Lyons, P., Teasdale, J.P., 2005. Architecture of Proterozoicshear zones in the Christie Domain, western Gawler Craton, Australia: geophys-ical appraisal of a poorly exposed orogenic terrane. Precambrian Research 142(1–2), 28–44.
Dutch, R.A., Hand, M., Kelsey, D.E., 2010. Unravelling the tectonothermal evolutionof reworked Archean granulite facies metapelites using in situ geochronology:an example from the Gawler Craton, Australia. Journal of Metamorphic Geology28 (3), 293–316.
Fairclough, M.C., Schwarz, M., Ferris, G.M., 2003. Interpreted Crystalline BasementGeology of the Gawler Craton, South Australia (Special Map 1:1 000 000 scale).Primary Industries and Resources, South Australia, Adelaide.
Fanning, C.M., Flint, R.B., Parker, A.J., Ludwig, K.R., Blissett, A.H., 1988. Refined Pro-terozoic evolution of the Gawler Craton, South Australia, through U–Pb zircongeochronology. Precambrian Research 40–41, 363–386.
Fanning, C.M., Reid, A.J., Teale, G.S., 2007. A Geochronological framework for theGawler Craton, South Australia. Geological Survey Bulletin, 55.
Ferris, G., Schwarz, M., Heithersay, P., 2002. The geological framework, distributionand controls of Fe-oxide and related alteration, and Cu–Au mineralisation inthe Gawler Craton, South Australia. Part 1: Geological and Tectonic Framework.In: Porter, T. (Ed.), Hydrothermal Iron Oxide Copper-Gold & Related Deposits: AGlobal Perspective. PGC Publishing, Adelaide.
Fitzsimons, I.C.W., 2003. Proterozoic basement provinces of southern and south-western Australia, and their correlation with Antarctica. In: Yoshida, M.,Windley, B.F., Dasgupta, S. (Eds.), Proterozoic East Gondwana: SupercontinentAssembly and Breakup. Geological Society of London Special Publication 206,London, pp. 93–130.
Fitzsimons, I.C.W., Hulscher, B., 2005. Out of Africa: detrital zircon provenance ofcentral Madagascar and Neoproterozoic terrane transfer across the MozambiqueOcean. Terra Nova 17 (3), 224–235.
Fraser, G., McAvaney, S., Neumann, N., Szpunar, M., Reid, A., 2010. Discovery of earlyMesoarchean crust in the eastern Gawler Craton, South Australia. PrecambrianResearch 179 (1–4), 1–21.
Fraser, G.L., Lyons, P., 2006. Timing of Mesoproterozoic tectonic activity in thenorthwestern Gawler Craton constrained by Ar-40/Ar-39 geochronology. Pre-cambrian Research 151 (3–4), 160–184.
Giles, D., Betts, P., Lister, G., 2002. Far-field continental backarc setting for the1.80–1.67 Ga basins of northeastern Australia. Geology 30 (9), 823–826.
Giles, D., Betts, P.G., Lister, G.S., 2004. 1.8–1.5-Ga links between the North and SouthAustralian Cratons and the Early-Middle Proterozoic configuration of Australia.Tectonophysics 380, 27–41.
Griffin, W.L., Belousova, E.A., Shee, S.R., Pearson, N.J., O’Reilly, S.Y., 2004. Archeancrustal evolution in the northern Yilgam Craton: U–Pb and Hf-isotope evidencefrom detrital zircons. Precambrian Research 131 (3–4), 231–282.
Griffin, W.L., Belousova, E.A., Walters, S.G., O’Reilly, S.Y., 2006. Archaean and Protero-zoic crustal evolution in the Eastern Succession of the Mt Isa district, Australia:U–Pb and Hf-isotope studies of detrital zircons. Australian Journal of Earth Sci-ences 53 (1), 125–149.
Griffin, W.L., et al., 2000. The Hf isotope composition of cratonic mantle:LAM-MC-ICPMS analysis of zircon megacrysts in kimberlites. Geochimica EtCosmochimica Acta 64 (1), 133–147.
Hand, M., Reid, A., Jagodzinski, E., 2007. Tectonic framework and evolu-tion of the Gawler Craton, southern Australia. Economic Geology 102 (8),1377–1395.
Hoek, J.D., Schaefer, B.F., 1998. Palaeoproterozoic Kimban mobile belt, Eyre Penin-sula: timing and significance of felsic and mafic magmatism and deformation.Australian Journal of Earth Sciences 45 (2), 305–313.
Hopper, D.J., 2001. Crustal Evolution of Palaeo- to Mesoproterozoic Rocks in thePeake and Denison Ranges, South Australia. Unpublished Ph.D. Thesis. Brisbane,Australia, University of Queensland.
Howard, K.E., in preparation. Geotectonics in the Gawler Craton: Constraints fromGeochemistry, U–Pb geochronology and Sm–Nd and Lu–Hf Isotopes. PhD Thesis.University of Adelaide.
Howard, K.E., et al., 2009. Detrital zircon ages: Improving interpretation via Nd andHf isotopic data. Chemical Geology 262 (3–4), 277–292.
Huffadine, S.J., 1993. Environment, Timing and Petrogenesis of a Mid-ProterozoicVolcanic Suite: Pt Victoria, South Australia. Unpub. Honours Thesis. Universityof Adelaide.
Jackson, S.E., Pearson, N.J., Griffin, W.L., Belousova, E.A., 2004. The application of laserablation-inductively coupled plasma-mass spectrometry to in situ U–Pb zircongeochronology. Chemical Geology 211 (1–2), 47–69.
Jagodzinski, E., 2005. Compilation of SHRIMP U–Pb Geochronological Data, OlympicDomain, Gawler Craton, South Australia, 2001–2003. Geoscience Australia,Record 2005/20: 197.
Jagodzinski, E., et al., 2006. Compilation of SHRIMP U–Pb Geochronological Datafor the Gawler Craton, South Australia, 2006. South Australia. Department ofPrimary Industries and Resources. Report Book, 2006/20.
Jagodzinski, E.A., et al., 2007. Compilation of SHRIMP U–Pb Geochronological Datafor the Gawler Craton, South Australia, 2007. South Australia. Department ofPrimary Industries and Resources, Report Book, 2007/21.
Kirkland, C.L., Daly, J.S., Whitehouse, M.J., 2007. Provenance and terrane evolutionof the Kalak Nappe Complex, Norwegian Caledonides: implications for neopro-terozoic paleogeography and tectonics. Journal of Geology 115 (1), 21–41.
Maidment, D.W., Hand, M., Williams, I.S., 2005. Tectonic cycles in the Strang-ways Metamorphic Complex, Arunta Inlier, central Australia: geochronologicalevidence for exhumation and basin formation between two high-grade meta-morphic events. Australian Journal of Earth Sciences 52 (2), 205–215.
McLennan, S.M., et al., 2003. The roles of provenance and sedimentary processesin the geochemistry of sedimentary rocks. In: Lentz, D.R. (Ed.), Geochemistryof Sediments and Sedimentary Rocks: Evolutionary Considerations to MineralDeposit-Forming Environments. Geological Association of Canada, pp. 7–38.
Michard, A., Gurriet, P., Soudant, M., Albarede, F., 1985. Nd Isotopes in FrenchPhanerozoic Shales – External Vs Internal Aspects of Crustal Evolution. Geochim-ica Et Cosmochimica Acta 49, 601–610.
Myers, J.S., Shaw, R.D., Tyler, I.M., 1996. Tectonic evolution of Proterozoic Australia.Tectonics 15 (6), 1431–1446.
Nowell, G.M., et al., 1998. High precision Hf isotope measurements of MORB andOIB by thermal ionisation mass spectrometry: insights into the depleted mantle.Chemical Geology 149 (3–4), 211–233.
Oliver, R.L., Fanning, C.M., 1997. Australia and Antarctica; precise correlation ofPalaeoproterozoic terrains. In: R. C.A (Ed.), The Antarctic Region; GeologicalEvolution and Processes; Proceedings of the VII International Symposium onAntarctic Earth Sciences. International Symposium on Antarctic Earth Sciences.Terra Antarctica Publication, Siena, Italy, pp. 163–172.
Page, R.W., et al., 2005a. Correlation of Olary and Broken Hill Domains, Curna-mona Province: possible relationship to Mount Isa and other North AustralianPb–Zn–Ag-bearing successions. Economic Geology 100, 663–676.
Page, R.W., Stevens, B.P.J., Gibson, G.M., 2005b. Geochronology of the sequencehosting the Broken Hill Pb–Zn–Ag orebody, Australia. Economic Geology 100,633–651.
Patchett, P.J., et al., 1999. Nd isotopes, geochemistry, and constraints on sources ofsediments in the Franklinian mobile belt, Arctic Canada. Bulletin of the Geolog-ical Society of America 111 (4), 578–589.
Payne, J.L., Barovich, K.M., Hand, M., 2006. Provenance of metasedimentary rocksin the northern Gawler Craton, Australia: implications for Palaeoproterozoicreconstructions. Precambrian Research 148 (3–4), 275–291.
Payne, J.L., Ferris, G., Barovich, K.M., Hand, M., 2010. Pitfalls of classifying ancientmagmatic suites with tectonic discrimination diagrams: an example from thePaleoproterozoic Tunkillia Suite, southern Australia. Precambrian Research 177(3–4), 227–240.
Payne, J.L., Hand, M., Barovich, K.M., Reid, A., Evans, D.A.D., 2009. Correlationsand reconstruction models for the 2500–1500 Ma evolution of the MawsonContinent. In: Reddy, S.M., Mazumder, R., Evans, D.A.D., Collins, A.S. (Eds.),Palaeoproterozoic Supercontinents and Global Evolution. Geological Society,London, Special Publications, pp. 319–355.
Payne, J.L., Hand, M., Barovich, K.M., Wade, B.P., 2008. Temporal constraints on thetiming of high-grade metamorphism in the northern Gawler Craton: implica-tions for assembly of the Australian Proterozoic. Australian Journal of EarthSciences 55 (5), 623–640.
Rainbird, R.H., Hamilton, M.A., Young, G.M., 2001. Detrital zircon geochronology andprovenance of the Torridonian, NW Scotland. Journal of the Geological Society158 (1), 15–27.
Rankin, L.R., Flint, R.B., Fanning, C.M., 1990. The Bosanquet Formation of the GawlerCraton. South Australia Geological Survey. Quarterly Geological Notes 105,12–18.
Reid, A., Hand, M., Jagodzinski, E., Kelsey, D., Pearson, N., 2008. Paleoproterozoic oro-genesis in the southeastern Gawler Craton, South Australia. Australian Journalof Earth Sciences 55 (4), 449–471.
Roser, B.P., Korsch, R.J., 1986. Determination of tectonic setting ofsandstone–mudstone suites using SiO2 content and K2O/Na2O ratio. TheJournal of Geology 94 (5), 635–650.
Samson, S.D., D’Lemos, R.S., Miller, B.V., Hamilton, M.A., 2005. Neoproterozoicpalaeogeography of the Cadomia and Avalon terranes: constraints from detritalzircon U–Pb ages. Journal of the Geological Society 162, 65–71.
Schaefer, B.R., 1998. Insights into Proterozoic Tectonics from Southern Eyre Penin-sula, South Australia. Ph.D. Thesis. University of Adelaide, unpublished.
Scherer, E., Munker, C., Mezger, K., 2001. Calibration of the lutetium-hafnium clock.Science 293, 683–687.
Scrimgeour, I., Smith, J.B., Raith, J.G., 2001. Palaeoproterozoic high-T, low-P meta-morphism and dehydration melting in metapelites from the Mopunga Range,Arunta Inlier, central Australia. Journal of Metamorphic Geology 19 (6), 739–757.
Simpson, C.A., 1994. Constraints on Proterozoic Crustal Evolution from An Iso-topic and Geochemical Study of Clastic Sediments of the Gawler Craton, SouthAustralia. Honours Thesis. University of Adelaide.
Stewart, J.R., Betts, P.G., Collins, A.S., Schaefer, B.F., 2009. Multi-scale analysis ofProterozoic shear zones: an integrated structural and geophysical study. Journalof Structural Geology 31, 1238–1254.
-72-
Chapter 3 Provenance and depositi onal ti ming, western Gawler Craton
Sun, S.-s., Warren, R.G., Shaw, R.D., 1995. Nd isotope study of granites from theArunta Inlier, central Australia: constraints on geological models and limitationof the method. Precambrian Research 71 (1–4), 301–314.
Swain, G., Barovich, K., Hand, M., Ferris, G., Schwarz, M., 2008. Petrogenesis of the StPeter Suite, southern Australia: Arc magmatism and Proterozoic crustal growthof the South Australian Craton. Precambrian Research 166, 283–296.
Swain, G., et al., 2005a. Provenance and tectonic development of the late ArchaeanGawler Craton, Australia; U–Pb zircon, geochemical and Sm–Nd isotopic impli-cations. Precambrian Research 141 (3–4), 106–136.
Swain, G.M., Hand, M., Teasdale, J., Rutherford, L., Clark, C., 2005b. Age constraints onterrane-scale shear zones in the Gawler Craton, southern Australia. PrecambrianResearch 139 (3–4), 164–180.
Talavera-Mendoza, O., et al., 2005. U–Pb geochronology of the Acatlan Complexand implications for the Paleozoic paleogeography and tectonic evolution ofsouthern Mexico. Earth and Planetary Science Letters 235 (3–4), 682–699.
Taylor, S.R., McLennan, S.M., 1985. The Continental Crust: Its Composition and Evo-lution. Blackwell, Oxford, 312 pp.
Taylor, S.R., McLennan, S.M., 1995. The geochemical evolution of the continentalcrust. Reviews of Geophysics 33 (2), 241–265.
Teasdale, J., 1997. Methods for Understanding Poorly Exposed Terranes: The Inter-pretive Geology and Tectonothermal Evolution of the Western Gawler Craton.PhD Thesis. University of Adelaide, Adelaide, 179 pp.
Thiel, S., Heinson, G., 2010. Crustal imaging of a mobile belt using magnetotellurics:an example of the Fowler Domain in South Australia. Journal of GeophysicalResearch B: Solid Earth 115 (6).
Thomas, J.L., Direen, N.G., Hand, M., 2008. Blind orogen: integrated appraisal of mul-tiple episodes of Mesoproterozoic deformation and reworking in the FowlerDomain, western Gawler Craton, Australia. Precambrian Research 166 (1–4),263–282.
Vassallo, J.J., Wilson, C.J.L., 2002. Palaeoproterozoic regional-scale non-coaxial defor-mation; an example from eastern Eyre Peninsula, South Australia. Journal ofStructural Geology 24 (1), 1–24.
Wade, B.P., Barovich, K.M., Hand, M., Scrimgeour, I.R., Close, D.F., 2006. Evidence forearly Mesoproterozoic arc magmatism in the Musgrave Block, central Australia:Implications for Proterozoic crustal growth and tectonic reconstructions ofAustralia. Journal of Geology 114 (1), 43–63.
Wade, B.P., Hand, M., Barovich, K.M., 2005. Nd isotopic and geochemical constraintson provenance of sedimentary rocks in the eastern Officer Basin, Australia:implications for the duration of the intracratonic Petermann Orogeny. Journalof the Geological Society 162, 513–530.
Wade, B.P., Hand, M., Maidment, D.W., Close, D.F., Scrimgeour, I.R., 2008. Originof metasedimentary and igneous rocks from the Entia Dome, eastern AruntaRegion, central Australia: a U–Pb LA-ICPMS, SHRIMP and Sm–Nd isotope study.Australian Journal of Earth Sciences 55 (5), 703–719.
Werner, C.D., 1987. Saxonian Granulites—a contribution to the geochemical diag-nosis of original rocks in high-metamorphic complexes. Gerlands Beitrage zurGeophysik 96 (3–4), 271–290.
Zhao, J.X., Bennett, V.C., 1995. Shrimp U–Pb zircon geochronology of granites in theArunta-Inlier, Central Australia-implications for Proterozoic crustal evolution.Precambrian Research 71 (1–4), 17–43.
Zhao, J.X., Cooper, J.A., 1992. The Atnarpa Igneous Complex, southeast Arunta Inlier,central Australia: implications for subduction at an Early-Mid Proterozoic con-tinental margin. Precambrian Research 56, 227–253.
Zhao, J.X., McCulloch, M.T., 1995. Geochemical and Nd isotopic systematics ofgranites from the Arunta-Inlier, Central Australia—implications for Proterozoiccrustal evolution. Precambrian Research 71 (1–4), 265–299.
-73-
Chapter 3 Supplementary Material
Supp
lem
enta
ry T
able
1. U
-Pb
zirc
on d
ata
from
met
ased
imen
tary
rock
s of t
he F
owle
r Dom
ain
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
C
OL
20D
Z1
0.10
678
0.00
15
4.19
940
0.07
06
0.28
560
0.00
44
0.06
166
0.00
09
1745
25
16
20
22
1674
14
12
09
16
93Z2
0.
1315
2 0.
0013
6.
8170
5 0.
0902
0.
3760
5 0.
0050
0.
1321
5 0.
0015
21
18
18
2058
24
20
88
12
2509
26
97
Z4
0.10
640
0.00
11
4.32
110
0.05
74
0.29
464
0.00
39
0.08
058
0.00
08
1739
19
16
65
19
1697
11
15
66
15
96Z5
0.
1685
9 0.
0019
10
.711
46
0.15
54
0.46
096
0.00
66
0.14
260
0.00
17
2544
19
24
44
29
2498
13
26
95
30
96Z6
0.
1612
2 0.
0022
9.
2282
7 0.
1536
0.
4155
8 0.
0065
0.
0765
7 0.
0012
24
69
23
2240
30
23
61
15
1491
22
91
Z7
0.11
452
0.00
15
5.31
170
0.07
85
0.33
658
0.00
45
0.16
286
0.00
36
1872
23
18
70
22
1871
13
30
50
63
100
Z8
0.11
763
0.00
14
4.39
098
0.06
23
0.27
080
0.00
36
0.06
916
0.00
08
1921
21
15
45
18
1711
12
13
52
16
80Z9
0.
1136
7 0.
0013
3.
1020
1 0.
0436
0.
1979
6 0.
0027
0.
0755
8 0.
0009
18
59
20
1164
14
14
33
11
1473
17
63
Z10
0.11
593
0.00
13
4.31
197
0.06
27
0.26
980
0.00
39
0.06
624
0.00
08
1894
20
15
40
20
1696
12
12
96
14
81Z1
2 0.
1081
2 0.
0012
4.
4667
5 0.
0660
0.
2996
5 0.
0043
0.
0736
3 0.
0009
17
68
21
1690
21
17
25
12
1436
16
96
Z13
0.11
975
0.00
14
5.66
670
0.07
93
0.34
341
0.00
45
0.12
611
0.00
24
1952
21
19
03
22
1926
12
24
01
43
97Z1
6 0.
1123
0 0.
0011
4.
6162
8 0.
0606
0.
2981
6 0.
0040
0.
0817
1 0.
0008
18
37
18
1682
20
17
52
11
1588
15
92
Z17
0.12
774
0.00
20
6.21
715
0.09
94
0.35
304
0.00
47
0.14
671
0.00
48
2067
27
19
49
23
2007
14
27
67
85
94Z1
9 0.
1067
4 0.
0011
4.
9454
5 0.
0654
0.
3360
4 0.
0045
0.
0927
3 0.
0009
17
45
18
1868
22
18
10
11
1792
17
10
7Z2
0 0.
1093
7 0.
0011
4.
6433
6 0.
0611
0.
3079
3 0.
0041
0.
0947
7 0.
0010
17
89
19
1731
20
17
57
11
1830
19
97
Z21
0.11
989
0.00
12
5.86
326
0.07
63
0.35
476
0.00
47
0.09
878
0.00
10
1955
18
19
57
22
1956
11
19
04
19
100
Z22
0.12
135
0.00
19
6.08
325
0.10
10
0.36
354
0.00
52
0.13
331
0.00
32
1976
27
19
99
24
1988
14
25
29
57
101
Z23
0.11
110
0.00
12
3.90
536
0.05
59
0.25
500
0.00
36
0.07
748
0.00
10
1818
20
14
64
18
1615
12
15
08
18
81Z2
4 0.
1081
5 0.
0011
4.
4203
1 0.
0603
0.
2964
8 0.
0040
0.
0780
9 0.
0008
17
69
19
1674
20
17
16
11
1520
15
95
Z25*
0.
1040
9 0.
0012
4.
2797
0 0.
0588
0.
2982
2 0.
0040
0.
0853
2 0.
0010
16
98
21
1683
20
16
90
11
1655
18
99
Z27
0.11
912
0.00
14
4.08
477
0.06
00
0.24
888
0.00
35
0.09
709
0.00
19
1943
21
14
33
18
1651
12
18
73
35
74Z2
8 0.
1203
8 0.
0021
5.
4817
2 0.
0958
0.
3303
7 0.
0046
0.
2555
9 0.
0157
19
62
30
1840
22
18
98
15
4601
25
3 94
Z29
0.11
470
0.00
14
3.38
030
0.05
08
0.21
383
0.00
31
0.04
811
0.00
10
1875
22
12
49
16
1500
12
95
0 19
67
Z31
0.11
224
0.00
14
4.68
291
0.06
84
0.30
283
0.00
41
0.09
282
0.00
14
1836
23
17
05
20
1764
12
17
94
25
93Z3
3 0.
1045
8 0.
0012
4.
4029
8 0.
0577
0.
3053
3 0.
0038
0.
0819
4 0.
0009
17
07
21
1718
19
17
13
11
1592
16
10
1Z3
4 0.
1099
6 0.
0012
4.
3135
0 0.
0526
0.
2844
6 0.
0034
0.
0903
6 0.
0010
17
99
20
1614
17
16
96
10
1749
19
90
Z36
0.10
703
0.00
16
4.33
357
0.07
16
0.29
380
0.00
43
0.08
144
0.00
18
1749
26
16
61
21
1700
14
15
83
33
95Z3
7 0.
1984
8 0.
0020
13
.617
93
0.17
27
0.49
777
0.00
64
0.11
991
0.00
21
2814
17
26
04
28
2724
12
22
89
37
93Z3
9 0.
1058
9 0.
0011
4.
5387
4 0.
0576
0.
3108
9 0.
0039
0.
0853
6 0.
0009
17
30
19
1745
19
17
38
11
1656
18
10
1Z4
0 0.
2416
9 0.
0033
19
.707
10
0.30
97
0.59
212
0.00
90
0.19
020
0.00
71
3131
22
29
98
37
3077
15
35
20
121
96Z4
1 0.
1424
2 0.
0017
5.
3121
8 0.
0754
0.
2706
7 0.
0037
0.
0801
3 0.
0023
22
57
21
1544
19
18
71
12
1558
42
68
Z42
0.10
928
0.00
12
4.55
555
0.06
44
0.30
252
0.00
41
0.09
167
0.00
25
1787
20
17
04
21
1741
12
17
73
47
95Z4
3 0.
1058
8 0.
0012
4.
6271
5 0.
0586
0.
3169
8 0.
0039
0.
1026
3 0.
0021
17
30
20
1775
19
17
54
11
1975
39
10
3Z4
4*
0.10
355
0.00
11
4.18
630
0.05
22
0.29
320
0.00
35
0.08
385
0.00
11
1689
20
16
58
18
1671
10
16
28
20
98Z4
5 0.
1172
6 0.
0017
3.
9937
7 0.
0669
0.
2473
0 0.
0038
0.
1488
5 0.
0164
19
15
25
1425
20
16
33
14
2805
28
9 74
Z46
0.12
118
0.00
20
4.61
549
0.08
59
0.27
620
0.00
44
0.08
994
0.00
65
1974
29
15
72
22
1752
16
17
41
121
80Z4
7 0.
1085
7 0.
0014
4.
7720
7 0.
0668
0.
3189
8 0.
0041
0.
0880
1 0.
0013
17
76
23
1785
20
17
80
12
1705
25
10
1Z4
8 0.
1528
1 0.
0015
9.
1534
8 0.
1092
0.
4345
3 0.
0053
0.
1167
1 0.
0013
23
78
17
2326
24
23
54
11
2231
23
98
Z49
0.11
180
0.00
13
4.25
480
0.05
84
0.27
637
0.00
37
0.08
146
0.00
18
1829
20
15
73
18
1685
11
15
83
34
86Z5
0 0.
1130
0 0.
0013
3.
4415
8 0.
0480
0.
2213
6 0.
0030
0.
0549
5 0.
0010
18
48
21
1289
16
15
14
11
1081
19
70
Z51
0.20
182
0.00
26
14.0
0757
0.
2190
0.
5043
5 0.
0078
0.
1265
6 0.
0185
28
41
21
2633
33
27
50
15
2409
33
2 93
Z52
0.10
488
0.00
12
4.51
983
0.05
79
0.31
263
0.00
38
0.08
459
0.00
13
1712
20
17
54
19
1735
11
16
41
24
102
-74-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
C
OL
20D
(con
tinue
d)Z5
3 0.
1258
8 0.
0017
4.
6815
5 0.
0693
0.
2696
6 0.
0035
0.
0896
7 0.
0028
20
41
24
1539
18
17
64
12
1736
51
75
Z54*
0.
1048
6 0.
0014
4.
7652
4 0.
0694
0.
3298
4 0.
0043
0.
0926
2 0.
0019
17
12
24
1838
21
17
79
12
1790
34
10
7Z5
5 0.
1122
1 0.
0013
4.
9646
0 0.
0668
0.
3211
1 0.
0041
0.
0940
3 0.
0018
18
36
20
1795
20
18
13
11
1816
34
98
Z56
0.10
905
0.00
13
4.83
023
0.06
56
0.32
131
0.00
41
0.09
243
0.00
27
1784
22
17
96
20
1790
11
17
87
50
101
Z57
0.10
903
0.00
15
4.29
732
0.06
32
0.28
603
0.00
37
0.06
896
0.00
19
1783
24
16
22
19
1693
12
13
48
36
91Z5
8*
0.10
281
0.00
12
4.52
888
0.05
92
0.31
952
0.00
40
0.09
048
0.00
12
1676
21
17
87
19
1736
11
17
51
22
107
Z59
0.12
628
0.00
19
5.15
206
0.08
46
0.29
612
0.00
43
0.09
652
0.00
54
2047
26
16
72
21
1845
14
18
62
100
82Z6
0*
0.10
457
0.00
12
4.59
992
0.05
73
0.31
905
0.00
38
0.09
091
0.00
13
1707
20
17
85
19
1749
10
17
59
25
105
B
AC
18
Z1
0.10
605
0.00
13
0.23
131
0.00
35
3.38
166
0.05
40
0.00
661
0.00
01
1733
23
13
41
18
1500
13
13
3 2
77Z2
0.
1054
3 0.
0017
0.
2424
4 0.
0038
3.
5233
2 0.
0657
0.
0063
8 0.
0002
17
22
30
1399
20
15
33
15
129
4 81
Z3
0.10
379
0.00
18
0.26
260
0.00
45
3.75
624
0.07
64
0.07
859
0.00
31
1693
31
15
03
23
1583
16
15
29
58
89Z4
0.
1091
7 0.
0012
0.
2159
8 0.
0033
3.
2502
4 0.
0501
0.
0072
5 0.
0001
17
86
20
1261
17
14
69
12
146
2 71
Z5
0.10
615
0.00
15
0.19
332
0.00
31
2.82
863
0.04
93
0.00
707
0.00
02
1734
25
11
39
17
1363
13
14
2 3
66Z6
0.
1075
2 0.
0015
0.
2577
2 0.
0041
3.
8198
5 0.
0667
0.
0183
3 0.
0005
17
58
25
1478
21
15
97
14
367
9 84
Z7
0.10
720
0.00
11
0.24
713
0.00
38
3.65
179
0.05
61
0.00
873
0.00
01
1752
19
14
24
20
1561
12
17
6 2
81Z8
0.
1068
4 0.
0013
0.
2497
1 0.
0037
3.
6764
2 0.
0582
0.
0208
3 0.
0003
17
46
23
1437
19
15
66
13
417
6 82
Z9
0.10
764
0.00
12
0.25
621
0.00
40
3.80
167
0.06
07
0.01
901
0.00
03
1760
21
14
70
20
1593
13
38
1 5
84Z1
0 0.
1067
5 0.
0013
0.
2961
1 0.
0047
4.
3560
1 0.
0720
0.
0327
0 0.
0004
17
45
22
1672
23
17
04
14
650
9 96
Z11
0.10
607
0.00
11
0.26
054
0.00
39
3.80
905
0.05
71
0.01
418
0.00
02
1733
19
14
93
20
1595
12
28
5 4
86Z1
2 0.
1117
8 0.
0014
0.
1594
1 0.
0026
2.
4561
7 0.
0420
0.
0042
4 0.
0001
18
29
23
954
15
1259
12
86
1
52Z1
3 0.
1213
2 0.
0016
0.
1421
1 0.
0024
2.
3765
4 0.
0422
0.
0060
7 0.
0001
19
76
24
857
14
1236
13
12
2 2
43Z1
4 0.
1103
9 0.
0013
0.
1779
4 0.
0026
2.
7069
7 0.
0412
0.
0102
6 0.
0002
18
06
21
1056
14
13
30
11
206
3 58
Z15
0.10
838
0.00
14
0.25
354
0.00
41
3.78
682
0.06
50
0.02
796
0.00
05
1772
23
14
57
21
1590
14
55
7 10
82
Z16
0.10
800
0.00
13
0.28
549
0.00
48
4.24
893
0.07
26
0.03
331
0.00
06
1766
22
16
19
24
1684
14
66
2 11
92
Z17
0.10
980
0.00
14
0.21
414
0.00
36
3.23
971
0.05
65
0.01
857
0.00
03
1796
23
12
51
19
1467
14
37
2 7
70Z1
8 0.
1098
6 0.
0013
0.
1839
6 0.
0030
2.
7855
0 0.
0464
0.
0106
8 0.
0002
17
97
21
1089
16
13
52
12
215
3 61
Z19
0.10
672
0.00
12
0.27
182
0.00
47
4.00
284
0.06
79
0.01
342
0.00
03
1744
21
15
50
24
1635
14
27
0 5
89Z2
0 0.
1051
3 0.
0012
0.
2145
9 0.
0034
3.
1096
8 0.
0493
0.
0073
6 0.
0001
17
17
20
1253
18
14
35
12
148
2 73
Z21
0.11
723
0.00
18
0.12
124
0.00
22
1.95
864
0.03
76
0.00
517
0.00
02
1915
27
73
8 13
11
01
13
104
3 39
Z22
0.10
949
0.00
13
0.23
050
0.00
36
3.47
949
0.05
57
0.00
754
0.00
01
1791
21
13
37
19
1523
13
15
2 3
75Z2
3 0.
1084
6 0.
0015
0.
2600
5 0.
0046
3.
8883
7 0.
0710
0.
0320
5 0.
0009
17
74
25
1490
23
16
11
15
638
17
84Z2
4 0.
1055
6 0.
0011
0.
2018
5 0.
0031
2.
9377
8 0.
0445
0.
0141
7 0.
0002
17
24
20
1185
16
13
92
11
284
4 69
Z25
0.11
285
0.00
14
0.14
545
0.00
23
2.26
321
0.03
69
0.00
897
0.00
02
1846
22
87
5 13
12
01
11
180
3 47
Z26
0.10
673
0.00
11
0.20
934
0.00
32
3.08
047
0.04
73
0.00
573
0.00
01
1744
19
12
25
17
1428
12
11
6 2
70Z2
7 0.
1059
0 0.
0011
0.
2765
2 0.
0042
4.
0376
2 0.
0596
0.
0313
2 0.
0004
17
30
18
1574
21
16
42
12
623
7 91
Z28
0.11
459
0.00
16
0.17
253
0.00
31
2.72
574
0.05
00
0.00
624
0.00
02
1873
25
10
26
17
1336
14
12
6 4
55Z2
9 0.
1177
0 0.
0015
0.
1195
6 0.
0021
1.
9404
9 0.
0341
0.
0053
8 0.
0001
19
22
23
728
12
1095
12
10
8 3
38Z3
0 0.
1126
7 0.
0013
0.
1568
3 0.
0025
2.
4367
0 0.
0391
0.
0052
8 0.
0001
18
43
20
939
14
1254
12
10
7 2
51Z3
1 0.
1050
4 0.
0012
0.
2367
8 0.
0036
3.
4275
6 0.
0523
0.
0389
9 0.
0006
17
15
20
1370
19
15
11
12
773
11
80Z3
2 0.
1069
1 0.
0012
0.
2449
9 0.
0036
3.
6095
9 0.
0538
0.
0313
2 0.
0005
17
47
20
1413
18
15
52
12
623
9 81
Z33
0.11
536
0.00
13
0.13
256
0.00
19
2.10
779
0.03
04
0.00
703
0.00
01
1885
20
80
3 11
11
51
10
142
2 43
Z34
0.10
734
0.00
11
0.26
367
0.00
38
3.90
150
0.05
56
0.04
877
0.00
06
1755
19
15
09
19
1614
12
96
3 11
86
Z35
0.10
752
0.00
12
0.29
325
0.00
42
4.34
638
0.06
36
0.06
614
0.00
08
1758
20
16
58
21
1702
12
12
95
15
94
-75-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
B
AC
18
Z36
0.11
567
0.00
17
0.26
611
0.00
43
4.23
294
0.07
36
0.04
756
0.00
13
1890
26
15
21
22
1680
14
93
9 25
80
Z37
0.10
548
0.00
11
0.28
377
0.00
40
4.12
604
0.05
79
0.08
086
0.00
09
1723
18
16
10
20
1660
11
15
72
17
93Z3
8 0.
1060
9 0.
0011
0.
2811
0 0.
0040
4.
1104
1 0.
0574
0.
0681
1 0.
0008
17
33
18
1597
20
16
56
11
1332
14
92
Z39
0.10
726
0.00
11
0.23
572
0.00
34
3.48
499
0.04
99
0.03
247
0.00
04
1753
19
13
64
18
1524
11
64
6 8
78Z4
0 0.
1457
3 0.
0020
0.
0676
6 0.
0011
1.
3563
7 0.
0225
0.
0039
0 0.
0001
22
96
23
422
6 87
0 10
79
2
18Z4
1 0.
1049
7 0.
0011
0.
2487
2 0.
0036
3.
5995
0 0.
0527
0.
0342
7 0.
0005
17
14
20
1432
19
15
49
12
681
9 84
Z42
0.10
375
0.00
11
0.16
555
0.00
24
2.36
758
0.03
42
0.03
850
0.00
05
1692
19
98
8 13
12
33
10
764
10
58Z4
3 0.
1052
6 0.
0012
0.
2813
5 0.
0042
4.
0826
5 0.
0623
0.
0443
6 0.
0007
17
19
21
1598
21
16
51
12
877
13
93Z4
4 0.
1089
6 0.
0014
0.
2213
9 0.
0031
3.
3272
8 0.
0507
0.
0291
6 0.
0009
17
82
23
1289
16
14
88
12
581
18
72Z4
5 0.
1087
8 0.
0012
0.
2568
2 0.
0037
3.
8518
8 0.
0558
0.
0081
7 0.
0001
17
79
20
1474
19
16
04
12
165
2 83
Z46
0.11
009
0.00
15
0.18
075
0.00
25
2.74
415
0.04
26
0.00
780
0.00
02
1801
24
10
71
14
1341
12
15
7 4
59Z4
7 0.
1086
2 0.
0011
0.
1367
3 0.
0019
2.
0478
8 0.
0288
0.
0315
5 0.
0006
17
76
19
826
11
1132
10
62
8 11
47
Z48
0.10
648
0.00
12
0.24
994
0.00
36
3.66
936
0.05
44
0.01
582
0.00
02
1740
20
14
38
19
1565
12
31
7 5
83Z4
9 0.
1540
0 0.
0018
0.
1102
4 0.
0017
2.
3406
8 0.
0362
0.
0093
0 0.
0002
23
91
20
674
10
1225
11
18
7 4
28Z5
0 0.
1095
1 0.
0012
0.
2414
4 0.
0035
3.
6458
6 0.
0535
0.
0246
4 0.
0004
17
91
20
1394
18
15
60
12
492
7 78
B
AC
23
Z1
0.10
818
0.00
14
0.27
945
0.00
34
4.16
760
0.05
71
0.07
495
0.00
17
1769
23
15
89
17
1668
11
14
61
31
90Z2
0.
1072
4 0.
0012
0.
2355
8 0.
0028
3.
4826
0 0.
0434
0.
0633
5 0.
0008
17
53
20
1364
15
15
23
10
1242
15
78
Z3
0.12
136
0.00
14
0.11
621
0.00
14
1.94
369
0.02
49
0.03
171
0.00
04
1976
21
70
9 8
1096
9
631
8 36
Z4
0.11
325
0.00
15
0.23
809
0.00
30
3.71
769
0.05
31
0.06
255
0.00
11
1852
24
13
77
16
1575
11
12
26
21
74Z5
0.
1578
3 0.
0020
0.
1188
8 0.
0015
2.
5866
1 0.
0351
0.
0278
2 0.
0004
24
33
21
724
9 12
97
10
555
8 30
Z6
0.10
806
0.00
13
0.18
724
0.00
23
2.78
886
0.03
68
0.05
337
0.00
09
1767
22
11
06
12
1353
10
10
51
17
63Z7
0.
1158
0 0.
0016
0.
1193
8 0.
0015
1.
9056
0 0.
0273
0.
0335
4 0.
0006
18
92
25
727
8 10
83
10
667
12
38Z8
0.
1061
4 0.
0012
0.
2735
7 0.
0034
4.
0023
9 0.
0528
0.
0757
2 0.
0009
17
34
21
1559
17
16
35
11
1475
17
90
Z9
0.12
503
0.00
16
0.14
145
0.00
19
2.43
790
0.03
61
0.02
586
0.00
04
2029
23
85
3 11
12
54
11
516
7 42
Z10
0.11
067
0.00
15
0.23
338
0.00
32
3.56
320
0.05
55
0.05
872
0.00
16
1811
24
13
52
17
1541
12
11
53
31
75Z1
1 0.
1185
5 0.
0016
0.
1191
4 0.
0017
1.
9453
6 0.
0304
0.
0265
5 0.
0006
19
35
25
726
10
1097
10
53
0 11
38
Z12
0.10
329
0.00
13
0.29
243
0.00
37
4.16
581
0.05
75
0.07
714
0.00
11
1684
23
16
54
18
1667
11
15
02
21
98Z1
3 0.
1441
4 0.
0017
0.
4154
1 0.
0055
8.
2494
1 0.
1141
0.
0747
3 0.
0030
22
78
20
2240
25
22
59
13
1457
57
98
Z14
0.10
785
0.00
15
0.26
835
0.00
34
3.98
612
0.05
78
0.07
521
0.00
16
1763
25
15
32
17
1631
12
14
66
29
87Z1
5 0.
1068
3 0.
0012
0.
2889
3 0.
0036
4.
2561
6 0.
0551
0.
0736
1 0.
0009
17
46
20
1636
18
16
85
11
1436
17
94
Z16
0.10
515
0.00
13
0.26
490
0.00
37
3.83
518
0.05
70
0.06
291
0.00
11
1717
23
15
15
19
1600
12
12
33
20
88Z1
7 0.
1084
3 0.
0015
0.
2882
5 0.
0040
4.
3040
6 0.
0662
0.
0603
4 0.
0011
17
73
25
1633
20
16
94
13
1184
21
92
Z18
0.10
718
0.00
14
0.27
915
0.00
38
4.11
970
0.06
04
0.06
713
0.00
13
1752
23
15
87
19
1658
12
13
13
24
91Z1
9 0.
1078
4 0.
0013
0.
1845
1 0.
0023
2.
7417
7 0.
0369
0.
0487
6 0.
0008
17
63
23
1092
12
13
40
10
962
16
62Z2
0 0.
1026
9 0.
0013
0.
2959
8 0.
0038
4.
1897
1 0.
0594
0.
0773
5 0.
0018
16
73
24
1671
19
16
72
12
1506
34
10
0Z2
1 0.
1086
1 0.
0014
0.
1195
5 0.
0015
1.
7893
9 0.
0244
0.
0267
8 0.
0007
17
76
23
728
8 10
42
9 53
4 13
41
Z22
0.10
882
0.00
14
0.22
620
0.00
30
3.39
043
0.04
97
0.04
817
0.00
09
1780
23
13
15
16
1502
11
95
1 17
74
Z23
0.11
742
0.00
14
0.17
925
0.00
22
2.90
193
0.03
83
0.05
179
0.00
08
1917
21
10
63
12
1382
10
10
21
16
55Z2
4 0.
1167
6 0.
0013
0.
3202
0 0.
0039
5.
1543
6 0.
0657
0.
0868
5 0.
0017
19
07
20
1791
19
18
45
11
1683
32
94
Z25
0.11
398
0.00
13
0.07
245
0.00
09
1.13
857
0.01
46
0.01
337
0.00
02
1864
20
45
1 5
772
7 26
8 4
24Z2
6 0.
1123
5 0.
0013
0.
1654
9 0.
0021
2.
5632
9 0.
0342
0.
0436
1 0.
0008
18
38
21
987
11
1290
10
86
3 15
54
Z27
0.11
681
0.00
14
0.12
072
0.00
15
1.94
374
0.02
60
0.02
292
0.00
04
1908
21
73
5 9
1096
9
458
9 39
Z28
0.10
382
0.00
11
0.27
728
0.00
34
3.96
879
0.04
95
0.07
801
0.00
12
1693
20
15
78
17
1628
10
15
18
23
93
-76-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
B
AC
23
(con
tinue
d)Z2
9 0.
1138
3 0.
0015
0.
0915
2 0.
0012
1.
4367
8 0.
0208
0.
0250
7 0.
0007
18
62
24
565
7 90
4 9
501
13
30Z3
0 0.
1111
3 0.
0013
0.
2987
0 0.
0036
4.
5752
8 0.
0597
0.
0870
3 0.
0013
18
18
22
1685
18
17
45
11
1687
24
93
B
AC
23
sess
ion
2
Z01
0.10
283
0.00
15
0.29
928
0.00
42
4.24
116
0.06
90
0.07
697
0.00
22
1676
26
16
88
21
1682
13
14
99
42
101
Z02
0.10
696
0.00
12
0.24
260
0.00
32
3.57
819
0.04
81
0.06
597
0.00
08
1748
20
14
00
16
1545
11
12
91
15
80Z0
3 0.
1038
1 0.
0019
0.
2960
3 0.
0046
4.
2353
0 0.
0832
0.
0670
1 0.
0028
16
93
33
1672
23
16
81
16
1311
52
99
Z04
0.10
544
0.00
22
0.28
844
0.00
47
4.19
484
0.09
27
0.06
038
0.00
14
1722
38
16
34
23
1673
18
11
85
27
95Z0
5 0.
1067
6 0.
0013
0.
2771
8 0.
0037
4.
0798
7 0.
0575
0.
0705
6 0.
0010
17
45
21
1577
19
16
50
12
1378
19
90
Z06
0.10
800
0.00
14
0.32
021
0.00
46
4.76
447
0.07
55
0.07
776
0.00
13
1766
24
17
91
22
1779
13
15
14
24
101
Z07
0.10
727
0.00
13
0.16
739
0.00
22
2.47
540
0.03
54
0.02
305
0.00
04
1754
23
99
8 12
12
65
10
461
9 57
Z08
0.10
877
0.00
13
0.20
371
0.00
29
3.05
358
0.04
59
0.05
209
0.00
08
1779
22
11
95
15
1421
12
10
26
15
67Z0
9 0.
1099
6 0.
0012
0.
1341
4 0.
0018
2.
0336
1 0.
0275
0.
0247
8 0.
0003
17
99
20
812
10
1127
9
495
6 45
Z10
0.10
001
0.00
13
0.30
057
0.00
42
4.14
240
0.06
50
0.07
310
0.00
20
1624
25
16
94
21
1663
13
14
26
37
104
Z11
0.10
558
0.00
12
0.29
442
0.00
38
4.28
588
0.05
78
0.07
143
0.00
13
1725
20
16
64
19
1691
11
13
95
25
96Z1
2 0.
1056
1 0.
0012
0.
2779
7 0.
0036
4.
0474
5 0.
0560
0.
0828
7 0.
0014
17
25
21
1581
18
16
44
11
1609
25
92
Z13
0.11
064
0.00
12
0.11
053
0.00
15
1.68
581
0.02
33
0.01
582
0.00
03
1810
20
67
6 9
1003
9
317
5 37
Z14
0.10
887
0.00
18
0.31
528
0.00
49
4.72
730
0.08
85
0.06
958
0.00
16
1781
30
17
67
24
1772
16
13
60
31
99Z1
5 0.
1064
2 0.
0013
0.
2465
9 0.
0032
3.
6177
6 0.
0506
0.
0709
7 0.
0013
17
39
22
1421
17
15
53
11
1386
24
82
Z16
0.10
781
0.00
16
0.30
112
0.00
44
4.47
416
0.07
50
0.08
638
0.00
27
1763
26
16
97
22
1726
14
16
75
51
96Z1
7 0.
1055
7 0.
0014
0.
2426
6 0.
0035
3.
5302
6 0.
0551
0.
0592
9 0.
0013
17
24
23
1401
18
15
34
12
1164
24
81
Z18
0.11
662
0.00
16
0.10
873
0.00
16
1.74
795
0.02
80
0.02
910
0.00
05
1905
24
66
5 9
1026
10
58
0 11
35
Z19
0.11
175
0.00
14
0.11
672
0.00
16
1.79
806
0.02
74
0.02
926
0.00
05
1828
23
71
2 9
1045
10
58
3 11
39
Z20
0.10
476
0.00
12
0.28
370
0.00
38
4.09
760
0.05
79
0.07
321
0.00
18
1710
21
16
10
19
1654
12
14
28
33
94Z2
1 0.
1096
5 0.
0013
0.
3004
7 0.
0041
4.
5411
0 0.
0661
0.
0711
2 0.
0017
17
94
22
1694
20
17
39
12
1389
32
94
Z22
0.10
603
0.00
13
0.30
595
0.00
42
4.47
101
0.06
70
0.07
997
0.00
16
1732
23
17
21
21
1726
12
15
55
30
99Z2
3 0.
1132
8 0.
0013
0.
0993
8 0.
0013
1.
5514
3 0.
0218
0.
0216
1 0.
0004
18
53
20
611
8 95
1 9
432
8 33
Z24
0.10
520
0.00
15
0.26
363
0.00
40
3.81
550
0.06
56
0.04
804
0.00
19
1718
27
15
08
20
1596
14
94
8 37
88
Z25
0.10
519
0.00
15
0.29
069
0.00
40
4.21
383
0.06
69
0.07
207
0.00
17
1718
25
16
45
20
1677
13
14
07
31
96Z2
6 0.
1063
5 0.
0018
0.
2843
0 0.
0043
4.
1648
9 0.
0780
0.
0694
5 0.
0023
17
38
31
1613
22
16
67
15
1357
44
93
Z27
0.10
448
0.00
12
0.29
029
0.00
39
4.17
925
0.06
01
0.07
716
0.00
15
1705
22
16
43
19
1670
12
15
02
29
96Z2
8 0.
1065
6 0.
0012
0.
2965
0 0.
0040
4.
3536
7 0.
0618
0.
0835
8 0.
0016
17
42
21
1674
20
17
04
12
1622
30
96
Z29
0.10
784
0.00
14
0.31
667
0.00
44
4.70
723
0.07
16
0.08
418
0.00
20
1763
23
17
73
21
1769
13
16
34
38
101
Z30
0.11
263
0.00
17
0.09
442
0.00
14
1.45
968
0.02
54
0.01
540
0.00
06
1842
26
58
2 8
914
10
309
12
32
BA
C 4
1Z1
0.
1122
7 0.
0012
0.
2631
9 0.
0041
4.
0741
3 0.
0636
0.
0882
1 0.
0011
18
36
19
1506
21
16
49
13
1709
21
82
Z2
0.10
405
0.00
12
0.29
730
0.00
53
4.26
465
0.07
60
0.07
580
0.00
10
1698
21
16
78
27
1687
15
14
77
19
99Z3
0.
1056
3 0.
0014
0.
2807
5 0.
0052
4.
0882
2 0.
0779
0.
0702
6 0.
0012
17
25
24
1595
26
16
52
16
1372
22
92
Z4
0.11
123
0.00
13
0.28
362
0.00
48
4.34
873
0.07
41
0.08
868
0.00
13
1820
21
16
10
24
1703
14
17
17
24
88Z5
0.
1054
0 0.
0011
0.
3152
4 0.
0051
4.
5810
5 0.
0732
0.
0924
2 0.
0011
17
21
19
1766
25
17
46
13
1787
21
10
3Z6
0.
1113
8 0.
0011
0.
1986
1 0.
0033
3.
0491
1 0.
0497
0.
0528
4 0.
0006
18
22
19
1168
18
14
20
12
1041
12
64
-77-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
B
AC
41
(con
tinue
d)Z7
0.
1057
5 0.
0011
0.
2804
1 0.
0046
4.
0883
3 0.
0660
0.
0820
1 0.
0010
17
27
19
1593
23
16
52
13
1593
18
92
Z8
0.10
601
0.00
11
0.31
077
0.00
50
4.54
218
0.07
15
0.08
613
0.00
10
1732
18
17
45
24
1739
13
16
70
19
101
Z9
0.10
546
0.00
11
0.30
901
0.00
50
4.49
317
0.07
23
0.08
478
0.00
11
1722
19
17
36
25
1730
13
16
45
20
101
Z10
0.10
516
0.00
12
0.23
105
0.00
44
3.35
015
0.06
21
0.05
691
0.00
10
1717
21
13
40
23
1493
15
11
19
20
78Z1
1 0.
1052
2 0.
0015
0.
2776
4 0.
0055
4.
0263
0 0.
0811
0.
0603
6 0.
0019
17
18
26
1580
27
16
40
16
1185
36
92
Z12
0.12
301
0.00
17
0.13
704
0.00
24
2.32
409
0.04
23
0.01
299
0.00
02
2000
24
82
8 13
12
20
13
261
5 41
Z13
0.11
089
0.00
13
0.17
169
0.00
27
2.62
499
0.04
26
0.05
550
0.00
09
1814
21
10
21
15
1308
12
10
92
17
56Z1
4 0.
1019
2 0.
0015
0.
2191
9 0.
0037
3.
0714
1 0.
0538
0.
1937
3 0.
0249
16
59
27
1278
20
14
26
13
3579
42
2 77
Z15
0.10
608
0.00
11
0.31
621
0.00
52
4.62
435
0.07
44
0.08
607
0.00
10
1733
18
17
71
25
1754
13
16
69
19
102
Z16
0.10
906
0.00
12
0.27
132
0.00
43
4.07
919
0.06
37
0.07
295
0.00
13
1784
19
15
48
22
1650
13
14
23
25
87Z1
8 0.
1066
5 0.
0012
0.
2750
0 0.
0045
4.
0430
1 0.
0664
0.
0775
5 0.
0011
17
43
20
1566
23
16
43
13
1510
20
90
Z19
0.10
762
0.00
12
0.23
919
0.00
43
3.54
935
0.06
33
0.06
035
0.00
11
1760
21
13
83
22
1538
14
11
84
21
79Z2
0 0.
1064
1 0.
0011
0.
2946
1 0.
0050
4.
3216
8 0.
0726
0.
0911
0 0.
0013
17
39
19
1665
25
16
98
14
1762
23
96
Z21
0.10
637
0.00
12
0.28
811
0.00
44
4.22
138
0.06
61
0.10
375
0.00
22
1738
21
16
32
22
1678
13
19
95
40
94Z2
2 0.
1054
5 0.
0012
0.
3014
2 0.
0044
4.
3812
8 0.
0645
0.
0795
1 0.
0010
17
22
20
1698
22
17
09
12
1546
19
99
Z23
0.10
938
0.00
12
0.25
759
0.00
40
3.88
330
0.06
04
0.06
083
0.00
12
1789
20
14
78
20
1610
13
11
94
23
83Z2
4 0.
1086
1 0.
0012
0.
2785
9 0.
0042
4.
1704
3 0.
0635
0.
0689
4 0.
0010
17
76
20
1584
21
16
68
12
1348
19
89
Z25
0.10
700
0.00
13
0.22
474
0.00
34
3.31
383
0.05
24
0.06
043
0.00
12
1749
22
13
07
18
1484
12
11
86
22
75Z2
6 0.
1064
0 0.
0012
0.
2863
2 0.
0041
4.
1997
5 0.
0616
0.
0834
5 0.
0010
17
39
20
1623
21
16
74
12
1620
19
93
Z28
0.10
704
0.00
11
0.27
941
0.00
39
4.12
377
0.05
70
0.08
410
0.00
10
1750
19
15
88
19
1659
11
16
32
19
91Z2
9 0.
1050
2 0.
0011
0.
3005
1 0.
0042
4.
3511
2 0.
0601
0.
0856
6 0.
0010
17
15
19
1694
21
17
03
11
1661
19
99
Z30
0.10
878
0.00
15
0.16
564
0.00
27
2.48
385
0.04
30
0.03
566
0.00
11
1779
25
98
8 15
12
67
13
708
21
56Z3
1 0.
1057
1 0.
0011
0.
3000
6 0.
0043
4.
3727
7 0.
0621
0.
0848
8 0.
0013
17
27
19
1692
21
17
07
12
1647
24
98
Z32
0.10
681
0.00
11
0.27
940
0.00
42
4.11
883
0.06
14
0.07
931
0.00
17
1746
19
15
88
21
1658
12
15
43
32
91Z3
3 0.
1058
0 0.
0013
0.
2867
8 0.
0043
4.
1855
6 0.
0651
0.
0788
5 0.
0014
17
28
21
1625
22
16
71
13
1534
25
94
Z34
0.10
696
0.00
12
0.26
972
0.00
39
3.97
739
0.05
86
0.07
561
0.00
10
1748
20
15
39
20
1630
12
14
73
19
88Z3
5 0.
1057
9 0.
0011
0.
2993
8 0.
0042
4.
3663
3 0.
0600
0.
0849
6 0.
0010
17
28
19
1688
21
17
06
11
1648
19
98
Z36
0.10
768
0.00
12
0.28
972
0.00
45
4.30
325
0.06
63
0.06
290
0.00
18
1760
20
16
40
22
1694
13
12
33
34
93Z3
7 0.
1053
4 0.
0012
0.
2971
5 0.
0044
4.
3166
1 0.
0652
0.
0790
0 0.
0019
17
20
21
1677
22
16
97
12
1537
35
97
Z38
0.11
865
0.00
13
0.13
297
0.00
19
2.17
499
0.03
15
0.03
677
0.00
06
1936
19
80
5 11
11
73
10
730
11
42Z3
9 0.
1094
4 0.
0012
0.
2147
7 0.
0032
3.
2414
7 0.
0483
0.
0739
6 0.
0017
17
90
20
1254
17
14
67
12
1442
32
70
Z40
0.10
554
0.00
11
0.30
744
0.00
44
4.47
275
0.06
37
0.09
051
0.00
16
1724
19
17
28
22
1726
12
17
51
29
100
B
AC
41
sess
ion
2z0
1 0.
1047
0 0.
0012
0.
2670
0 0.
0033
3.
8531
7 0.
0497
0.
0937
7 0.
0014
17
09
21
1526
17
16
04
10
1812
26
89
z02
0.11
210
0.00
12
0.30
806
0.00
40
4.75
902
0.06
24
0.09
065
0.00
12
1834
19
17
31
20
1778
11
17
54
22
94z0
3 0.
1056
2 0.
0013
0.
3026
2 0.
0042
4.
4018
5 0.
0651
0.
0785
6 0.
0011
17
25
22
1704
21
17
13
12
1529
21
99
z04
0.10
558
0.00
12
0.30
697
0.00
41
4.46
518
0.06
23
0.09
282
0.00
14
1724
21
17
26
20
1725
12
17
94
25
100
z05
0.10
587
0.00
12
0.30
874
0.00
41
4.50
237
0.06
28
0.08
628
0.00
13
1729
21
17
35
20
1731
12
16
73
23
100
z06
0.10
470
0.00
12
0.26
617
0.00
37
3.83
733
0.05
58
0.07
086
0.00
10
1709
22
15
21
19
1601
12
13
84
19
89z0
7 0.
1066
7 0.
0012
0.
3124
6 0.
0042
4.
5917
8 0.
0641
0.
0861
1 0.
0012
17
43
20
1753
21
17
48
12
1670
22
10
1z0
8 0.
1068
4 0.
0012
0.
2999
9 0.
0039
4.
4156
5 0.
0593
0.
0863
6 0.
0011
17
46
20
1691
20
17
15
11
1674
21
97
z09
0.10
784
0.00
13
0.29
232
0.00
39
4.34
243
0.06
17
0.08
335
0.00
13
1763
22
16
53
20
1702
12
16
18
24
94z1
0 0.
1268
4 0.
0017
0.
2526
9 0.
0034
4.
4141
5 0.
0660
0.
0749
5 0.
0014
20
55
23
1452
18
17
15
12
1461
26
71
Z11
0.10
576
0.00
13
0.28
344
0.00
39
4.13
223
0.05
95
0.07
552
0.00
11
1728
22
16
09
19
1661
12
14
72
21
93
-78-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
B
AC
41
sess
ion
2 (c
ontin
ued)
Z12
0.10
417
0.00
13
0.30
358
0.00
44
4.35
752
0.06
71
0.06
555
0.00
11
1700
23
17
09
22
1704
13
12
83
21
101
Z13
0.10
863
0.00
12
0.22
023
0.00
29
3.29
796
0.04
52
0.04
359
0.00
06
1777
20
12
83
15
1481
11
86
2 11
72
Z14
0.10
603
0.00
13
0.21
831
0.00
31
3.19
122
0.04
77
0.03
948
0.00
07
1732
22
12
73
16
1455
12
78
3 13
73
Z15
0.10
493
0.00
13
0.30
840
0.00
41
4.46
071
0.06
32
0.08
799
0.00
13
1713
22
17
33
20
1724
12
17
05
24
101
Z16
0.10
557
0.00
12
0.32
641
0.00
44
4.74
991
0.06
63
0.09
171
0.00
13
1724
21
18
21
21
1776
12
17
74
24
106
Z17
0.10
612
0.00
16
0.28
770
0.00
41
4.20
876
0.07
00
0.07
337
0.00
11
1734
27
16
30
21
1676
14
14
31
20
94Z1
8 0.
1086
6 0.
0015
0.
0960
3 0.
0013
1.
4386
0 0.
0219
0.
0427
8 0.
0007
17
77
24
591
8 90
5 9
847
14
33Z1
9 0.
1050
0 0.
0012
0.
3187
8 0.
0042
4.
6146
5 0.
0635
0.
0868
9 0.
0013
17
14
21
1784
21
17
52
11
1684
23
10
4Z2
0 0.
1040
1 0.
0012
0.
2772
5 0.
0037
3.
9752
7 0.
0555
0.
0810
4 0.
0011
16
97
22
1578
18
16
29
11
1575
21
93
Z21
0.10
627
0.00
12
0.31
301
0.00
42
4.58
372
0.06
36
0.08
704
0.00
12
1736
20
17
56
20
1746
12
16
87
21
101
Z22
0.10
575
0.00
13
0.29
073
0.00
43
4.23
777
0.06
64
0.07
355
0.00
11
1727
22
16
45
21
1681
13
14
34
22
95Z2
3 0.
1057
9 0.
0013
0.
3109
7 0.
0042
4.
5343
5 0.
0678
0.
0845
4 0.
0013
17
28
23
1746
21
17
37
12
1640
25
10
1Z2
4 0.
1121
2 0.
0014
0.
2984
5 0.
0044
4.
6109
7 0.
0733
0.
0788
3 0.
0014
18
34
23
1684
22
17
51
13
1534
26
92
Z25
0.10
640
0.00
12
0.30
833
0.00
41
4.52
234
0.06
23
0.08
450
0.00
11
1739
20
17
33
20
1735
11
16
40
20
100
Z26
0.10
918
0.00
13
0.29
061
0.00
38
4.37
361
0.06
06
0.08
338
0.00
11
1786
21
16
45
19
1707
11
16
19
20
92Z2
7 0.
1081
9 0.
0015
0.
2289
5 0.
0034
3.
4163
6 0.
0567
0.
0631
8 0.
0013
17
69
25
1329
18
15
08
13
1238
24
75
Z28
0.12
320
0.00
15
0.11
619
0.00
16
1.97
337
0.02
82
0.03
834
0.00
06
2003
21
70
9 9
1107
10
76
1 11
35
Z29
0.10
570
0.00
14
0.30
008
0.00
44
4.37
043
0.07
13
0.07
772
0.00
13
1727
24
16
92
22
1707
13
15
13
24
98Z3
0 0.
1077
6 0.
0017
0.
2821
2 0.
0046
4.
1931
8 0.
0787
0.
0622
8 0.
0018
17
62
29
1602
23
16
73
15
1221
34
91
Z31
0.10
708
0.00
12
0.30
154
0.00
40
4.45
145
0.06
21
0.08
156
0.00
10
1750
21
16
99
20
1722
12
15
85
19
97Z3
2 0.
1045
9 0.
0012
0.
2983
4 0.
0039
4.
3018
7 0.
0580
0.
0785
4 0.
0010
17
07
20
1683
19
16
94
11
1528
18
99
Z33
0.10
537
0.00
11
0.30
297
0.00
40
4.40
117
0.05
82
0.07
865
0.00
09
1721
19
17
06
20
1713
11
15
30
17
99Z3
4 0.
1025
8 0.
0013
0.
3000
2 0.
0043
4.
2430
4 0.
0649
0.
0693
8 0.
0010
16
71
22
1691
22
16
82
13
1356
19
10
1Z3
5 0.
1124
2 0.
0012
0.
2978
2 0.
0039
4.
6154
4 0.
0607
0.
0865
1 0.
0010
18
39
19
1681
19
17
52
11
1677
19
91
Z36
0.10
868
0.00
13
0.22
354
0.00
33
3.34
858
0.05
12
0.04
948
0.00
06
1777
22
13
01
17
1493
12
97
6 12
73
Z37
0.10
386
0.00
12
0.31
105
0.00
42
4.45
437
0.06
21
0.07
769
0.00
10
1694
20
17
46
21
1723
12
15
12
18
103
Z38
0.10
542
0.00
11
0.30
131
0.00
41
4.37
954
0.06
03
0.07
414
0.00
09
1722
20
16
98
20
1709
11
14
46
17
99Z3
9 0.
1048
6 0.
0011
0.
3071
8 0.
0042
4.
4410
3 0.
0609
0.
0807
5 0.
0010
17
12
19
1727
21
17
20
11
1570
19
10
1Z4
0 0.
1057
4 0.
0013
0.
3071
3 0.
0042
4.
4776
8 0.
0664
0.
0756
6 0.
0009
17
27
22
1727
21
17
27
12
1474
17
10
0Z4
1 0.
1100
3 0.
0013
0.
2348
3 0.
0033
3.
5621
8 0.
0523
0.
0738
0 0.
0010
18
00
21
1360
17
15
41
12
1439
19
76
Z42
0.10
415
0.00
11
0.30
472
0.00
41
4.37
523
0.05
97
0.08
853
0.00
12
1699
20
17
15
20
1708
11
17
15
22
101
Z43
0.10
524
0.00
12
0.25
387
0.00
34
3.68
331
0.05
16
0.07
426
0.00
10
1719
20
14
58
18
1568
11
14
48
20
85Z4
4 0.
1057
1 0.
0011
0.
2889
4 0.
0039
4.
2105
3 0.
0578
0.
0776
7 0.
0011
17
27
20
1636
20
16
76
11
1512
20
95
Z45
0.10
533
0.00
13
0.28
593
0.00
40
4.15
217
0.06
23
0.08
289
0.00
15
1720
23
16
21
20
1665
12
16
10
27
94Z4
6 0.
1074
9 0.
0012
0.
2393
1 0.
0034
3.
5467
0 0.
0513
0.
0669
4 0.
0009
17
57
21
1383
17
15
38
11
1310
18
79
Z47
0.10
549
0.00
13
0.29
526
0.00
41
4.29
393
0.06
29
0.08
261
0.00
13
1723
22
16
68
20
1692
12
16
04
24
97Z4
8 0.
1066
7 0.
0013
0.
3008
7 0.
0041
4.
4247
2 0.
0656
0.
0858
0 0.
0012
17
43
22
1696
21
17
17
12
1664
22
97
Z49
0.10
588
0.00
13
0.30
695
0.00
42
4.48
110
0.06
62
0.08
786
0.00
15
1730
22
17
26
21
1728
12
17
02
27
100
Z50
0.11
175
0.00
13
0.19
017
0.00
28
2.93
197
0.04
51
0.04
884
0.00
08
1828
21
11
22
15
1390
12
96
4 15
61
Z51
0.10
425
0.00
15
0.30
310
0.00
43
4.35
623
0.07
03
0.08
602
0.00
15
1701
25
17
07
21
1704
13
16
68
28
100
Z52
0.10
554
0.00
13
0.28
520
0.00
46
4.15
453
0.06
76
0.04
780
0.00
14
1724
22
16
18
23
1665
13
94
4 28
94
Z53
0.10
628
0.00
12
0.30
356
0.00
42
4.44
784
0.06
37
0.08
622
0.00
13
1737
20
17
09
21
1721
12
16
72
24
98Z5
4 0.
1058
6 0.
0012
0.
3330
7 0.
0046
4.
8614
5 0.
0693
0.
0925
0 0.
0014
17
29
20
1853
22
17
96
12
1788
26
10
7Z5
5 0.
1095
9 0.
0016
0.
1916
9 0.
0028
2.
8963
3 0.
0476
0.
0859
5 0.
0015
17
93
26
1131
15
13
81
12
1667
28
63
Z56
0.10
484
0.00
11
0.29
464
0.00
41
4.25
899
0.06
05
0.08
011
0.00
12
1712
20
16
65
20
1686
12
15
58
22
97
-79-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
B
AC
41
sess
ion
2 (c
ontin
ued)
Z57
0.10
687
0.00
12
0.31
159
0.00
45
4.59
098
0.06
88
0.08
040
0.00
13
1747
21
17
49
22
1748
13
15
63
25
100
Z58
0.10
745
0.00
12
0.30
894
0.00
43
4.57
740
0.06
52
0.08
913
0.00
14
1757
20
17
36
21
1745
12
17
26
25
99Z5
9 0.
1056
1 0.
0012
0.
3117
5 0.
0043
4.
5392
1 0.
0669
0.
0843
9 0.
0012
17
25
21
1749
21
17
38
12
1638
22
10
1Z6
0 0.
1068
7 0.
0012
0.
3100
0 0.
0043
4.
5679
8 0.
0661
0.
0873
1 0.
0013
17
47
21
1741
21
17
43
12
1692
25
10
0
TAL
4Z1
0.
1064
6 0.
0011
3.
2691
8 0.
0414
0.
2227
3 0.
0028
0.
0694
0 0.
0007
17
40
19
1474
10
12
96
15
1356
13
75
Z2
0.10
547
0.00
14
4.42
015
0.06
95
0.30
400
0.00
43
0.09
771
0.00
16
1723
24
17
16
13
1711
21
18
84
29
99Z3
0.
1073
5 0.
0011
4.
4502
6 0.
0572
0.
3007
0 0.
0038
0.
0849
5 0.
0008
17
55
19
1722
11
16
95
19
1648
15
97
Z4
0.10
811
0.00
12
3.06
183
0.03
99
0.20
544
0.00
25
0.06
570
0.00
07
1768
20
14
23
10
1205
14
12
86
14
68Z5
0.
1135
4 0.
0020
2.
0816
8 0.
0393
0.
1329
8 0.
0019
0.
0479
4 0.
0007
18
57
31
1143
13
80
5 11
94
7 14
43
Z6
0.11
483
0.00
20
2.48
516
0.04
48
0.15
705
0.00
21
0.08
001
0.00
14
1877
30
12
68
13
940
12
1556
26
50
Z7
0.10
701
0.00
13
4.34
728
0.05
87
0.29
472
0.00
36
0.08
414
0.00
09
1749
21
17
02
11
1665
18
16
33
16
95Z8
0.
1034
0 0.
0013
3.
4992
0 0.
0496
0.
2455
3 0.
0031
0.
0736
3 0.
0009
16
86
22
1527
11
14
15
16
1436
17
84
Z9
0.11
600
0.00
17
2.70
045
0.04
31
0.16
892
0.00
22
0.03
563
0.00
04
1896
26
13
29
12
1006
12
70
8 9
53Z1
0 0.
1086
2 0.
0016
4.
2794
9 0.
0714
0.
2857
9 0.
0039
0.
0836
5 0.
0010
17
76
27
1689
14
16
21
19
1624
19
91
Z11
0.11
958
0.00
17
2.54
059
0.04
11
0.15
412
0.00
21
0.03
980
0.00
06
1950
25
12
84
12
924
12
789
11
47Z1
2 0.
1025
7 0.
0011
4.
0941
8 0.
0519
0.
2894
7 0.
0036
0.
0826
7 0.
0010
16
71
19
1653
10
16
39
18
1605
19
98
Z13
0.12
363
0.00
31
0.99
601
0.02
44
0.05
845
0.00
08
0.00
787
0.00
04
2009
44
70
2 12
36
6 5
158
7 18
Z14
0.11
240
0.00
14
2.22
595
0.03
04
0.14
362
0.00
18
0.04
183
0.00
05
1839
22
11
89
10
865
10
828
10
47Z1
5 0.
1045
6 0.
0012
4.
1900
1 0.
0573
0.
2905
8 0.
0038
0.
0840
4 0.
0011
17
07
20
1672
11
16
44
19
1631
20
96
Z16
0.10
377
0.00
18
4.33
296
0.07
60
0.30
292
0.00
38
0.08
173
0.00
17
1693
31
17
00
14
1706
19
15
88
32
101
Z17
0.10
748
0.00
16
3.67
176
0.05
80
0.24
777
0.00
31
0.07
918
0.00
14
1757
27
15
65
13
1427
16
15
40
27
81Z1
8 0.
1056
1 0.
0012
4.
3375
4 0.
0593
0.
2978
5 0.
0038
0.
0843
7 0.
0009
17
25
21
1701
11
16
81
19
1637
17
97
Z19
0.11
030
0.00
20
1.07
765
0.02
03
0.07
087
0.00
10
0.04
387
0.00
09
1804
32
74
3 10
44
1 6
868
18
24Z2
0 0.
1132
6 0.
0018
2.
3021
3 0.
0400
0.
1474
0 0.
0020
0.
0590
2 0.
0012
18
52
29
1213
12
88
6 11
11
59
23
48Z2
1 0.
1060
4 0.
0012
4.
1879
8 0.
0577
0.
2865
0 0.
0038
0.
0849
1 0.
0009
17
32
20
1672
11
16
24
19
1647
16
94
Z22
0.10
687
0.00
16
4.40
660
0.07
71
0.29
921
0.00
43
0.07
965
0.00
11
1747
27
17
14
14
1687
21
15
49
20
97Z2
3 0.
1085
9 0.
0012
2.
5104
6 0.
0339
0.
1677
0 0.
0022
0.
0435
8 0.
0004
17
76
19
1275
10
99
9 12
86
2 9
56Z2
4 0.
1027
4 0.
0013
4.
1407
1 0.
0561
0.
2923
5 0.
0035
0.
0763
0 0.
0016
16
74
22
1662
11
16
53
18
1486
30
99
Z25
0.11
444
0.00
14
1.53
417
0.02
18
0.09
724
0.00
13
0.05
365
0.00
08
1871
22
94
4 9
598
7 10
56
16
32Z2
6 0.
1657
1 0.
0037
1.
6996
4 0.
0382
0.
0743
7 0.
0011
0.
0338
0 0.
0014
25
15
37
1008
14
46
2 7
672
27
18Z2
7 0.
1028
9 0.
0012
4.
0764
4 0.
0570
0.
2873
3 0.
0039
0.
0794
7 0.
0019
16
77
21
1650
11
16
28
19
1546
35
97
Z28
0.10
552
0.00
13
4.56
774
0.06
81
0.31
412
0.00
42
0.08
423
0.00
18
1723
23
17
43
12
1761
21
16
35
33
102
Z29
0.10
448
0.00
16
4.41
532
0.07
25
0.30
657
0.00
41
0.08
676
0.00
14
1705
27
17
15
14
1724
20
16
82
27
101
Z30
0.10
530
0.00
13
4.50
105
0.06
68
0.31
009
0.00
41
0.08
811
0.00
21
1720
23
17
31
12
1741
20
17
07
39
101
Z31
0.12
677
0.00
21
1.39
973
0.02
41
0.08
009
0.00
10
0.04
362
0.00
13
2054
29
88
9 10
49
7 6
863
25
24Z3
2 0.
1228
1 0.
0017
2.
6966
3 0.
0413
0.
1592
7 0.
0021
0.
0500
6 0.
0014
19
98
24
1328
11
95
3 12
98
7 26
48
Z33
0.10
099
0.00
13
3.02
788
0.04
61
0.21
752
0.00
30
0.06
929
0.00
18
1642
24
14
15
12
1269
16
13
54
34
77Z3
4 0.
1029
4 0.
0012
4.
2523
0 0.
0588
0.
2996
3 0.
0038
0.
0833
9 0.
0015
16
78
22
1684
11
16
90
19
1619
27
10
1Z3
5 0.
1036
4 0.
0012
3.
8816
3 0.
0542
0.
2717
1 0.
0036
0.
0784
7 0.
0019
16
90
21
1610
11
15
50
18
1527
35
92
Z36
0.13
741
0.00
16
7.36
729
0.10
12
0.38
899
0.00
50
0.11
574
0.00
34
2195
20
21
57
12
2118
23
22
14
61
97Z3
7 0.
1034
0 0.
0012
4.
1730
2 0.
0595
0.
2927
4 0.
0039
0.
1041
3 0.
0034
16
86
22
1669
12
16
55
19
2002
62
98
Z38
0.10
425
0.00
12
4.33
141
0.05
93
0.30
144
0.00
39
0.08
588
0.00
23
1701
21
16
99
11
1698
19
16
65
43
100
Z39
0.10
443
0.00
16
4.48
214
0.07
59
0.31
134
0.00
42
0.08
376
0.00
25
1704
28
17
28
14
1747
21
16
26
46
103
-80-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
Spo
t20
7 Pb/
206 P
b20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
207 Pb
/206 Pb
20
7 Pb/
235 U
206 P
b/23
8 U20
8 Pb/
232 Th
% C
onc
TA
L 4
(con
tinue
d)Z4
0 0.
1058
8 0.
0012
4.
4223
8 0.
0623
0.
3030
2 0.
0040
0.
0792
6 0.
0017
17
30
21
1717
12
17
06
20
1542
32
99
Z41
0.10
458
0.00
14
4.44
567
0.06
68
0.30
835
0.00
40
0.08
608
0.00
17
1707
24
17
21
12
1733
20
16
69
32
102
Z42
0.10
486
0.00
15
4.54
810
0.07
32
0.31
463
0.00
42
0.08
923
0.00
18
1712
26
17
40
13
1763
21
17
28
33
103
Z43
0.10
495
0.00
19
4.39
876
0.08
64
0.30
388
0.00
44
0.08
560
0.00
37
1713
33
17
12
16
1711
22
16
60
69
100
Z44
0.10
571
0.00
13
4.30
821
0.06
26
0.29
560
0.00
38
0.07
631
0.00
11
1727
23
16
95
12
1670
19
14
86
21
97Z4
5 0.
1029
4 0.
0014
4.
0692
9 0.
0619
0.
2867
3 0.
0037
0.
1158
3 0.
0053
16
78
25
1648
12
16
25
19
2215
96
97
Z46
0.10
433
0.00
12
4.34
643
0.05
97
0.30
218
0.00
39
0.08
026
0.00
12
1703
21
17
02
11
1702
19
15
61
22
100
Z47
0.10
157
0.00
16
3.87
523
0.06
69
0.27
672
0.00
40
0.07
505
0.00
34
1653
28
16
09
14
1575
20
14
63
63
95Z4
8 0.
1040
5 0.
0011
3.
7767
2 0.
0483
0.
2633
0 0.
0033
0.
0689
5 0.
0011
16
98
19
1588
10
15
07
17
1348
21
89
Z49
0.10
593
0.00
19
4.09
238
0.08
00
0.28
031
0.00
40
0.08
058
0.00
21
1731
33
16
53
16
1593
20
15
66
38
92Z5
0 0.
1050
2 0.
0011
4.
2485
7 0.
0554
0.
2934
7 0.
0037
0.
0823
7 0.
0012
17
15
20
1684
11
16
59
18
1600
23
97
Z51
0.10
477
0.00
11
4.48
646
0.05
79
0.31
064
0.00
39
0.08
835
0.00
13
1710
20
17
29
11
1744
19
17
11
25
102
Z52
0.10
853
0.00
12
4.66
910
0.06
00
0.31
206
0.00
39
0.09
853
0.00
15
1775
19
17
62
11
1751
19
19
00
28
99Z5
3 0.
1038
9 0.
0012
4.
2605
2 0.
0563
0.
2974
9 0.
0038
0.
0868
6 0.
0013
16
95
20
1686
11
16
79
19
1684
25
99
Z54
0.09
871
0.00
19
3.74
315
0.07
09
0.27
512
0.00
39
0.07
660
0.00
56
1600
35
15
81
15
1567
20
14
92
105
98Z5
5 0.
1050
8 0.
0013
4.
4226
8 0.
0602
0.
3053
4 0.
0039
0.
0879
7 0.
0025
17
16
22
1717
11
17
18
19
1704
46
10
0
TAL
4 se
ssio
n 2
Z01
0.10
440
0.00
12
0.29
460
0.00
37
4.23
880
0.05
52
0.12
019
0.00
28
1704
21
16
65
18
1682
11
22
94
50
98Z0
2 0.
1028
9 0.
0012
0.
3036
5 0.
0038
4.
3058
4 0.
0565
0.
0971
1 0.
0022
16
77
21
1709
19
16
95
11
1873
41
10
2Z0
3 0.
1023
8 0.
0011
0.
2986
1 0.
0037
4.
2136
3 0.
0548
0.
1321
7 0.
0060
16
68
20
1684
18
16
77
11
2509
10
8 10
1Z0
4 0.
1024
4 0.
0013
0.
2977
1 0.
0037
4.
2031
0 0.
0578
0.
0881
0 0.
0015
16
69
23
1680
19
16
75
11
1707
28
10
1Z0
5 0.
1018
5 0.
0013
0.
2747
2 0.
0036
3.
8571
3 0.
0551
0.
0575
4 0.
0016
16
58
23
1565
18
16
05
12
1131
31
94
Z06
0.10
192
0.00
12
0.29
326
0.00
37
4.11
964
0.05
64
0.10
731
0.00
48
1659
22
16
58
19
1658
11
20
60
88
100
Z07
0.10
875
0.00
13
0.27
180
0.00
35
4.07
464
0.05
59
0.08
150
0.00
11
1779
21
15
50
18
1649
11
15
84
20
87Z0
8 0.
1013
3 0.
0011
0.
2811
1 0.
0035
3.
9263
8 0.
0497
0.
0858
1 0.
0015
16
49
20
1597
18
16
19
10
1664
27
97
Z09
0.10
790
0.00
14
0.24
052
0.00
33
3.57
758
0.05
34
0.06
587
0.00
11
1764
23
13
89
17
1545
12
12
89
20
79Z1
0 0.
1022
9 0.
0015
0.
2861
9 0.
0037
4.
0355
9 0.
0624
0.
0822
6 0.
0056
16
66
26
1623
19
16
41
13
1598
10
5 97
Z11
0.10
371
0.00
12
0.25
996
0.00
34
3.71
671
0.05
13
0.07
453
0.00
12
1692
22
14
90
17
1575
11
14
53
22
88Z1
2 0.
1042
4 0.
0013
0.
2728
1 0.
0037
3.
9205
2 0.
0564
0.
0842
2 0.
0019
17
01
22
1555
19
16
18
12
1634
36
91
Z13
0.10
315
0.00
11
0.29
016
0.00
36
4.12
634
0.05
26
0.08
618
0.00
15
1682
20
16
42
18
1660
10
16
71
29
98Z1
4 0.
1048
0 0.
0012
0.
2835
5 0.
0034
4.
0975
4 0.
0518
0.
0838
9 0.
0014
17
11
20
1609
17
16
54
10
1628
26
94
Z15
0.10
769
0.00
13
0.30
178
0.00
42
4.47
977
0.06
73
0.08
632
0.00
18
1761
22
17
00
21
1727
12
16
73
33
97Z1
6 0.
1038
3 0.
0011
0.
3003
9 0.
0037
4.
3002
5 0.
0543
0.
0969
8 0.
0019
16
94
20
1693
18
16
93
10
1871
35
10
0Z1
7 0.
1060
4 0.
0012
0.
2990
7 0.
0040
4.
3723
1 0.
0601
0.
0880
0 0.
0018
17
32
20
1687
20
17
07
11
1705
33
97
Z18
0.10
395
0.00
12
0.25
550
0.00
32
3.66
178
0.04
82
0.05
284
0.00
14
1696
20
14
67
17
1563
11
10
41
26
86Z1
9 0.
1061
9 0.
0036
0.
2844
3 0.
0049
4.
1644
5 0.
1370
0.
0818
6 0.
0018
17
35
60
1614
25
16
67
27
1590
34
93
Z20
0.10
662
0.00
14
0.30
480
0.00
39
4.48
036
0.06
34
0.08
766
0.00
16
1742
23
17
15
19
1727
12
16
98
31
98*
indi
cate
s met
amor
phic
zirc
on.
-81-
Chapter 3 Supplementary Material
Supp
lem
enta
ry T
able
2. U
-Pb
mon
azite
dat
a fr
om th
e Fo
wle
r Dom
ain
Rad
ioge
nic
Rat
ios
Age
(Ma)
S
pot
207 P
b/20
6 Pb
206 P
b/23
8 U20
7 Pb/
235 U
207 Pb
/206 Pb
20
6 Pb/
238 U
207 P
b/23
5 U%
Con
B
AC
18M
10.
0986
30.
0011
0.29
168
0.00
383.
9742
10.
0523
1598
2016
5019
1629
1199
M2
0.10
223
0.00
230.
3342
90.
0054
4.72
004
0.10
8316
6541
1859
2617
7119
97M
30.
1053
40.
0011
0.31
967
0.00
424.
6517
70.
0609
1720
1917
8820
1759
1195
M4
0.10
309
0.00
110.
3030
30.
0040
4.31
522
0.05
6116
8119
1706
2016
9611
98M
50.
1024
40.
0010
0.31
024
0.00
404.
3903
20.
0567
1669
1917
4220
1711
1197
M6
0.10
486
0.00
120.
3209
90.
0042
4.64
990
0.06
3417
1220
1795
2117
5811
97M
70.
1068
70.
0016
0.30
522
0.00
434.
5066
20.
0757
1747
2817
1721
1732
1499
M8
0.10
697
0.00
180.
3128
80.
0045
4.62
412
0.08
2317
4830
1755
2217
5415
93M
90.
1040
60.
0014
0.31
055
0.00
434.
4643
50.
0695
1698
2517
4321
1724
1397
M10
0.10
526
0.00
120.
3047
70.
0041
4.43
258
0.06
0717
1920
1715
2017
1811
100
M11
0.10
312
0.00
110.
3544
70.
0047
5.04
903
0.06
7416
8119
1956
2218
2811
99M
120.
1039
60.
0011
0.30
288
0.00
404.
3491
90.
0575
1696
1917
0620
1703
1198
M13
0.10
751
0.00
110.
3221
80.
0043
4.78
443
0.06
3617
5819
1800
2117
8211
100
M14
0.10
573
0.00
110.
3296
40.
0044
4.81
412
0.06
4317
2719
1837
2117
8711
98M
150.
1031
20.
0010
0.31
999
0.00
424.
5580
00.
0591
1681
1817
9021
1742
1198
M16
0.10
268
0.00
150.
3224
20.
0045
4.57
212
0.07
2616
7326
1802
2217
4413
97M
170.
1151
80.
0013
0.33
059
0.00
445.
2596
90.
0720
1883
2018
4121
1862
1210
1M
180.
1026
20.
0010
0.32
313
0.00
434.
5802
00.
0599
1672
1918
0521
1746
1110
0M
190.
1020
70.
0012
0.31
674
0.00
434.
4652
90.
0622
1662
2117
7421
1725
1299
M20
0.10
549
0.00
130.
3209
50.
0044
4.67
628
0.06
8517
2323
1794
2117
6312
101
BA
C41
M1
0.10
214
0.00
110.
2926
60.
0038
4.12
897
0.05
5216
6320
1655
1916
6011
99M
20.
1022
80.
0011
0.28
824
0.00
384.
0725
80.
0537
1666
1916
3319
1649
1198
M3
0.10
171
0.00
110.
2921
30.
0038
4.10
458
0.05
4816
5620
1652
1916
5511
100
M4
0.10
199
0.00
100.
3005
00.
0039
4.23
377
0.05
3816
6118
1694
1916
8110
102
M5
0.10
131
0.00
100.
2985
20.
0039
4.17
764
0.05
3316
4818
1684
1916
7010
102
M6
0.10
125
0.00
100.
3004
70.
0039
4.20
265
0.05
3416
4718
1694
1916
7510
103
M7
0.10
088
0.00
110.
2917
10.
0038
4.06
530
0.05
4516
4020
1650
1916
4711
101
M8
0.10
308
0.00
110.
2985
80.
0039
4.25
187
0.05
5216
8019
1684
1916
8411
100
M9
0.10
206
0.00
100.
2957
20.
0039
4.16
982
0.05
3816
6219
1670
1916
6811
100
M10
0.10
045
0.00
110.
2938
80.
0039
4.07
851
0.05
4416
3320
1661
1916
5011
102
M11
0.10
244
0.00
100.
3026
50.
0040
4.28
258
0.05
5716
6918
1705
2016
9011
102
M12
0.10
258
0.00
100.
3037
10.
0040
4.30
387
0.05
6216
7118
1710
2016
9411
102
M13
0.10
230
0.00
110.
3067
40.
0041
4.33
466
0.05
8916
6620
1725
2017
0011
103
M14
0.10
284
0.00
110.
3024
90.
0040
4.29
729
0.05
6416
7619
1704
2016
9311
102
M15
0.10
300
0.00
100.
2966
20.
0039
4.22
043
0.05
5416
7919
1675
1916
7811
100
M16
0.10
272
0.00
100.
2949
10.
0039
4.18
436
0.05
4816
7419
1666
1916
7111
100
M17
0.10
245
0.00
100.
2977
80.
0039
4.21
426
0.05
5416
6919
1680
1916
7711
101
M18
0.10
305
0.00
110.
2960
00.
0039
4.21
289
0.05
5216
8019
1671
1916
7711
99M
190.
1015
30.
0011
0.29
153
0.00
394.
0886
30.
0552
1652
2016
4919
1652
1110
0M
200.
1032
40.
0011
0.30
053
0.00
404.
2857
10.
0562
1683
1916
9420
1691
1110
1M
210.
1017
20.
0011
0.29
220
0.00
384.
1062
40.
0547
1656
2016
5319
1656
1110
0M
220.
1026
10.
0011
0.29
617
0.00
394.
1984
80.
0555
1672
1916
7219
1674
1110
0M
230.
1021
50.
0010
0.29
629
0.00
384.
1815
90.
0537
1664
1916
7319
1670
1110
1M
240.
1029
10.
0011
0.30
298
0.00
404.
3076
40.
0584
1677
2017
0620
1695
1110
2M
250.
1033
10.
0011
0.28
244
0.00
374.
0312
50.
0536
1684
2016
0418
1641
1195
-82-
Chapter 3 Supplementary Material
Rad
ioge
nic
Rat
ios
Age
(Ma)
S
pot
207 P
b/20
6 Pb
206 P
b/23
8 U20
7 Pb/
235 U
207 Pb
/206 Pb
20
6 Pb/
238 U
207 P
b/23
5 U%
Con
M
260.
1026
40.
0011
0.29
305
0.00
374.
1555
00.
0533
1672
1916
5719
1665
1099
M27
0.10
283
0.00
110.
2933
10.
0037
4.16
733
0.05
3016
7619
1658
1916
6810
99M
280.
1005
40.
0011
0.27
946
0.00
353.
8817
10.
0511
1634
2015
8918
1610
1197
M29
0.10
165
0.00
110.
2851
80.
0036
4.00
500
0.05
2516
5520
1617
1816
3511
98M
300.
1019
60.
0011
0.28
524
0.00
364.
0181
90.
0525
1660
2016
1818
1638
1197
CO
L20D
M
10.
1043
70.
0011
0.30
711
0.00
404.
4272
90.
0581
1703
1917
2720
1718
1199
M2
0.10
315
0.00
110.
3024
10.
0040
4.30
852
0.05
6116
8219
1703
2016
9511
100
M3
0.10
206
0.00
110.
3017
10.
0040
4.25
291
0.05
6216
6219
1700
2016
8411
99M
40.
1026
60.
0011
0.31
147
0.00
414.
4165
80.
0578
1673
1917
4820
1716
1198
M5
0.10
318
0.00
110.
3022
60.
0040
4.30
759
0.05
7616
8220
1703
2016
9511
100
M6
0.10
309
0.00
100.
3009
30.
0040
4.28
506
0.05
5616
8118
1696
2016
9111
100
M7
0.10
242
0.00
110.
3043
00.
0041
4.30
464
0.05
8616
6820
1713
2016
9411
99M
80.
1035
80.
0012
0.30
861
0.00
424.
4152
60.
0616
1689
2117
3420
1715
1299
M9
0.10
365
0.00
110.
3070
70.
0041
4.39
617
0.05
8416
9019
1726
2017
1211
99M
100.
1039
20.
0011
0.30
720
0.00
414.
4097
00.
0596
1695
2017
2720
1714
1199
M11
0.10
307
0.00
110.
3092
70.
0041
4.40
309
0.05
8816
8019
1737
2017
1311
99M
120.
1050
90.
0011
0.30
995
0.00
414.
4995
10.
0593
1716
1917
4120
1731
1199
M13
0.10
303
0.00
110.
3225
70.
0043
4.59
041
0.06
2616
7920
1802
2117
4811
97M
140.
1036
20.
0011
0.31
373
0.00
424.
4899
40.
0597
1690
1917
5920
1729
1198
M15
0.10
489
0.00
160.
3031
00.
0043
4.39
120
0.07
3517
1227
1707
2117
1114
100
M16
0.10
386
0.00
110.
3041
30.
0041
4.36
285
0.05
9316
9420
1712
2017
0511
100
M17
0.10
269
0.00
100.
3047
00.
0040
4.32
165
0.05
6716
7318
1715
2016
9811
99M
180.
1042
50.
0011
0.30
350
0.00
404.
3699
20.
0575
1701
1917
0920
1707
1110
0M
190.
1044
60.
0011
0.30
835
0.00
414.
4486
00.
0588
1705
1917
3320
1721
1199
M20
0.10
585
0.00
120.
2950
40.
0040
4.31
336
0.06
1117
2921
1667
2016
9612
102
TAL2
0M
10.
1031
30.
0013
0.29
468
0.00
394.
1982
20.
0608
1681
2316
6519
1674
1210
0M
20.
1020
70.
0013
0.29
305
0.00
394.
1315
60.
0597
1662
2316
5719
1661
1210
0M
30.
1053
20.
0015
0.29
696
0.00
414.
3205
50.
0693
1720
2616
7620
1697
1310
0M
40.
1021
40.
0012
0.29
859
0.00
394.
2130
60.
0582
1663
2116
8419
1677
1110
0M
50.
1023
90.
0012
0.28
515
0.00
374.
0338
80.
0551
1668
2116
1719
1641
1110
0M
60.
1024
40.
0011
0.29
600
0.00
384.
1887
80.
0546
1669
1916
7219
1672
1110
0M
70.
1022
50.
0011
0.29
465
0.00
384.
1639
60.
0551
1665
2016
6519
1667
1110
0M
80.
1048
20.
0014
0.29
116
0.00
394.
2161
00.
0639
1711
2416
4720
1677
1210
1M
90.
1035
50.
0013
0.30
219
0.00
404.
3224
90.
0621
1689
2217
0220
1698
1210
0M
100.
1020
10.
0012
0.29
102
0.00
384.
1007
90.
0563
1661
2116
4719
1655
1110
0M
110.
1045
90.
0014
0.29
542
0.00
404.
2670
90.
0661
1707
2516
6920
1687
1310
0M
120.
1034
00.
0013
0.29
598
0.00
394.
2274
70.
0614
1686
2316
7120
1679
1210
0M
130.
1024
60.
0011
0.29
478
0.00
384.
1720
10.
0543
1669
1916
6519
1669
1110
0M
140.
1024
80.
0011
0.29
400
0.00
384.
1616
50.
0541
1670
1916
6219
1667
1110
0M
150.
1023
00.
0011
0.29
576
0.00
384.
1795
60.
0546
1666
1916
7019
1670
1110
1M
160.
1023
00.
0011
0.29
665
0.00
384.
1921
50.
0542
1666
1916
7519
1673
1110
0M
170.
1025
40.
0011
0.29
529
0.00
384.
1826
90.
0546
1671
1916
6819
1671
1110
0M
180.
1014
40.
0011
0.29
337
0.00
384.
1110
70.
0533
1651
1916
5819
1657
1110
1M
190.
1024
60.
0011
0.29
733
0.00
384.
2085
60.
0547
1669
1916
7819
1676
1110
2M
200.
1025
80.
0013
0.29
603
0.00
394.
1951
20.
0613
1671
2316
7220
1673
1210
1
-83-
Chapter 3 Supplementary Material
Sup
plem
enta
ry T
able
3.
Hf
isot
opic
dat
a Blic
hert
-Tof
t et
al,
1997
(1.
93x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )Biz
zarr
o et
al.,
200
3 (1
.983
x10-1
1 )
Ana
lysi
s 17
6 Hf/17
7 Hf
1 S
.D.
176 Lu
/177 H
f 17
6 Yb/17
7 Hf
AG
EH
f iH
f2S
D
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
C
OL2
0D1-
07
0.28
1710
0.
0000
34
0.00
0710
0.
0187
82
1872
0.
2816
84
4.7
2.38
2.
07
2.21
0.
2816
85
3.3
2.15
2.
33
0.28
1683
5.
9 2.
02
2.12
C
OL2
0D1-
12
0.28
1601
0.
0000
20
0.00
0462
0.
0125
70
1768
0.
2815
85
-1.2
1.
40
2.20
2.
50
0.28
1586
-2
.6
2.28
2.
63
0.28
1585
-0
.1
2.15
2.
40
CO
L20D
1-13
0.
2817
01
0.00
0016
0.
0010
88
0.02
7873
19
52
0.28
1659
5.
8 1.
12
2.11
2.
21
0.28
1661
4.
3 2.
18
2.33
0.
2816
58
7.0
2.05
2.
12
CO
L20D
1-17
0.
2815
77
0.00
0016
0.
0009
56
0.02
6964
20
67
0.28
1538
4.
2 1.
12
2.26
2.
40
0.28
1539
2.
6 2.
34
2.53
0.
2815
37
5.5
2.20
2.
30
CO
L20D
1-16
0.
2816
40
0.00
0014
0.
0006
48
0.01
7734
18
37
0.28
1617
1.
5 0.
98
2.16
2.
38
0.28
1617
0.
1 2.
24
2.51
0.
2816
16
2.7
2.11
2.
29
CO
L20D
1-19
0.
2816
53
0.00
0011
0.
0010
20
0.02
7623
17
45
0.28
1618
-0
.6
0.77
2.
17
2.44
0.
2816
19
-1.9
2.
24
2.57
0.
2816
17
0.5
2.11
2.
35
CO
L20D
1-20
0.
2816
84
0.00
0021
0.
0007
46
0.01
9943
17
89
0.28
1658
1.
9 1.
47
2.11
2.
33
0.28
1659
0.
5 2.
18
2.45
0.
2816
57
3.0
2.05
2.
23
CO
L20D
1-21
0.
2816
95
0.00
0012
0.
0008
50
0.02
1709
19
55
0.28
1662
5.
9 0.
84
2.10
2.
20
0.28
1663
4.
4 2.
18
2.32
0.
2816
61
7.2
2.05
2.
11
CO
L20D
1-22
a 0.
2817
07
0.00
0019
0.
0014
29
0.04
3272
19
76
0.28
1651
6.
0 1.
33
2.12
2.
21
0.28
1653
4.
5 2.
19
2.33
0.
2816
50
7.3
2.06
2.
12
CO
L20D
1-22
b 0.
2816
24
0.00
0026
0.
0002
14
0.00
6210
19
76
0.28
1616
4.
8 1.
82
2.16
2.
29
0.28
1616
3.
2 2.
24
2.42
0.
2816
15
6.1
2.10
2.
19
CO
L20D
1-24
0.
2816
69
0.00
0012
0.
0007
34
0.02
0215
17
69
0.28
1644
0.
9 0.
84
2.13
2.
37
0.28
1644
-0
.5
2.20
2.
49
0.28
1643
2.
0 2.
07
2.28
C
OL2
0D1-
25
0.28
1629
0.
0000
14
0.00
0606
0.
0155
38
1698
0.
2816
09
-2.0
0.
98
2.18
2.
50
0.28
1610
-3
.3
2.25
2.
62
0.28
1608
-0
.9
2.12
2.
40
CO
L20D
1-28
0.
2816
60
0.00
0023
0.
0008
31
0.02
5168
19
62
0.28
1628
4.
9 1.
61
2.15
2.
27
0.28
1629
3.
3 2.
22
2.40
0.
2816
27
6.1
2.09
2.
18
CO
L20D
2-31
0.
2816
12
0.00
0012
0.
0008
45
0.02
3362
18
36
0.28
1582
0.
3 0.
84
2.21
2.
46
0.28
1583
-1
.2
2.29
2.
59
0.28
1581
1.
4 2.
15
2.36
C
OL2
0D2-
33
0.28
1683
0.
0000
19
0.00
0682
0.
0177
08
1707
0.
2816
60
0.0
1.33
2.
11
2.38
0.
2816
61
-1.3
2.
18
2.50
0.
2816
60
1.1
2.05
2.
28
CO
L20D
2-34
0.
2816
39
0.00
0014
0.
0007
55
0.02
1398
17
99
0.28
1612
0.
5 0.
98
2.17
2.
42
0.28
1613
-0
.9
2.25
2.
54
0.28
1612
1.
6 2.
11
2.32
C
OL2
0D2-
36
0.28
1578
0.
0000
23
0.00
0986
0.
0270
58
1749
0.
2815
44
-3.1
1.
61
2.27
2.
60
0.28
1545
-4
.5
2.34
2.
73
0.28
1543
-2
.0
2.20
2.
50
CO
L20D
2-37
0.
2810
86
0.00
0018
0.
0006
50
0.01
6833
28
14
0.28
1050
4.
6 1.
26
2.89
2.
94
0.28
1051
2.
4 2.
99
3.11
0.
2810
49
6.5
2.81
2.
81
CO
L20D
2-39
0.
2817
65
0.00
0019
0.
0009
03
0.02
3428
17
30
0.28
1734
3.
2 1.
33
2.01
2.
20
0.28
1735
1.
8 2.
08
2.31
0.
2817
33
4.3
1.96
2.
11
CO
L20D
2-40
0.
2809
37
0.00
0015
0.
0006
45
0.01
7581
31
31
0.28
0897
6.
9 1.
05
3.08
3.
05
0.28
0898
4.
4 3.
19
3.23
0.
2808
96
8.9
3.00
2.
91
CO
L20D
2-42
0.
2815
96
0.00
0013
0.
0009
41
0.02
6535
17
87
0.28
1563
-1
.6
0.91
2.
24
2.54
0.
2815
64
-2.9
2.
32
2.66
0.
2815
62
-0.4
2.
18
2.44
C
OL2
0D2-
43
0.28
1701
0.
0000
24
0.00
0830
0.
0225
13
1730
0.
2816
73
1.0
1.68
2.
09
2.33
0.
2816
74
-0.3
2.
17
2.45
0.
2816
72
2.1
2.04
2.
24
CO
L20D
2-44
0.
2816
37
0.00
0015
0.
0001
67
0.00
4867
16
89
0.28
1631
-1
.4
1.05
2.
14
2.45
0.
2816
32
-2.8
2.
22
2.58
0.
2816
31
-0.4
2.
08
2.36
C
OL2
0D2-
47
0.28
1751
0.
0000
35
0.00
1461
0.
0391
99
1776
0.
2817
00
3.0
2.45
2.
06
2.24
0.
2817
02
1.7
2.13
2.
36
0.28
1699
4.
1 2.
01
2.15
C
OL2
0D2-
48
0.28
1127
0.
0000
20
0.00
0761
0.
0224
92
2378
0.
2810
91
-4.3
1.
40
2.84
3.
16
0.28
1092
-6
.2
2.94
3.
33
0.28
1090
-2
.8
2.77
3.
03
CO
L20D
2-51
0.
2811
00
0.00
0020
0.
0006
13
0.01
6637
28
41
0.28
1065
5.
9 1.
40
2.87
2.
89
0.28
1067
3.
6 2.
97
3.06
0.
2810
64
7.7
2.79
2.
76
CO
L20D
2-52
0.
2816
53
0.00
0017
0.
0008
47
0.02
1767
17
12
0.28
1625
-1
.1
1.19
2.
16
2.45
0.
2816
26
-2.5
2.
23
2.57
0.
2816
24
-0.1
2.
10
2.36
C
OL2
0D2-
54
0.28
1588
0.
0000
11
0.00
0536
0.
0150
54
1712
0.
2815
70
-3.1
0.
77
2.23
2.
57
0.28
1571
-4
.4
2.30
2.
70
0.28
1569
-2
.0
2.17
2.
47
CO
L20D
2-55
0.
2816
77
0.00
0015
0.
0008
04
0.02
2428
18
36
0.28
1648
2.
6 1.
05
2.12
2.
32
0.28
1649
1.
2 2.
20
2.44
0.
2816
47
3.8
2.07
2.
22
CO
L20D
2-56
0.
2816
33
0.00
0020
0.
0008
84
0.02
3029
17
84
0.28
1602
-0
.3
1.40
2.
19
2.45
0.
2816
03
-1.6
2.
26
2.58
0.
2816
01
0.9
2.13
2.
36
CO
L20D
2-57
0.
2816
65
0.00
0026
0.
0008
60
0.02
3749
17
83
0.28
1635
0.
9 1.
82
2.14
2.
38
0.28
1636
-0
.5
2.22
2.
50
0.28
1634
2.
0 2.
09
2.29
C
OL2
0D2-
58
0.28
1586
0.
0000
13
0.00
0736
0.
0183
92
1676
0.
2815
62
-4.2
0.
91
2.24
2.
61
0.28
1563
-5
.5
2.32
2.
74
0.28
1561
-3
.2
2.18
2.
51
CO
L20D
2-60
0.
2816
03
0.00
0013
0.
0007
86
0.02
0179
17
07
0.28
1577
-3
.0
0.91
2.
22
2.56
0.
2815
78
-4.3
2.
30
2.69
0.
2815
76
-1.9
2.
16
2.46
BA
C41
-02
0.28
1571
0.
0000
18
0.00
1344
0.
0381
87
1698
0.
2815
26
-5.0
1.
26
2.30
2.
68
0.28
1528
-6
.3
2.38
2.
80
0.28
1525
-3
.9
2.23
2.
58
BA
C41
-03
0.28
1635
0.
0000
27
0.00
2774
0.
0911
78
1725
0.
2815
41
-3.8
1.
89
2.30
2.
62
0.28
1544
-5
.0
2.38
2.
75
0.28
1538
-2
.8
2.24
2.
53
BA
C41
-05
0.28
1562
0.
0000
21
0.00
1293
0.
0347
22
1721
0.
2815
18
-4.7
1.
47
2.30
2.
68
0.28
1520
-6
.0
2.39
2.
81
0.28
1517
-3
.6
2.24
2.
58
-84-
Chapter 3 Supplementary MaterialBlic
hert
-Tof
t et
al,
1997
(1.
93x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )Biz
zarr
o et
al.,
200
3 (1
.983
x10-1
1 )
Ana
lysi
s 17
6 Hf/17
7 Hf
1 S
.D.
176 Lu
/177 H
f 17
6 Yb/17
7 Hf
AG
EH
f iH
f2S
D
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
B
AC
41-0
7 0.
2816
85
0.00
0023
0.
0018
98
0.05
2416
17
27
0.28
1621
-0
.9
1.61
2.
18
2.45
0.
2816
23
-2.2
2.
25
2.57
0.
2816
19
0.1
2.12
2.
36
BA
C41
-08
0.28
1644
0.
0000
22
0.00
1959
0.
0582
21
1732
0.
2815
77
-2.3
1.
54
2.23
2.
54
0.28
1580
-3
.6
2.31
2.
66
0.28
1576
-1
.3
2.17
2.
45
BA
C41
-09
0.28
1710
0.
0000
24
0.00
0693
0.
0179
68
1722
0.
2816
87
1.3
1.68
2.
07
2.31
0.
2816
87
0.0
2.15
2.
43
0.28
1686
2.
4 2.
02
2.22
B
AC
41-1
1 0.
2816
91
0.00
0028
0.
0032
18
0.09
8705
17
18
0.28
1582
-2
.5
1.96
2.
25
2.54
0.
2815
86
-3.7
2.
32
2.66
0.
2815
79
-1.5
2.
19
2.45
B
AC
41-1
5 0.
2816
91
0.00
0025
0.
0014
43
0.04
0903
17
33
0.28
1642
0.
0 1.
75
2.14
2.
40
0.28
1644
-1
.3
2.22
2.
52
0.28
1641
1.
0 2.
08
2.31
B
AC
41-1
8 0.
2816
57
0.00
0022
0.
0012
02
0.03
6601
17
43
0.28
1616
-0
.7
1.54
2.
17
2.45
0.
2816
17
-2.1
2.
25
2.57
0.
2816
15
0.4
2.11
2.
36
BA
C41
-20
0.28
1695
0.
0000
23
0.00
1326
0.
0371
89
1739
0.
2816
50
0.4
1.61
2.
13
2.38
0.
2816
51
-0.9
2.
20
2.50
0.
2816
48
1.5
2.07
2.
29
BA
C41
-21
0.28
1705
0.
0000
47
0.00
2339
0.
0670
97
1738
0.
2816
25
-0.5
3.
29
2.17
2.
43
0.28
1628
-1
.8
2.25
2.
55
0.28
1623
0.
5 2.
12
2.34
B
AC
41-2
2 0.
2816
33
0.00
0019
0.
0016
34
0.05
1950
17
22
0.28
1578
-2
.6
1.33
2.
23
2.55
0.
2815
80
-3.9
2.
31
2.67
0.
2815
76
-1.5
2.
17
2.45
B
AC
41-2
6 0.
2817
28
0.00
0015
0.
0009
34
0.02
7874
17
39
0.28
1696
2.
0 1.
05
2.06
2.
28
0.28
1697
0.
7 2.
14
2.40
0.
2816
95
3.1
2.01
2.
19
BA
C41
-28
0.28
1570
0.
0000
31
0.00
2189
0.
0716
57
1750
0.
2814
95
-4.9
2.
17
2.35
2.
71
0.28
1497
-6
.2
2.43
2.
84
0.28
1493
-3
.8
2.29
2.
61
BA
C41
-29
0.28
1781
0.
0000
21
0.00
1307
0.
0371
67
1715
0.
2817
37
2.9
1.47
2.
01
2.20
0.
2817
39
1.6
2.08
2.
32
0.28
1736
4.
0 1.
96
2.12
B
AC
41-3
1 0.
2816
68
0.00
0054
0.
0020
93
0.05
8775
17
27
0.28
1597
-1
.8
3.78
2.
21
2.50
0.
2815
99
-3.1
2.
29
2.62
0.
2815
95
-0.7
2.
15
2.41
B
AC
41-3
2 0.
2816
24
0.00
0046
0.
0027
45
0.07
9886
17
46
0.28
1530
-3
.7
3.22
2.
31
2.64
0.
2815
33
-5.0
2.
39
2.76
0.
2815
27
-2.7
2.
25
2.54
B
AC
41-3
3 0.
2818
16
0.00
0083
0.
0035
04
0.10
0363
17
28
0.28
1697
1.
8 5.
81
2.09
2.
28
0.28
1701
0.
6 2.
16
2.39
0.
2816
94
2.8
2.03
2.
20
BA
C41
-36
0.28
1705
0.
0000
27
0.00
3210
0.
1004
15
1760
0.
2815
94
-1.1
1.
89
2.23
2.
49
0.28
1598
-2
.3
2.30
2.
60
0.28
1591
-0
.1
2.17
2.
39
BA
C41
-40
0.28
1719
0.
0000
43
0.00
1038
0.
0281
72
1724
0.
2816
84
1.2
3.01
2.
08
2.31
0.
2816
85
-0.1
2.
15
2.43
0.
2816
83
2.3
2.03
2.
22
B
AC
18-1
0 0.
2816
45
0.00
0081
0.
0006
00
0.01
7785
17
45
0.28
1624
-0
.4
5.67
2.
15
2.43
0.
2816
25
-1.7
2.
23
2.55
0.
2816
24
0.7
2.10
2.
33
BA
C18
-16
0.28
1244
0.
0003
10
0.00
0926
0.
0268
36
1766
0.
2812
12
-14.
5 21
.70
2.70
3.
31
0.28
1213
-1
5.9
2.80
3.
46
0.28
1211
-1
3.4
2.63
3.
19
BA
C18
-27
0.28
1770
0.
0000
19
0.00
1119
0.
0314
36
1730
0.
2817
32
3.1
1.33
2.
02
2.20
0.
2817
33
1.8
2.09
2.
32
0.28
1731
4.
2 1.
96
2.12
B
AC
18-3
5 0.
2816
90
0.00
0017
0.
0012
12
0.03
3733
17
58
0.28
1648
0.
8 1.
19
2.13
2.
37
0.28
1650
-0
.6
2.20
2.
49
0.28
1647
1.
9 2.
07
2.28
B
AC
18-3
7 0.
2816
84
0.00
0021
0.
0006
07
0.01
4142
17
23
0.28
1663
0.
5 1.
47
2.10
2.
36
0.28
1664
-0
.8
2.18
2.
48
0.28
1663
1.
6 2.
05
2.27
B
AC
18-3
8 0.
2816
76
0.00
0014
0.
0013
99
0.04
2245
17
33
0.28
1628
-0
.5
0.98
2.
16
2.43
0.
2816
30
-1.8
2.
23
2.55
0.
2816
27
0.6
2.10
2.
34
BA
C18
-43
0.28
1720
0.
0000
15
0.00
1192
0.
0343
73
1719
0.
2816
80
1.0
1.05
2.
09
2.33
0.
2816
81
-0.3
2.
16
2.44
0.
2816
79
2.1
2.03
2.
24
TA
L4-0
2 0.
2819
79
0.00
0008
0.
0019
15
0.05
4919
17
23
0.28
1914
9.
4 0.
57
1.77
1.
81
0.28
1916
8.
1 1.
84
1.91
0.
2819
12
10.4
1.
73
1.73
TA
L4-0
3 0.
2818
55
0.00
0017
0.
0035
54
0.12
2706
17
55
0.28
1733
3.
7 1.
19
2.03
2.
19
0.28
1737
2.
5 2.
10
2.29
0.
2817
29
4.7
1.98
2.
10
TAL4
-07
0.28
1772
0.
0000
17
0.00
0966
0.
0267
29
1749
0.
2817
39
3.8
1.19
2.
01
2.18
0.
2817
40
2.4
2.08
2.
29
0.28
1738
4.
9 1.
95
2.09
TA
L4-1
0 0.
2817
29
0.00
0014
0.
0006
82
0.02
0524
17
76
0.28
1705
3.
2 0.
98
2.05
2.
23
0.28
1706
1.
9 2.
12
2.35
0.
2817
05
4.4
1.99
2.
14
TAL4
-12
0.28
1698
0.
0000
11
0.00
0443
0.
0154
92
1671
0.
2816
83
0.0
0.77
2.
08
2.35
0.
2816
84
-1.3
2.
15
2.47
0.
2816
83
1.1
2.02
2.
26
TAL4
-15
0.28
1696
0.
0000
09
0.00
0475
0.
0157
42
1707
0.
2816
80
0.7
0.61
2.
08
2.33
0.
2816
81
-0.6
2.
15
2.45
0.
2816
80
1.8
2.03
2.
24
TAL4
-16
0.28
1709
0.
0000
11
0.00
0714
0.
0208
89
1693
0.
2816
85
0.6
0.77
2.
08
2.33
0.
2816
86
-0.8
2.
15
2.45
0.
2816
85
1.6
2.02
2.
24
TAL4
-18
0.28
1671
0.
0000
11
0.00
0743
0.
0219
85
1725
0.
2816
46
-0.1
0.
77
2.13
2.
40
0.28
1647
-1
.4
2.20
2.
52
0.28
1645
1.
0 2.
07
2.30
TA
L4-2
1 0.
2817
21
0.00
0010
0.
0007
38
0.02
0687
17
32
0.28
1696
1.
9 0.
70
2.06
2.
28
0.28
1697
0.
5 2.
13
2.40
0.
2816
95
3.0
2.01
2.
19
TAL4
-22
0.28
1752
0.
0000
13
0.00
1006
0.
0287
51
1747
0.
2817
18
3.0
0.91
2.
04
2.22
0.
2817
19
1.6
2.11
2.
34
0.28
1717
4.
1 1.
98
2.14
TA
L4-2
4 0.
2817
32
0.00
0016
0.
0011
25
0.03
6718
16
74
0.28
1695
0.
5 1.
12
2.07
2.
32
0.28
1696
-0
.8
2.14
2.
44
0.28
1694
1.
5 2.
01
2.23
TA
L4-2
7 0.
2817
93
0.00
0010
0.
0006
09
0.01
6045
16
77
0.28
1773
3.
3 0.
67
1.96
2.
15
0.28
1774
2.
0 2.
03
2.26
0.
2817
72
4.4
1.91
2.
06
-85-
Chapter 3 Supplementary Material
Blic
hert
-Tof
t et
al,
1997
(1.
93x1
0-11 )
Sch
erer
et
al.,
200
1 (1
.865
x10-1
1 )Biz
zarr
o et
al.,
200
3 (1
.983
x10-1
1 )
Ana
lysi
s 17
6 Hf/17
7 Hf
1 S
.D.
176 Lu
/177 H
f 17
6 Yb/17
7 Hf
AG
EH
f iH
f2S
D
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
H
f iH
f
T DM
(Ga)
T D
MCru
stal
(Ga)
TA
L4-2
8 0.
2817
23
0.00
0008
0.
0004
18
0.01
1802
17
23
0.28
1709
2.
1 0.
55
2.04
2.
26
0.28
1709
0.
8 2.
11
2.38
0.
2817
08
3.2
1.99
2.
17
TAL4
-29
0.28
1719
0.
0000
14
0.00
1345
0.
0353
76
1705
0.
2816
74
0.5
0.98
2.
10
2.35
0.
2816
76
-0.8
2.
17
2.47
0.
2816
73
1.5
2.04
2.
26
TAL4
-30
0.28
1708
0.
0000
08
0.00
0540
0.
0142
60
1720
0.
2816
90
1.4
0.57
2.
07
2.30
0.
2816
90
0.0
2.14
2.
42
0.28
1689
2.
4 2.
01
2.21
TA
L4-3
4 0.
2817
85
0.00
0009
0.
0006
73
0.01
9150
16
78
0.28
1763
3.
0 0.
66
1.97
2.
17
0.28
1764
1.
7 2.
04
2.29
0.
2817
62
4.0
1.92
2.
08
TAL4
-35
0.28
1743
0.
0000
12
0.00
0968
0.
0306
91
1690
0.
2817
11
1.4
0.84
2.
05
2.28
0.
2817
12
0.1
2.12
2.
39
0.28
1710
2.
5 1.
99
2.19
TA
L4-3
6 0.
2813
03
0.00
0019
0.
0009
27
0.02
9083
21
95
0.28
1263
-2
.6
1.33
2.
62
2.91
0.
2812
64
-4.3
2.
72
3.06
0.
2812
62
-1.2
2.
55
2.80
TA
L4-3
7 0.
2817
87
0.00
0017
0.
0005
60
0.01
5839
16
86
0.28
1768
3.
4 1.
19
1.97
2.
15
0.28
1769
2.
0 2.
03
2.27
0.
2817
68
4.4
1.91
2.
07
TAL4
-38
0.28
1711
0.
0000
14
0.00
0744
0.
0219
96
1701
0.
2816
86
0.8
0.98
2.
08
2.32
0.
2816
87
-0.5
2.
15
2.44
0.
2816
85
1.9
2.02
2.
23
TAL4
-39
0.28
1759
0.
0000
14
0.00
1390
0.
0440
41
1704
0.
2817
13
1.8
0.98
2.
05
2.26
0.
2817
14
0.5
2.12
2.
38
0.28
1711
2.
9 1.
99
2.18
TA
L4-4
0B
0.28
1716
0.
0000
14
0.00
1024
0.
0282
35
1730
0.
2816
81
1.3
0.98
2.
08
2.32
0.
2816
82
0.0
2.16
2.
43
0.28
1680
2.
4 2.
03
2.22
TA
L4-4
1 0.
2816
94
0.00
0013
0.
0007
96
0.02
3851
17
07
0.28
1667
0.
3 0.
91
2.10
2.
36
0.28
1668
-1
.1
2.17
2.
48
0.28
1667
1.
3 2.
04
2.27
TA
L4-4
2 0.
2816
99
0.00
0016
0.
0008
88
0.02
4323
17
12
0.28
1669
0.
4 1.
12
2.10
2.
35
0.28
1670
-0
.9
2.17
2.
47
0.28
1668
1.
5 2.
04
2.26
TA
L4-4
3 0.
2817
11
0.00
0020
0.
0007
20
0.01
9292
17
13
0.28
1687
1.
1 1.
40
2.07
2.
31
0.28
1688
-0
.2
2.15
2.
43
0.28
1686
2.
2 2.
02
2.22
TA
L4-4
4 0.
2818
82
0.00
0012
0.
0009
96
0.02
8547
17
27
0.28
1848
7.
1 0.
84
1.86
1.
95
0.28
1849
5.
8 1.
93
2.06
0.
2818
47
8.2
1.81
1.
87
TAL4
-45
0.28
1709
0.
0000
12
0.00
0372
0.
0118
14
1678
0.
2816
97
0.6
0.84
2.
06
2.32
0.
2816
97
-0.7
2.
13
2.44
0.
2816
96
1.7
2.00
2.
23
TAL4
-46
0.28
1731
0.
0000
12
0.00
0542
0.
0153
50
1703
0.
2817
13
1.8
0.84
2.
04
2.26
0.
2817
13
0.4
2.11
2.
38
0.28
1712
2.
9 1.
98
2.17
TA
L4-4
7 0.
2819
74
0.00
0010
0.
0009
41
0.02
9144
16
53
0.28
1943
8.
8 0.
70
1.74
1.
79
0.28
1945
7.
5 1.
80
1.89
0.
2819
43
9.8
1.69
1.
72
TAL4
-49
0.28
1674
0.
0000
11
0.00
1404
0.
0529
05
1731
0.
2816
26
-0.6
0.
77
2.16
2.
44
0.28
1628
-2
.0
2.24
2.
56
0.28
1625
0.
4 2.
10
2.34
TA
L4-5
0 0.
2817
41
0.00
0009
0.
0014
96
0.04
7299
17
15
0.28
1691
1.
3 0.
64
2.08
2.
31
0.28
1692
0.
0 2.
15
2.42
0.
2816
89
2.3
2.02
2.
22
TAL4
-51
0.28
1700
0.
0000
20
0.00
1573
0.
0457
26
1710
0.
2816
47
-0.4
1.
40
2.14
2.
40
0.28
1649
-1
.7
2.21
2.
52
0.28
1646
0.
7 2.
08
2.31
TA
L4-5
2 0.
2816
79
0.00
0007
0.
0007
39
0.02
0934
17
75
0.28
1653
1.
4 0.
51
2.12
2.
35
0.28
1654
0.
0 2.
19
2.47
0.
2816
53
2.5
2.06
2.
25
TAL4
-53
0.28
1831
0.
0000
12
0.00
1102
0.
0317
11
1695
0.
2817
94
4.5
0.84
1.
93
2.09
0.
2817
96
3.2
2.00
2.
20
0.28
1793
5.
5 1.
88
2.01
TA
L4-5
4 0.
2817
07
0.00
0011
0.
0007
08
0.01
9095
16
00
0.28
1685
-1
.6
0.77
2.
08
2.40
0.
2816
86
-2.9
2.
15
2.51
0.
2816
84
-0.6
2.
02
2.30
TA
L4-5
5 0.
2817
80
0.00
0014
0.
0005
95
0.01
5423
17
16
0.28
1760
3.
8 0.
98
1.98
2.
15
0.28
1761
2.
4 2.
05
2.27
0.
2817
59
4.8
1.92
2.
07
Chapter 4
This chapter is published as:
Howard, K.E., Hand, M., Barovich, K.M., Belousova, E.A., 2011. Provenance of late Paleoprotero-zoic cover sequences in the central Gawler Craton: exploring strati graphic correlati ons in east-ern Proterozoic Australia using detrital zircon ages, Hf and Nd isotopic data. Australian Journal
of Earth Sciences, 58, 475-500.
-89-
A Howard, K.E., Hand, M., Barovich, K.M. & Belousova, E.A. (2011). Provenance of late Paleoproterozoic cover sequences in the central Gawler Craton: exploring stratigraphic correlations in eastern Proterozoic Australia using detrital zircon ages, Hf and Nd isotopic data. Australian Journal of Earth Sciences, v. 58 (5), pp. 475-500.
A NOTE:
This publication is included on pages 89-132 in the print copy of the thesis held in the University of Adelaide Library.
A It is also available online to authorised users at:
A http://dx.doi.org/10.1080/08120099.2011.577753
A
Chapter 5
This chapter is published as:
Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Cutt s, K.A., Belousova, E.A., 2011. U-Pb zir-con, zircon Hf and whole-rock Sm-Nd isotopic constraints on the evoluti on of Paleoproterozoic
rocks in the northern Gawler Craton. Australian Journal of Earth Sciences, 58, 615-638.
-137-
A Howard, K.E., Hand, M., Barovich, K.M., Payne, J.L., Cutt s, K.A. & Belousova, E.A. (2011). U-Pb zircon, zircon Hf and whole-rock Sm-Nd isotopic constraints on the evolution of Paleoproterozoic rocks in the northern Gawler Craton. Australian Journal of Earth Sciences, v. 58 (6), pp. 615-638.
A NOTE:
This publication is included on pages 137-168 in the print copy of the thesis held in the University of Adelaide Library.
A It is also available online to authorised users at:
A http://dx.doi.org/10.1080/08120099.2011.594905
A
Chapter 6
-173-
INTRODUCTION
Since the North American conti nent is currently surrounded by thousands of kilome-tres of late Precambrian rift basins, parti cularly on its western margin, geologists have long speculated which conti nental fragments must have previously been positi oned adjacent to it during the Palaeo-Mesoproterozoic. Based on similariti es between event ti melines, recon-structi on models have suggested that Siberia, Balti ca, South China or Australia may have been att ached to North America (Laurenti a; 1 and references therein). However, recent pal-aeomagneti c data now suggest that Siberia and Balti ca were not positi oned adjacent to west-ern Laurenti a, but instead fi t best on its present day northern margins (2). This leaves Australia, Antarcti ca and South China as possibiliti es for the western landmass adjacent to North Amer-ica during the Proterozoic. There are three major confi gurati ons of the Australia-Antarcti ca-Laurenti a recon-structi on. The fi rst is SWEAT, which connects southwestern U.S.A. with east Antarcti ca and Australia positi oned adjacent to Canada. This model is largely based on the similariti es in Neoproterozoic strati graphy, as well as correla-ti ons of Grenvillian aged (1.3-1.1 Ga) orogenic
belts (1 and references therein). Alternati vely, the AUSWUS model places Australia adjacent to the southwestern Laurenti a (1 and refer-ences therein), while AUSMEX places Australia adjacent to Mexico (1 and references therein). The AUSWUS and AUSMEX models are largely based on correlati ons of 1.8-0.8 Ga basement provinces and inferred sedimentary provenance connecti ons between Laurenti a and Australia (1 and references therein). Another reconstruc-ti on, referred to as the “Missing Link” model, places South China between Australia-Antarc-ti ca and Laurenti a (1 and references therein). This reconstructi on is based upon similariti es in the ages of Neoproterozoic strati graphy be-tween Australia, Laurenti a and South China, and att empts to account for variati ons in the age and evoluti on of crustal provinces between Australia, Antarcti ca and Laurenti a. A signifi cant problem with these mod-els is that there is no obvious conti nuati on of the large belt of 1.48-1.35 Ga magmati sm, met-amorphism and deformati on along the south eastern margin of Laurenti a into the proposed conti guous conti nents. Given the scale of this Mesoproterozoic belt across Laurenti a, it seems likely that it would have conti nued into any conti guous domains adjacent to Laurenti a at ca 1.48-1.35 Ga.
Laurenti a and Australia share a widespread 1.45 Ga event within the Rodinian superconti nent
ABSTRACT
The arrangement of conti nental blocks within the Precambrian superconti nent of Rodinia is con-tenti ous. Currently several reconstructi on models juxtapose western Laurenti a with Australia, Antarcti ca, South China, Siberia or Balti ca. New geochronology reveals the existence of ca 1450 Ma magmati sm and metamorphism in Australia. It also builds upon an existi ng widespread data-set of ca 1450 Ma magmati c, Rb-Sr resetti ng, and Ar-Ar cooling ages from regions across eastern Proterozoic Australia. This 1450 Ma widespread tectonothermal event in Proterozoic Australia coincides with the ti ming of voluminous A-type granite emplacement and regional deformati on in southwestern Laurenti a. The intriguing similariti es in the evoluti on of southwestern Laurenti a and Proterozoic Australia lend support to reconstructi on models which place them adjacent dur-ing the Mesoproterozoic.
-174-
Chapter 6 1450 Ma tectonothermal event in Australia
In an att empt to constrain potenti al conti nental confi gurati ons in the Mesoproterozoic, Goodge et al. (3) highlighted the presence of a 1.44 Ga A-type graniti c boulder in a glacial moraine in east Antarcti ca, and the presence of ca 1.4 Ga detrital zircons from the Transantarcti c Moun-tains, suggesti ng these data consti tuted a posi-ti ve test for a SWEAT like confi gurati on at ca 1.45 Ga. Similarly, others (4) have interpreted Cathaysia, (southeastern China), as the conti n-uati on of the Laurenti an Mesoproterozoic belt due to the presence of 1.44-1.43 Ga granitoids and felsic volcanics in southern Cathaysia. In this study we present geochronology from petroleum and mineral explorati on drill holes in the Gawler Craton in southern Aus-tralia that intersect crystalline basement bur-ied beneath thick younger cover sequences. These drill holes provide evidence for ca 1.45 Ga magmati sm and high-grade metamorphism in southern Australia. We have also compiled a dataset of ca 1.5-1.4 Ga magmati sm, shear zone reacti vati on, cooling and isotopic resetti ng from across Proterozoic Australia. This interval also corresponded to rift basin development in northern Australia, and is further represented by the presence of 1.5-1.4 Ga detrital zircons in Mesoproterozoic-Palaeozoic sedimentary suc-cessions in Australia. The combined data point to widespread thermally dominated reworking of predominantly late Palaeoproterozoic (ca 1800-1600 Ma) lithosphere within Australia. We suggest that this record provides a strong case that Australia, rather than Antarcti ca, con-tains the conti nuati on of the Laurenti an 1.48-1.35 Ga granite-rhyolite province. The Austral-ian record therefore provides a broad-based geological framework for the Laurenti an conti -
nental arrangement in the Mesoproterozoic.
THE 1.45 GA RECORD IN AUSTRALIA
Southern Australia is mostly covered by thick Neoproterozoic to recent cover sequences that have only been penetrated by drill holes in a few places to provide samples of the underly-ing basement. LA-ICP-MS monazite dati ng from undeformed granite intersected in the northern Gawler Craton (Figure 1) gives interpreted mag-mati c crystallisati on ages of ca 1460-1440 Ma (Tables 1 & S2-S5). The geochemistry of the ca 1450 Ma granites indicate that they have a per-aluminous character, with steep LREE enriched patt erns and high Ga/Al values suggesti ve of A-type granites (Table S6). Sm-Nd isotopic data (initi al εNd values of -14 to -8.7, and depleted mantle model ages of 3040-2302 Ma) suggest the granites were derived predominantly from melti ng of existi ng crust (Table S7). In additi on, monazite from a migmati ti c bioti te-garnet-pla-gioclase-quartz gneiss from a nearby drill hole gives an age of 1444 ± 10 Ma (Figure 1, Tables 1 & S1). The drill holes that contain the 1.45 Ga magmati c and metamorphic rocks encompass a triangulated region of approximately 1000 km2. Overall in this part of southern Australia, there are less than 60 diamond drill holes in a region of 93,000 km2 that intersect basement. Excluding the 1.45 Ga rocks, the remaining drill holes contain a record of 1.78-1.70 Ga magma-ti sm, sedimentati on and metamorphism (5 and references therein). Given the paucity of drilling and the proporti on of drill holes that contain ca 1.45 Ga rocks it is likely that 1.45 Ga tectonism is more widespread than recorded. Elsewhere in the Gawler Craton there is evidence for tectonism at this ti me. In the
Drillhole Sample Rock Type Age Interpreted age Karkaro1 637614 undeformed Granite 1442 ± 9 Ma timing of crystallisation Karkaro1 637615 undeformed Granite 1463 ± 8 Ma timing of crystallisation
OBD8 163401 undeformed Granite 1458 ± 9 Ma timing of crystallisation 0BD9 163405 orthogneiss 1444 ± 10 Ma timing of metamorphism
Table 1. Summary of geochronology obtained in this study
-175-
Chapter 6 1450 Ma tectonothermal event in Australia
southwestern part of the craton, U-Pb zircon dati ng of pegmati te intersected by mineral ex-plorati on drilling yields an age of 1489 ± 4 Ma (6). On the western edge of the Gawler Craton in the Coompana Block, granites sampled in pe-troleum well Mallabie-1 at a depth of around 1400 metres give ages that range between 1505 ± 7 Ma (7) and 1455 ± 16 Ma (6). 40Ar/39Ar and
monazite data suggest that crustal-scale shear zones in the western Gawler Craton including the Karari, Tallacootra, Coorabie and Kalinjala Shear Zones (Figure 1), were reacti vated or un-derwent cooling at ca 1470-1450 Ma (8-11) at amphibolite to greenschist conditi ons. The pe-riod of structural reacti vati on and cooling also corresponded with widespread resetti ng of Rb-
Figure 1. A) Map showing the ca 1.45 Ga tectonic record in the Gawler Craton and locati ons for drill holes sampled in this study. Pegmati tes in drill hole Nundroo DDH2 intruded at 1.49 Ga (6), and granites in the Mallabie 1 drill hole intruded between 1.5 and 1.45 Ga (6, 7). The Karari, Tallacootra, Coorabie and Kalinjala Shear Zones underwent reacti vati on and/or cooling at ca 1.45 Ma (8-11). Rb-Sr whole isotopic systems in 1.63-1.58 Ga felsic magmati c rocks including the Hiltaba Suite, Gawler Range Volcanics, St Peters Suite and Nuyts Volcanics in the central and southern Gawler Craton underwent regional-scale resetti ng at ca 1.47 Ga (12, 13). B) C) and D) Concordia Plots for monazite grains from granite in drill holes Karkaro1 and OBD8. E) Concordia Plots for monazite grains from a migmati ti c bioti te-garnet-plagioclase-quartz gneiss in drill hole OBD9.
200 km
N
32°00’
30°00’
28°00’
34°00’
135°00’ 138°00’
Karari SZ
Talla
cootra
SZ
Coorabie SZ
132°00’
Karkaro 1
OBD 9OBD 8
Kalinjala SZ
Neoproterozoic-Cambrian Sequences/Cambrian-Ordovician OrogenesisGrenvillean Orogenic Belt with Neoproterozoic-recent cover sequences 1450 Ma Granites Hiltaba Suite (1595-1575 Ma)Gawler Range Volcanics (1595-1590 Ma)St Peter Suite and Nuyts Volcanics (1630-1610 Ma)Paleoproterozoic-Mesoarchean rock systems
1500
1460
1440
14201400
0.23
0.24
0.25
0.26
0.27
2.9 3.0 3.1 3.2 3.3 3.4
E OBD9 1643405 monazite
1560
1500
14201400
2.8 3.0 3.2 3.4 3.6
D OBD8 1643401 monazite
B Karkaro1 637614 monazite1500
14201400
0.22
0.23
0.24
0.25
0.26
0.27
2.8 2.9 3.0 3.1 3.2 3.3
C Karkaro1 637615 monazite
1580
14401400
1360
0.20
0.22
0.24
0.26
0.28
0.30
2.5 2.7 2.9 3.1 3.3 3.5 3.7
Weighted Mean1458 ± 9 Ma
(MSWD=0.33, n=29)
Weighted Mean1444 ± 10 Ma
(MSWD=0.40, n=22)
Weighted Mean1442 ± 9 Ma
(MSWD=0.21, n=20)
Weighted Mean1463 ± 8 Ma
(MSWD=0.60, n=0.93)
206Pb
/238U
207Pb/ 235U
0.23
0.24
0.25
0.26
0.27
0.28
207Pb/ 235U
207Pb/ 235U
207Pb/ 235U
206Pb
/238U
206Pb
/238U
206Pb
/238U
A
1380
1000 km
GC
N
1489 ± 4 Ma
Nundroo DDH2
1505 ± 7 Ma & 1455 ± 16 Ma
granite Mallabie 1
-176-
Chapter 6 1450 Ma tectonothermal event in Australia
Sr whole rock isotope systems in 1.63-1.58 Ga felsic igneous rock suites throughout the cen-tral Gawler Craton (Figure 1). The combined Rb-Sr isotopic whole rock dataset (n = 249) from these felsic suites form an “errorchron” corresponding to 1476 ± 4 Ma (12, 13). The ca 1.45 Ga thermal and structural reworking in the Gawler Craton appears to be part of a widespread system of reworking and resetti ng within Proterozoic Australia (Figure 2). In southwestern Australia, mafi c and inter-mediate magmati c rocks intersected by drilling in basement to the Terti ary Eucla Basin have U-Pb zircon magmati c ages of 1415 ± 7, 1408 ± 7 and 1407 ± 7 Ma respecti vely (14). In the Paterson Orogen, in central Western Australia, monzograniti c and granodioriti c rocks have zir-con U-Pb ages of 1453 ± 10 Ma and 1476 ± 10 Ma (15 and references therein). Further east within the Musgrave Province, monzograniti c magmati sm occurred at 1402 ± 4 Ma (16). In the eastern Mt Isa Province in northeastern Australia, the youngest phases of the Williams Batholith have a U-Pb age of 1493 ± 8 Ma (17). These late phases were approximately coeval with pegmati te intrusions at 1480 ± 14 Ma in the western Mt Isa Province (18). The limited record of ca 1450 Ma magmati sm from the Mt Isa Province appears to be part of a more ex-tensive magmati c system that has not yet been found in outcrop. This assessment is based on the presence of detrital zircons in modern day stream sediment from the eastern Mt Isa Prov-ince that contain a large proporti on (~ 14%) of 1.5-1.4 Ga zircon grains (19). Further evidence for thermal reworking in this part of Proterozo-ic Australia comes from ca 1.5-1.4 Ga 40Ar-39Ar
cooling ages from the Mt Isa and Georgetown Inliers (Tables 2 & S8). Elsewhere in Proterozoic Australia, nu-merous Rb-Sr total rock and mineral isochron ages between 1.5-1.4 Ga have been obtained from magmati c rocks that have U-Pb ages greater than 1.7 Ga (Tables 3 & S9). This sug-gests the existence of widespread, although spati ally dispersed, resetti ng that is dominated by thermal and fl uid-infi ltrati on eff ects as op-posed to tectonism with signifi cant deforma-ti on. The thermal reworking in northeastern Australia recorded by magmati sm, cooling ages and detrital zircons coincided with east-west directed rift basin development at ca 1.49 Ga in the lower Roper Supergroup in northern Aus-tralia (20 and references therein). Elsewhere in Proterozoic Australia, basins may have also formed at approximately this ti me. In the Gawl-er Craton, shales in the Cariewerloo Basin give a Rb-Sr whole rock age of ca 1.4 Ga, which has been interpreted to record the ti ming of di-agenesis (21). In Western Australia, the marine Bangemall Supergroup was deposited in two stages, the Edmund Group between 1.62-1.465 Ga and the Collier Group between ca 1.4-1.07 Ga (22). The Edmund Group is intruded by dol-erite sills at ca 1.465 and 1.07 Ga, suggesti ng it is older than 1.465 Ga, while it overlies the Gas-coyne Complex of which the youngest rocks are around ca 1.62 Ga (22 and references therein). The minimum age of the Collier Group is given by the intrusive 1.07 Ga dolerite sills, while ca 1.4 Ga detrital zircons populati ons within one of the sequences constrain the maximum dep-ositi onal age (22 and references therein).
Table 2. Summary of ca 1450 Ma 40Ar-39Ar cooling ages from Proterozoic Australia
-177-
Chapter 6 1450 Ma tectonothermal event in Australia
Mus
grav
e Pr
ovin
ce
Gaw
ler
Crat
on
Tasm
an Line
Geo
rgin
aBa
sin
Eucl
a Ba
sin
Geo
rget
own
Inlie
rTe
nnan
t Cre
ek
stat
e bo
rder
Sout
h N
icho
lson
Bas
in
Rope
r Su
perg
roup
Cari
ewer
loo
Basi
n
met
amor
phis
m
Maw
son
Crat
on
Bang
emal
l Bas
in
Mt I
sa
050
010
0015
0020
0025
0030
0035
00
n=44
715
.4%
n=3
376.
2%
Nor
ther
n A
mad
eus
Basi
nn=
789
4.7%
n=36
63.
3%
1453
± 1
0 M
a
1442
± 9
Ma
1463
± 8
Ma
1458
± 9
Ma
1415
± 7
Ma
1408
± 7
Ma
1407
± 7
Ma
<149
0 M
a
050
010
0015
0020
0025
0030
0035
00
n=10
445.
8%
n=29
513
.9%
1402
± 4
Ma
1476
± 1
0 M
a
1.5
-1.4
Ga
n=92
80.
8%
1480
± 1
4 M
a14
93 ±
8 M
a
Aru
nta
Prov
ince
Pate
rson
Oro
gen
Am
adeu
s Ba
sin
1471
± 1
4 M
a14
68 ±
12
Ma
1444
± 1
0 M
a
1457
± 2
2 M
a14
89 ±
4 M
a14
55 ±
16
Ma
1505
± 7
Ma
Figu
re 2
. The
dis
trib
uti o
n of
ca
1.45
Ga
even
ts in
Pro
tero
zoic
Aus
tral
ia. I
n ad
diti o
n to
the
Gaw
ler
Crat
on, c
a 1.
45 G
a fe
lsic
mag
mati
sm
is re
cord
ed in
the
Pate
rson
Oro
gen
(15
and
refe
renc
es th
erei
n),
Mus
grav
e Pr
ovin
ce (1
6), M
t Isa
Pro
vinc
e (1
7, 1
8) a
nd b
enea
th th
e Eu
cla
Basi
n (1
4 an
d re
fere
nces
ther
ein)
. Syn
chro
nous
bas
in d
evel
opm
ent o
ccur
red
in th
e M
cArt
hur
Basi
n (2
0), t
he C
arie
wer
loo
Basi
n (2
1) a
nd t
he B
ange
mal
l Sup
erba
sin
(22)
. 40A
r-39
Ar
cool
ing
ages
, Rb-
Sr m
iner
al c
oolin
g ag
es a
nd R
b-Sr
who
le r
ock
resetti
ng a
ges
of c
a 1.
5-1.
4 G
a oc
cur
in r
ocks
from
the
Mt
Isa
Prov
ince
(44
and
refe
r-en
ces
ther
ein,
51
and
refe
renc
es th
erei
n), G
eorg
etow
n In
lier (
45),
Aru
nta
Prov
ince
(46,
47
and
refe
renc
es th
erei
n, 4
8), T
anam
i (49
), an
d Te
nnan
t Cre
ek In
lier (
50).
Prob
abili
ty d
ensi
ty p
lots
sho
w d
etri
tal
zirc
on a
ges
from
Neo
prot
eroz
oic-
mid
Pal
aeoz
oic
(met
a)se
dim
enta
ry r
ocks
from
the
Cen
tral
ian
Supe
rbas
in (3
0 an
d re
fere
nces
the
rein
), an
d M
esop
rote
rozo
ic s
eque
nces
in t
he M
usgr
ave
Prov
ince
(24-
29).
Add
iti on
al a
ge h
isto
gram
s ar
e sh
own
for z
ircon
s sa
mpl
es fr
om m
oder
n da
y dr
aina
ge in
the
Gaw
ler C
rato
n (5
2) a
nd th
e M
t Isa
Pro
vinc
e (1
9). T
he g
rey
bars
spa
n 1.
5-1.
4 G
a. In
Ant
arcti
ca,
a m
orai
ne
host
ed g
raniti c
bou
lder
has
bee
n da
ted
at c
a 1.
44 G
a (3
) and
ca
1.45
Ga
detr
ital g
rain
s oc
cur i
n N
eopr
oter
ozoi
c-Pa
laeo
zoic
sed
imen
tary
uni
ts in
the
Tran
sant
arcti
c M
ount
ains
(3 a
nd re
fere
nces
ther
ein)
.
-178-
Chapter 6 1450 Ma tectonothermal event in Australia
In additi on to the evidence for rock forming and thermal reworking/isotopic reset-ti ng events, sedimentary sequences in central Australia ranging in age between mid-Meso-proterozoic and mid-Paleozoic contain a persis-tent record ca 1.45 Ga detrital zircons (Figure 2). These sequences include Mesoproterozoic units from the southern Arunta region and the Musgrave Province (23-29) as well as Neopro-terozoic to mid-Paleozoic units in the Central-ian Superbasin (30 and references therein). Although the ca 1.45 Ga detrital zircons in the Neoproterozoic to Paleozoic sequences may have undergone multi ple episodes of sedi-mentary recycling, the Mesoproterozoic meta-sedimentary rocks in the Musgrave Province were deposited in the interval 1.45-1.2 Ga (24-29), and are more likely to have been directly sourced from 1450 Ma rocks, with which they are now structurally interleaved (31). Never-theless, the presence of ca 1.45 Ga detrital zir-cons in sedimentary sequences across central Australia, coupled with evidence for rock-form-ing events, thermal reworking and isotopic re-setti ng supports the existence of a widespread ca 1.45 Ga event in Proterozoic Australia.
PROPOSED CONTINENTAL CONFIGURATION AT 1.45 GA
In previous studies, reconstructi on models connecti ng Australia and Laurenti a had been discounted because the 1.48-1.35
Ga Granite-Rhyolite Province appeared to stop abruptly where Australia connected with Lau-renti a (1, 4). However, as we now have a grow-ing dataset supporti ng a widespread ca 1.45 Ga tectonothermal event in Australia, these palaeogeographic reconstructi ons should be reconsidered for this ti me interval. At present, there are no reliable palaeo-magneti c constraints for Australia or Antarcti ca at ca 1.45 Ga. However, reliable palaeomagnet-ic constraints support an Australia-Laurenti a connecti on in a SWEAT-like confi gurati on dur-ing the early Mesoproterozoic at ca 1.595 Ga (32). Similarly, palaeomagneti cally supported reconstructi on models at 1.27 Ga are consist-ent with a SWEAT-like arrangement (2). Given the palaeomagneti c constraints, there is a compelling case for Mesoproterozoic correla-ti ons between Laurenti a and Australia. Previ-ous models (e.g. 3) have essenti ally ignored the record of ca 1.45 Ga tectonism in Proterozoic Australia. Although no in situ 1.45 Ga igneous rocks have been discovered in Antarcti ca, (3) suggested the existence of ca 1.45 Ga granites beneath the ice sheet. This is based on (1) the presence of a moraine-hosted 1.4 Ga gran-ite boulder in the upper Nimrod Glacier area which has A-type geochemical and isotopic characteristi cs and (2) ca 1.45 Ga detrital zir-cons in Neoproterozoic-Paleozoic sedimentary rocks in the Transantarcti c Mountains (3 and references therein). Additi onally there are rare
Table 3. Summary of ca 1450 Ma Rb-Sr and Sm-Nd resetti ng ages from Proterozoic Australia
Region Range of Ages (Ma) Type of Age No. ReferencesArunta 1473 & 1441 Sm Nd isochron (TR & minerals) 2 (46)Arunta 1406 1497 Rb Sr isochron (TR & minerals) 9 (47 and references therein)Arunta 1493 1401 Rb Sr muscovite 8 (48)Arunta 1492 Rb Sr biotite 1 (47 and references therein)Tanami 1473 & 1444 Rb Sr isochron (TR) 2 (49)
Tennant Creek 1473 Rb Sr isochron (TR) 1 (50)Mount Isa 1488 1400 Rb Sr isochron (TR & minerals) 4 (51 and references therein)Mount Isa 1470 1423 Rb Sr biotite & muscovite 5 (51 and references therein)
Georgetown 1488 1440 Rb Sr isochron (TR & minerals) 4 (45)
-179-
Chapter 6 1450 Ma tectonothermal event in Australia
Figure 3. A) Proposed reconstructi on model for Australia-Antarcti ca, Cathaysia and Laurenti a at ca 1.45 Ga. This reconstructi on shows a plau-sible conti nuati on of the Laurenti an 1.48-1.35 Ga Granite-Rhyolite Province into Proterozoic Australia. It also allows a feasible provenance con-necti on between Proterozoic Australia as a source region with the 1.49-1.47 Ga Belt Purcell Basin in Laurenti a and Mesoproterozoic sequences in south Cathaysia that contain detrital zircons with disti ncti vely Australian magmati c ages. The geological depicti on of Laurenti a is aft er (38). B) Reconstructi on model of (3), which places east Antarcti ca adjacent to the 1.48-1.35 Ga Granite-Rhyolite Province in southern Laurenti a, but does not take into considerati on the record of ca 1.45 Ga events in Australia.
Belt Basin
Granite - Rhyolite Province
3
1
2
1
2
3
3
3
3
1
1
1 1
1
2
2
2
2
2
Australia
Cathaysia
1
1(suspected)
1.61-1.49 Ga zircon
4
4
5
5
4
5
A
Australia
Goodge et al. 2008
(suspected)
B
-180-
Chapter 6 1450 Ma tectonothermal event in Australia
ca 1.5-1.4 Ga detrital zircons and monazites in Phanerozoic sediments and sedimentary rocks from central and western Antarcti ca (33, 34) providing some additi onal support for ca 1.45 Ga tectonism in Antarcti ca. Based on this re-cord (3) concluded that east Antarcti ca should be placed adjacent to the Laurenti an 1.55-1.35 Ga Granite-Rhyolite Province, suggesti ng the Antarcti c record provided a positi ve test for conti nental correlati on. In Laurenti a, the 1.48-1.35 Ga Granite-Rhyolite Province is an extensive belt which trends southwest to northeast from north-western Mexico to Ontario (35-37). The prov-ince is characterised by 1.48 to 1.35 Ga A-type granites and related anorthosites which also in-trude Paleoproterozoic crust further west along the belt (35-39). Associated with this event was structural reacti vati on and metamorphism (40, 41), accompanied by ca 1.4 Ga isotopic reset-ti ng and cooling (35). Further north in Lauren-ti a, up to 18 kms of sediment were deposited into the Belt-Purcell Basin during rift ing over the interval 1.47-1.4 Ga (42). Provenance stud-ies from this basin system suggest that material was derived in part from non-Laurenti an sourc-es that supplied 1.61-1.49 Ga zircon grains which correspond to the Laurenti an magmati c gap (43 and references therein). Previous stud-ies have suggested that the most plausible source region for this material was Proterozoic Australia as it contains rocks capable of supply-ing zircon grains in this age range (43 and refer-ences therein). In the context of an Australian connecti on with the Belt Purcell Basin, rift ing in northern Australia associated with the deposi-ti on of the lower Roper Group occurred at the same ti me. The evidence presented above for an extensive ca 1.45 Ga event in Proterozoic Aus-tralia signifi cantly strengthens the geological case that Laurenti a and Australia were conti gu-ous during the early to mid Mesoproterozoic (Figure 3), sharing a common history of Mes-
oproterozoic thermal reworking associated with magmati sm, metamorphism, structural reworking and isotopic resetti ng. Although we cannot defi niti vely preclude the confi gurati on proposed by (3) that places east Antarcti ca ad-jacent to the Laurenti an ca 1.45 Ga belt, the evidence of ca 1450 Ma tectonothermal acti v-ity from Australia is much more extensive than from Antarcti ca. Clearly, ice cover and access limit the availability of informati on from Antarc-ti ca. However the bulk of Proterozoic Australia is also obscured by thick cover. Therefore it is likely that the record of ca 1.45 Ga tectonism in Proterozoic Australian is more extensive than presently recorded, parti cularly from southern Australia where the record is largely restricted to sparse drill hole intersecti ons of basement. In light of the growing body of data which indicates the presence of a 1.45 Ga event in Proterozoic Australia and supports cor-relati on with Laurenti a, strict adherence to the SWEAT model places Australia too far north for a simple conti nuati on of the 1.48-1.35 Ga Gran-ite-Rhyolite Province in Laurenti a. Instead we suggest that a more plausible reconstructi on is to place Australia further south, adjacent to the 1.48-1.35 Ga Laurenti an Granite-Rhyolite Prov-ince (Figure 3). In the reconstructi on shown in Figure 3, we have placed the Gawler Craton ro-tated from its current positi on relati ve to the rest of Proterozoic Australia (32). Additi onally we suggest that Cathaysia was adjacent to west Laurenti a and Australia. This is based on the presence of 1.44-1.43 Ga felsic magmati c rocks on Hainan Island in South Cathaysia (4). Hainan Island also contains late Mesoproterozoic units that have detrital zircons with ages between 1.61-1.49 Ga. No local source rocks have been discovered for these zircons. However one pos-sibility is that the detrital zircons were derived from ca 1.6-1.5 Ga rocks from Proterozoic Aus-tralia, sharing a similar provenance with the older Belt Purcell Group in Laurenti a.
-181-
Chapter 6 1450 Ma tectonothermal event in Australia
CONCLUSIONS
A growing dataset of magmati sm, metamor-phism, cooling, isotopic resetti ng and shear zone reacti vati on at ca 1.45 Ga from regions across Australia suggests that a previously un-recognised widespread tectonothermal event occurred during the Mesoproterozoic. This event can be correlated with the large scale 1.48-1.35 Ga Granite-Rhyolite Province from southern Laurenti a, and suggests that Australia and Laurenti a may have been positi oned adja-cent during the Mesoproterozoic.
ACKNOWLEDGEMENTS
This work was supported by Australian Re-search Council Discovery Project DP1095456, Collins, Hand and Condie, “The enigmati c link between crustal growth and superconti nent formati on”. This contributi on forms TRAX re-cord number XXX.
REFERENCES1. Z. X. Li et al., Precambrian Research 160, 179 (2008).2. D. A. D. Evans, R. N. Mitchell, Geology 39, 443 (2011).3. J. W. Goodge et al., Science 321, 235 (2008).4. Z.-X. Li, X.-H. Li, W.-X. Li, S. Ding, Terra Nova 20, 154 (2008).5. K. E. Howard et al., Australian Journal of Earth Sciences 58, 615
(2011).6. C. M. Fanning, A. J. Reid, G. S. Teale, South Australia. Geological
Survey. Bulleti n 55, (2007).7. B. P. Wade, J. L. Payne, M. Hand, K. M. Barovich, Australian Jour-
nal of Earth Sciences 54, 1089 (2007).8. D. A. Foster, K. Ehlers, Journal of Geophysical Research-Solid
Earth 103, 10177 (1998).9. J. L. Thomas, N. G. Direen, M. Hand, Precambrian Research 166,
263 (2008).10. G. L. Fraser, P. Lyons, Precambrian Research 151, 160 (2006).11. G. M. Swain, M. Hand, J. Teasdale, L. Rutherford, C. Clark, Pre-
cambrian Research 139, 164 (2005).12. A. W. Webb et al., South Australia Department of Primary Indus-
tries and Resources. Report Book 82/86, 136 (1982).13. K. P. Stewart, J. Foden, South Australia Department of Primary
Industries and Resources. Report Book 2003/15, (2003).14. D. R. Nelson, Compilati on of geochronology data, June 2006 up-
date: Western Australian Geological Survey, (2005).15. L. Bagas, Precambrian Research 128, 475 (2004).16. C. L. Kirkland, M. T. D. Wingate, R. H. Smithies, Geochronology
Record 965: Geological Survey of Western Australia, (2011).17. R. W. Page, S. S. Sun, Australian Journal of Earth Sciences 45, 343
(1998).18. K. A. Connors, R. W. Page, Precambrian Research 71, 131 (1995).19. K. C. Condie, M. E. Bickford, R. C. Aster, E. Belousova, D. W. Scholl,
GSA Bulleti n 123, 951 (2011).20. M. J. Jackson, I. P. Sweet, R. W. Page, B. E. Bradshaw, The South Ni-
cholson and Roper Groups: evidence for the early Mesoprotero-zoic Roper Superbasin. B. E. Bradshaw, D. L. Scott , Eds., Integrated Basin Analysis of the Isa Superbasin using Seismic, Well-log and Geopotenti al Data: an Evaluati on fo the Economnic Potenti al of the Northern Lawn Hill Platf orm Australian Geological Survey Or-ganisati on Record 1999/19 (1999).
21. C. M. Fanning, R. B. Flint, W. V. Preiss, South Australia. Geological Survey. Quarterly Geological Notes 88, 11 (1983).
22. D. M. Marti n, A. M. Thorne, Precambrian Research 128, 385 (2004).
23. C. J. Carson et al., Northern Territory Geological Survey, Record 2009-001, (2009).
24. C. L. Kirkland, M. T. D. Wingate, S. Bodorkos, Compilati on of geochronology data: Geological Survey of Western Australia, (2008).
25. C. L. Kirkland, S. Bodorkos, M. T. D. Wingate, H. M. Howard, Ge-ochronology Record 760: Geological Survey of Western Australia, (2009).
26. C. L. Kirkland, M. T. D. Wingate, S. Bodorkos, H. M. Howard, Ge-ochronology Record 758: Geological Survey of Western Australia, (2009).
27. C. L. Kirkland, S. Bodorkos, M. T. D. Wingate, R. H. Smithies, P. M. Evins, Geochronology Record 767: Geological Survey of Western Australia, (2009).
28. C. L. Kirkland, S. Bodorkos, M. T. D. Wingate, R. H. Smithies, Ge-ochronology Record 797: Geological Survey of Western Australia, (2009).
29. B. P. Wade, D. E. Kelsey, M. Hand, K. M. Barovich, Precambrian Research 166, 370 (2008).
30. D. W. Maidment, I. S. Williams, M. Hand, Basin Research 19, 335 (2007).
31. B. P. Wade, PhD, University of Adelaide (2006).32. J. L. Payne, M. Hand, K. M. Barovich, A. Reid, D. A. D. Evans, in
Geological Society Special Publicati on. (2009), pp. 319-355.33. J. J. Veevers, A. Saeed, N. Pearson, E. Belousova, P. D. Kinny, Gond-
wana Research 14, 343 (2008).34. J. J. Veevers, A. Saeed, P. E. O’Brien, Sediment. Geol. 211, 12
(2008).35. J. L. Anderson, R. L. Cullers, Rocky Mountain Geology 34, 149
(1999).36. J. W. Goodge, J. D. Vervoort, Earth and Planetary Science Lett ers
243, 711 (2006).37. J. L. Anderson, E. E. Bender, Lithos 23, 19 (1989).38. S. J. Whitmeyer, K. E. Karlstrom, Geosphere 3, 220 (2007).39. J. V. Jones, S. A. Rogers, J. N. Connelly, Rocky Mountain Geology
45, 1 (2010).40. J. V. Jones, C. S. Siddoway, J. N. Connelly, Lithosphere 2, 119
(2010).41. M. W. Nyman, K. E. Karlstrom, E. Kirby, C. M. Graubard, Geology
22, 901 (1994).42. K. V. Evans, J. N. Aleinikoff , J. D. Obradovich, C. M. Fanning, Cana-
dian Journal of Earth Sciences 37, 1287 (2000).43. G. M. Ross, M. Villeneuve, Bulleti n of the Geological Society of
America 115, 1191 (2003).44. R. A. Spikings, D. A. Foster, B. P. Kohn, G. S. Lister, Tectonophysics
349, 327 (2002).45. L. P. Black, T. H. Bell, M. J. Rubenach, I. W. Withnall, Tectonophys-
ics 54, 103 (1979).46. J. Foden, J. Mawby, S. Kelley, S. Turner, D. Bruce, Precambrian Re-
search 71, 207 (1995).47. R. D. Shaw, L. P. Black, Australian Journal of Earth Sciences 38, 307
(1991).48. W. J. Collins, I. S. Williams, S. E. Shaw, N. A. McLaughlin, Precam-
brian Research 71, 91 (1995).49. R. W. Page, D. H. Blake, M. W. Mahon, BMR Journal of Australian
Geology & Geophysics 1, 1 (1976).
-182-
Chapter 6 1450 Ma tectonothermal event in Australia
50. L. P. Black, BMR Journal of Australian Geology & Geophysics 2, 111 (1977).
51. R. W. Page, T. H. Bell, Journal of Geology 94, 365 (1986).52. E. A. Belousova, A. J. Reid, W. L. Griffi n, S. Y. O’Reilly, Lithos 113,
570 (2009).53. J. L. Payne, M. Hand, K. M. Barovich, B. P. Wade, Australian Jour-
nal of Earth Sciences 55, 623 (2008).54. J. N. Aleinikoff et al., Geological Society of America Bulleti n 118,
39 (2006).55. D. Maidment, Australian Nati onal University (2005).56. S. E. Jackson, N. J. Pearson, W. L. Griffi n, E. A. Belousova, Chemical
Geology 211, 47 (2004).57. A. Michard, P. Gurriet, M. Soudant, F. Albarede, Geochimica Et
Cosmochimica Acta 49, 601 (1985).
-183-
Chapter 6 Supplementary Material
Methods
Basement rocks in the northern Gawler Craton are not exposed, so samples in this
study were taken from diamond drill holes that were completed as a part of regional
mineral exploration programs.
Analytical techniques for in situ U Pb monazite dating follow the method of Payne et
al. (53). Prior to analysis monazite grains were imaged prior to analysis via a back scattered
electron on a Phillips XL20 SEM at the University of Adelaide. U Pb isotopic analyses were
obtained using a New Wave 213nm Nd YAG laser in a He ablation atmosphere, coupled to
an Agilent 7500cs/7500s ICP MS at the University of Adelaide. U Pb fractionation was
corrected using the MAdel monazite standard (53) and the 44069 monazite standard (53,
54). Accuracy was checked with an in house monazite standard 94 222/Bruna NW (53, 55).
The 207Pb/206Pb monazite ages were used. Data were processed using the program “Glitter”
developed at Macquarie University, Sydney (56).
Whole rock geochemical analyses were undertaken at Amdel Limited, South
Australia.
-184-
Chapter 6 Supplementary Material
Table S1.
Drill core intervals and locations, and analytical methods undertaken on samples from thenorthern Gawler Craton, Australia.
Drillhole DetailsLocation
(GDA94, Z 53)Sample Sample Depth (m) Analyses
InterpretedLithology
Name No. Eastings Northings From To geochem mz Nd
Karkaro 1 3552 380270 6835938 637614 477.39 477.57 Granite
637615 479.70 480.01 Granite
OBD 8 1577 286298 6788087 660840 175.00 175.10 Orthogneiss
660841 175.10 175.20 Orthogneiss
1643400 175.25 175.84 Orthogneiss
1643401 180.00 180.40 Granite
OBD 9 1592 293375 6809107 1643403 389.30 389.80 Orthogneiss
660842 391.95 392.25 Orthogneiss
1643405 396.10 396.50 Orthogneiss
-185-
Chapter 6 Supplementary Material
Table S2.
U Pb monazite analyses for sample 1643405 from drill hole OBD9
Radiogenic Ratios Age (Ma)
207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s 207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s % Con
M14 0.09201 0.0011 0.24518 0.0035 3.11645 0.0469 1468 22 1414 18 1437 12 96
M16 0.09195 0.0011 0.25101 0.0036 3.18852 0.0493 1466 23 1444 19 1454 12 98
M15 0.09162 0.0011 0.24901 0.0036 3.15178 0.0472 1459 22 1433 18 1445 12 98
M18 0.09156 0.0010 0.25628 0.0037 3.24192 0.0474 1458 21 1471 19 1467 11 101
M17 0.09150 0.0012 0.25054 0.0036 3.16696 0.0497 1457 24 1441 19 1449 12 99
M10 0.09146 0.0011 0.24744 0.0035 3.12588 0.0466 1456 22 1425 18 1439 11 98
M6 0.09141 0.0011 0.25631 0.0036 3.23503 0.0475 1455 22 1471 19 1466 11 101
M3 0.09124 0.0011 0.25255 0.0035 3.18125 0.0458 1451 22 1452 18 1453 11 100
M4 0.09102 0.0010 0.25168 0.0035 3.16259 0.0450 1447 21 1447 18 1448 11 100
M9 0.09097 0.0011 0.25268 0.0036 3.17515 0.0485 1446 23 1452 19 1451 12 100
M20 0.09080 0.0011 0.25274 0.0036 3.16851 0.0480 1442 24 1453 19 1450 12 101
M11 0.09078 0.0011 0.25493 0.0037 3.19658 0.0479 1442 22 1464 19 1456 12 102
M13 0.09074 0.0012 0.24528 0.0035 3.07458 0.0489 1441 25 1414 18 1426 12 98
M12 0.09056 0.0011 0.24942 0.0035 3.12033 0.0460 1437 22 1436 18 1438 11 100
M22 0.09044 0.0013 0.25542 0.0037 3.18845 0.0518 1435 27 1466 19 1454 13 102
M28 0.09044 0.0012 0.25100 0.0037 3.13555 0.0496 1435 24 1444 19 1442 12 101
M23 0.09024 0.0011 0.24665 0.0035 3.07348 0.0454 1431 23 1421 18 1426 11 99
M25 0.09019 0.0011 0.25094 0.0036 3.12646 0.0477 1429 23 1443 19 1439 12 101
M8 0.09013 0.0010 0.25370 0.0036 3.15735 0.0457 1428 21 1458 18 1447 11 102
M7 0.09011 0.0011 0.25302 0.0035 3.14845 0.0470 1428 23 1454 18 1445 11 102
M19 0.08975 0.0012 0.25313 0.0037 3.13814 0.0495 1420 24 1455 19 1442 12 102
M2 0.08966 0.0011 0.25498 0.0035 3.15706 0.0458 1418 22 1464 18 1447 11 103
-186-
Chapter 6 Supplementary Material
Table S3.
U Pb monazite analyses for sample 1643401 from drill hole OBD8.
Radiogenic Ratios Age (Ma) 207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s 207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s % Con
M08 0.09324 0.0016 0.26601 0.0038 3.42576 0.0631 1493 32 1521 20 1510 14 102
M11 0.09277 0.0013 0.25684 0.0035 3.29091 0.0524 1483 27 1474 18 1479 12 99
M07 0.09268 0.0013 0.26502 0.0037 3.39324 0.0536 1481 26 1515 19 1503 12 102
M22 0.09236 0.0014 0.25313 0.0036 3.22917 0.0548 1475 29 1455 18 1464 13 99
M05 0.09228 0.0010 0.26538 0.0035 3.38310 0.0468 1473 21 1517 18 1501 11 103
M26 0.09205 0.0012 0.25346 0.0034 3.22235 0.0473 1468 24 1456 17 1463 11 99
M16 0.09204 0.0012 0.25667 0.0035 3.26322 0.0485 1468 24 1473 18 1472 12 100
M04 0.09199 0.0011 0.26690 0.0036 3.39192 0.0496 1467 23 1525 18 1503 11 104
M21 0.09198 0.0013 0.25550 0.0035 3.24594 0.0513 1467 26 1467 18 1468 12 100
M28 0.09191 0.0012 0.26723 0.0037 3.39221 0.0529 1465 26 1527 19 1503 12 104
M10 0.09190 0.0011 0.24259 0.0032 3.07985 0.0443 1465 24 1400 17 1428 11 96
M03 0.09176 0.0014 0.24858 0.0035 3.15056 0.0532 1462 29 1431 18 1445 13 98
M30 0.09173 0.0012 0.25394 0.0034 3.21835 0.0472 1462 24 1459 17 1462 11 100
M02 0.09164 0.0013 0.26189 0.0036 3.31515 0.0539 1460 28 1500 18 1485 13 103
M14 0.09164 0.0012 0.25167 0.0034 3.18568 0.0487 1460 25 1447 17 1454 12 99
M01 0.09151 0.0012 0.25853 0.0034 3.26793 0.0476 1457 24 1482 18 1474 11 102
M23 0.09150 0.0012 0.25005 0.0034 3.16056 0.0476 1457 25 1439 17 1448 12 99
M20 0.09150 0.0012 0.25291 0.0034 3.19696 0.0480 1457 24 1454 18 1456 12 100
M06 0.09134 0.0015 0.25889 0.0037 3.26603 0.0569 1454 30 1484 19 1473 14 102
M24 0.09131 0.0010 0.25611 0.0034 3.23027 0.0439 1453 21 1470 17 1465 11 101
M19 0.09125 0.0012 0.25557 0.0035 3.22135 0.0490 1452 25 1467 18 1462 12 101
M09 0.09124 0.0010 0.25297 0.0033 3.18811 0.0431 1452 21 1454 17 1454 10 100
M18 0.09102 0.0012 0.25105 0.0034 3.15673 0.0469 1447 24 1444 17 1447 11 100
M17 0.09079 0.0012 0.25189 0.0034 3.15948 0.0467 1442 24 1448 17 1447 11 100
M25 0.09066 0.0011 0.25325 0.0034 3.17113 0.0441 1439 22 1455 17 1450 11 101
M27 0.09066 0.0013 0.25428 0.0035 3.18401 0.0507 1439 27 1461 18 1453 12 101
M29 0.09062 0.0012 0.25295 0.0035 3.16612 0.0485 1439 25 1454 18 1449 12 101
M12 0.09050 0.0011 0.25901 0.0035 3.23811 0.0473 1436 24 1485 18 1466 11 103
M15 0.09030 0.0012 0.25066 0.0034 3.12649 0.0477 1432 25 1442 18 1439 12 101
-187-
Chapter 6 Supplementary Material
Table S4.
U Pb monazite analyses for sample 637614 from drill hole Karkaro 1. Data in grey italics areconsidered outliers and are not included in the age calculations or shown on the concordiaor weighted average plots.
Radiogenic Ratios Age (Ma)
207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s 207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s % Con
M12 0.09231 0.0010 0.25971 0.0037 3.30484 0.0476 1474 20 1488 19 1482 11 101
M11 0.09131 0.0010 0.25139 0.0036 3.16458 0.0463 1453 21 1446 19 1449 11 99
M03 0.09124 0.0010 0.23682 0.0035 2.97902 0.0435 1452 21 1370 18 1402 11 94
M19 0.09122 0.0010 0.25351 0.0037 3.18852 0.0459 1451 20 1457 19 1454 11 100
M16 0.09111 0.0010 0.25558 0.0037 3.21074 0.0460 1449 20 1467 19 1460 11 101
M02 0.09105 0.0009 0.25407 0.0037 3.18928 0.0456 1448 19 1459 19 1455 11 101
M04 0.09101 0.0010 0.25548 0.0037 3.20556 0.0462 1447 20 1467 19 1459 11 101
M08 0.09099 0.0010 0.24508 0.0036 3.07417 0.0451 1446 20 1413 18 1426 11 98
M13 0.09075 0.0010 0.25497 0.0037 3.19024 0.0462 1441 20 1464 19 1455 11 102
M14 0.09073 0.0010 0.24526 0.0035 3.06787 0.0441 1441 20 1414 18 1425 11 98
M15 0.09072 0.0010 0.25583 0.0037 3.19939 0.0463 1441 20 1469 19 1457 11 102
M06 0.09066 0.0009 0.25475 0.0037 3.18444 0.0460 1439 19 1463 19 1453 11 102
M10 0.09065 0.0010 0.25378 0.0037 3.17221 0.0462 1439 20 1458 19 1450 11 101
M20 0.09065 0.0010 0.25576 0.0037 3.19619 0.0470 1439 21 1468 19 1456 11 102
M07 0.09064 0.0010 0.25140 0.0037 3.14151 0.0467 1439 21 1446 19 1443 11 100
M05 0.09064 0.0010 0.25264 0.0037 3.15725 0.0459 1439 20 1452 19 1447 11 101
M18 0.09057 0.0010 0.25450 0.0037 3.17776 0.0464 1437 21 1462 19 1452 11 102
M17 0.09047 0.0011 0.25773 0.0038 3.21425 0.0487 1435 22 1478 19 1461 12 103
M01 0.09041 0.0010 0.25261 0.0037 3.14836 0.0460 1434 20 1452 19 1445 11 101
M09 0.09027 0.0010 0.25563 0.0038 3.18233 0.0481 1431 22 1468 19 1453 12 103
-188-
Chapter 6 Supplementary Material
Table S5.
U Pb monazite analyses for sample 637615 from drill hole Karkaro 1. Data in grey italics areconsidered outliers and are not included in the age calculations or shown on the concordiaor weighted average plots.
Radiogenic Ratios Age (Ma)
207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s 207Pb/206Pb 1s 206Pb/238U 1s 207Pb/235U 1s % Con
M05 0.09796 0.0010 0.14500 0.0021 1.95854 0.0281 1586 19 873 12 1101 10 55
M07 0.09503 0.0010 0.26016 0.0038 3.40832 0.0484 1529 19 1491 19 1506 11 98
M29 0.09426 0.0010 0.27922 0.0040 3.62804 0.0518 1513 20 1587 20 1556 11 105
M28 0.09300 0.0010 0.25910 0.0037 3.32166 0.0472 1488 20 1485 19 1486 11 100
M08 0.09283 0.0009 0.25217 0.0037 3.22731 0.0460 1484 19 1450 19 1464 11 98
M13 0.09266 0.0009 0.24367 0.0034 3.11281 0.0424 1481 19 1406 18 1436 10 95
M16 0.09251 0.0009 0.25675 0.0036 3.27355 0.0447 1478 19 1473 18 1475 11 100
M25 0.09246 0.0009 0.26643 0.0038 3.39556 0.0475 1477 19 1523 19 1503 11 103
M21 0.09238 0.0009 0.25632 0.0037 3.26421 0.0457 1475 19 1471 19 1473 11 100
M03 0.09226 0.0010 0.26801 0.0039 3.40761 0.0492 1473 20 1531 20 1506 11 104
M01 0.09223 0.0010 0.24573 0.0036 3.12320 0.0454 1472 20 1416 19 1438 11 96
M04 0.09223 0.0009 0.26857 0.0039 3.41455 0.0484 1472 19 1534 20 1508 11 104
M09 0.09220 0.0009 0.27132 0.0039 3.44881 0.0489 1471 19 1548 20 1516 11 105
M06 0.09205 0.0009 0.27874 0.0040 3.53696 0.0502 1468 19 1585 20 1536 11 108
M18 0.09193 0.0009 0.25228 0.0035 3.19692 0.0436 1466 19 1450 18 1456 11 99
M02 0.09190 0.0009 0.27039 0.0039 3.42624 0.0481 1465 19 1543 20 1510 11 105
M10 0.09189 0.0009 0.28458 0.0041 3.60523 0.0511 1465 19 1614 21 1551 11 110
M14 0.09185 0.0009 0.25035 0.0035 3.16910 0.0436 1464 19 1440 18 1450 11 98
M15 0.09139 0.0009 0.23388 0.0033 2.94639 0.0403 1455 19 1355 17 1394 10 93
M19 0.09128 0.0009 0.22559 0.0032 2.83812 0.0393 1452 19 1311 17 1366 10 90
M12 0.09121 0.0009 0.25795 0.0036 3.24296 0.0446 1451 19 1479 19 1468 11 102
M26 0.09099 0.0009 0.26628 0.0038 3.33978 0.0473 1446 19 1522 20 1490 11 105
M23 0.09098 0.0010 0.26055 0.0037 3.26761 0.0464 1446 20 1493 19 1473 11 103
M24 0.09084 0.0009 0.25971 0.0037 3.25207 0.0455 1443 19 1488 19 1470 11 103
M30 0.09080 0.0009 0.25891 0.0037 3.24022 0.0454 1442 19 1484 19 1467 11 103
M27 0.09070 0.0009 0.26523 0.0038 3.31606 0.0469 1440 19 1517 19 1485 11 105
M20 0.09065 0.0009 0.25663 0.0036 3.20741 0.0436 1439 19 1473 18 1459 11 102
M22 0.08944 0.0009 0.26188 0.0038 3.22840 0.0452 1414 19 1500 19 1464 11 106
-189-
Chapter 6 Supplementary Material
Tabl
eS6
.
Maj
oran
dtr
ace
elem
enta
naly
sis
for
drill
core
sam
ples
from
the
nort
hern
Gaw
lerC
rato
n,A
ustr
alia
.n.
a.=
nota
naly
sed
b.d
=be
low
dete
ctio
nlim
it.
Sam
ple
Maj
ors
(Wt%
)RE
E(p
pm)
SiO
2Ti
O2
Al 2O
3Fe
2O3
MnO
MgO
CaO
Na 2
OK 2
OP 2
O5
LOI
LaCe
PrN
dSm
EuG
dTb
Dy
Ho
ErTm
YbLu
OBD
816
4340
059
0.9
177.
50.
123.
84.
62.
12.
80.
22.
065
110
1450
91.
66
1.0
5.5
0.9
2.6
0.4
2.2
0.3
OBD
816
4340
172
0.3
131.
90.
020.
80.
32.
67.
00.
11.
016
030
033
105
152.
49
1.3
6.0
0.9
2.5
0.3
1.9
0.3
OBD
916
4340
359
0.8
177.
40.
183.
10.
61.
37.
60.
12.
175
145
1760
112.
27
1.2
6.5
1.1
3.2
0.5
3.2
0.5
Kark
aro
6376
1472
0.2
142.
30.
020.
50.
43.
16.
30.
1n.
a.10
518
520
6413
1.4
91.
47.
51.
43.
50.
52.
70.
4
Kark
aro
6376
1572
0.2
141.
70.
020.
40.
52.
96.
70.
1n.
a.96
175
1960
111.
28
1.2
6.0
1.0
2.4
0.3
1.4
0.2
Det
ectio
nlim
it0.
010.
005
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.5
0.5
0.05
0.02
0.02
0.02
0.05
0.02
0.02
0.02
0.05
0.05
0.05
0.02
Sam
ple
Trac
e(p
pm)
Ag
As
BaBe
BiCd
CoCr
CsCu
Ga
Hf
InM
oN
bN
iPb
RbSb
ScSe
SnSr
TaTe
ThTl
UV
WY
ZnZr
OBD
816
4340
00.
2b.
d.43
5n.
a.b.
d.b.
d.65
705.
52.
027
n.a.
b.d.
0.9
1824
1622
0b.
d.15
b.d.
n.a.
255
n.a.
b.d.
201.
42
115
n.a.
2710
017
5
OBD
816
4340
10.
31.
558
0n.
a.0.
1b.
d.70
b.d.
1.8
5.0
17n.
a.b.
d.1.
118
b.d.
4727
0b.
d.b.
d.b.
d.n.
a.17
5n.
a.0.
214
51.
74
b.d.
n.a.
3227
260
OBD
916
4340
30.
30.
589
0n.
a.0.
10.
195
8548
.03.
026
n.a.
b.d.
2.2
2243
4335
0b.
d.15
0.5
n.a.
90n.
a.b.
d.37
2.1
310
0n.
a.32
115
145
Kark
aro
6376
14b.
d.0.
580
03.
0b.
d.0.
432
b.d.
1.5
1.5
257
b.d.
1.2
20b.
d.46
310
b.d.
b.d.
1.0
b.d.
76b.
d.b.
d.60
1.8
7b.
d.28
032
2920
0
Kark
aro
6376
15b.
d.2.
043
04.
5b.
d.0.
223
b.d.
2.2
2.5
266
b.d.
0.8
20b.
d.52
320
b.d.
b.d.
1.0
b.d.
62b.
d.b.
d.94
2.0
9b.
d.18
525
3017
0
Det
ectio
nlim
it0.
10.
520
0.5
0.1
0.1
0.2
200.
10.
50.
11
0.5
0.1
0.5
20.
50.
10.
55
0.5
100.
12
0.2
0.1
0.1
0.1
200.
10.
050.
520
-190-
Chapter 6 Supplementary Material
Table S7.
Sm Nd isotope data. (a) 143Nd/144Nd CHUR(0) = 0.512638, 147Sm/144Nd CHUR(0) = 0.1966. (b)TDM calculated using the single stage model of Michard et al. (57).
Drill hole Sample Rock typeSm
(ppm)Nd
(ppm)147Sm/144Nd 143Nd/144Nd 2 SE Nd(0)a eNd(T) TDM
b Age
OBD 08 660840 Orthogneiss 6.7 37.9 0.1079 0.511381 9 -24.5 -4.6 2305 1750 OBD 08 660841 Orthogneiss 12.0 89.5 0.0810 0.511179 8 -28.5 -2.5 2083 1750 OBD 08 1643400 Orthogneiss 7.4 40.5 0.1111 0.511431 12 -23.6 -4.4 2522 1750 OBD 08 1643401 Granite 11.2 81.0 0.0834 0.511162 9 -28.8 -7.8 2302 1450 OBD 09 660842 Orthogneiss 7.5 41.1 0.1147 0.511476 6 -22.6 -4.3 2316 1750 OBD 09 1643403 Orthogneiss 9.0 51.9 0.1052 0.511336 12 -25.4 -4.9 2309 1750
Karkaro 1 367614 Granite 13.0 68.7 0.1143 0.511138 10 -29.3 -14.0 2779 1450 Karkaro 1 367615 Granite 9.1 52.0 0.1056 0.511325 10 -25.6 -8.7 2332 1450
-191-
Chapter 6 Supplementary Material
-192-
Chapter 6 Supplementary Material
Table S8.
Ca 1450 Ma 40Ar 30Ar cooling ages from Proterozoic Australia.
Rock RegionCooling Age
(Ma)Type of Age Ref.
Biotite Schist, Tommy Creek Block Mount Isa 1481 ± 5 40Ar/30Ar biotite (44 and references therein)
Dolerite, Tommy Creek Block Mount Isa 1457 ± 5 40Ar/30Ar hornblende (44 and references therein)
Limestone, Mitakoodi Culmination Mount Isa 1400 ± 5 40Ar/30Ar white mica (44 and references therein)
Volcaniclastic, Boomarra Horst Mount Isa 1458 ± 6 40Ar/30Ar hornblende (44 and references therein)
Granite, Boomarra Horst Mount Isa 1408 ± 5 40Ar/30Ar biotite (44 and references therein)
Granite, Naraku Batholith Mount Isa 1454 ± 4 40Ar/30Ar biotite (44 and references therein)
Granite, Naraku Batholith Mount Isa 1493 ±8 40Ar/30Ar hornblende (44 and references therein)
Granite, Naraku Batholith Mount Isa 1435 ± 5 40Ar/30Ar biotite (44 and references therein)
Microgranite, Naraku Batholith Mount Isa 1436 ± 8 40Ar/30Ar biotite (44 and references therein)
Granite, Williams Batholith Mount Isa 1456 ± 2 40Ar/30Ar hornblende (44 and references therein)
Granite, Williams Batholith Mount Isa 1442 ± 7 40Ar/30Ar biotite (44 and references therein)
Granite, Williams Batholith Mount Isa 1446 ± 3 40Ar/30Ar biotite (44 and references therein)
Granite, Williams Batholith Mount Isa 1428 ± 8 40Ar/30Ar biotite (44 and references therein)
Biotite Schist, Williams Batholith Mount Isa 1405 ± 5 40Ar/30Ar biotite (44 and references therein)
Biotite Schist, Williams Batholith Mount Isa 1400 ± 5 40Ar/30Ar white mica (44 and references therein)
Granite, Williams Batholith Mount Isa 1435 ± 3 40Ar/30Ar biotite (44 and references therein)
Granite, Williams Batholith Mount Isa 1455 ± 2 40Ar/30Ar hornblende (44 and references therein)
Granite, Osborne, Cloncurry area Mount Isa ca 1465 40Ar/30Ar muscovite (44 and references therein)
Granite, Osborne, Cloncurry area Mount Isa ca 1465 40Ar/30Ar sericite (44 and references therein)
Ernest Henry Cu Au deposit, Cloncurry area Mount Isa ca 1478 40Ar/30Ar biotite (44 and references therein)
Mt Elliot, Cloncurry area Mount Isa ca 1496 40Ar/30Ar biotite (44 and references therein)
Wimberu Mount Isa ca 1476 40Ar/30Ar sericite (44 and references therein)
Albite pipe/ Gilded Rose Breccia Mount Isa ca 1488 40Ar/30Ar sericite (44 and references therein)
Granite, Wonga Granite Mount Isa 1425 ± 7 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1447 ± 8 40Ar/30Ar biotite (44)
Rhyodacite, Leichhardt volcanics Mount Isa 1426 ± 6 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1488 ± 2 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1483 ± 14 40Ar/30Ar hornblende (44)
Granite, Kalkadoon Granite Mount Isa 1444 ± 4 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1489 ± 12 40Ar/30Ar hornblende (44)
Granite, Kalkadoon Granite Mount Isa 1453 ± 7 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1470 ± 9 40Ar/30Ar biotite (44)
Granite, Kalkadoon Granite Mount Isa 1432 ± 3 40Ar/30Ar biotite (44)
Granite, One tree Granite Mount Isa 1419 ± 7 40Ar/30Ar hornblende (44)
Granite, Yeldham Granite Mount Isa 1496 ± 10 40Ar/30Ar biotite (44)
Amphibolite, Eastern creek volcanics Mount Isa 1430 ± 2 40Ar/30Ar hornblende (44)
Amphibolite, Eastern creek volcanics Mount Isa 1439 ± 5 40Ar/30Ar hornblende (44)
Granite, Sybella Granite Mount Isa 1444 ± 9 40Ar/30Ar biotite (44)
Einasleigh Metamorphics Georgetown ca 1444 40Ar/30Ar hornblende (45)
Robertson River Metamorphics Georgetown ca 1456 40Ar/30Ar muscovite (45)
Robertson River Metamorphics Georgetown ca 1478 40Ar/30Ar muscovite (45)
Table S9.
Ca 1450 Ma Rb Sr resetting ages from Proterozoic Australia. *Rb Sr isochron ages have beenrecalculated with 87Rb decay constant of 1.42 x 1011y. TR = Total Rock.
Rock RegionResetting Age
(Ma)Type of Age Ref.
Gabbro, Huckitta Bore Intrusion Arunta 1473 ± 134 Sm Nd isochron (minerals) (46)
Mafic amphibolites, Entia Gneiss Complex Arunta 1441 ± 152 Sm Nd isochron (TR & minerals) (46)
Pegmatites & metasomatic pods, Anmatjira Reynolds Range Arunta 1493 1401 Rb Sr muscovite (8 ages) (48)
Felsic rocks, Woolanga Bore, Strangways Ranges Arunta 1406 ± 80* Rb Sr isochron (TR) (47 and references therein)
Ultramafic rocks, Johannsen’s Mine, Strangways Ranges Arunta 1426 ± 37* Rb Sr isochron (TR) (47 and references therein)
Jinka Granite, Jervois Range area Arunta 1479 ± 23 Rb Sr isochron (TR & minerals) (47 and references therein)
Alaskitic granite/Unca Granite, Jervois Range area Arunta 1459 ± 10 Rb Sr isochron (TR & minerals) (47 and references therein)
Mica Schist/Bonya Schist, Jervois Range area Arunta 1492 Rb Sr biotite (47 and references therein)
Microgranodiorite xenolith in Harverson Granite Arunta 1497 ± 146 Rb Sr isochron (TR) (47 and references therein)
Wangala Granite Arunta 1490 ± 100 Rb Sr isochron (TR) (47 and references therein)
Wuluma Granitoid Arunta 1426 ± 81 Rb Sr isochron (TR) (47 and references therein)
Deformed Granite, Anmatjira Range Arunta 1424 ± 58 Rb Sr isochron (TR) (47 and references therein)
Mylonitic Gneiss, Redbank Thrust Zone Arunta 1480 ± 160 Rb Sr isochron (TR) (47)
Pollock Hill Formation Tanami 1444 ± 220* Rb Sr isochron (TR) (49)
Mount Webb Granite Tanami 1473 ± 21* Rb Sr isochron (TR) (49)
Cabbage Gum Granite Tennant Creek 1473 ± 54* Rb Sr isochron (TR) (50)
Kalkadoon Granite Mount Isa 1470 1423 Rb Sr biotite & muscovite (5 ages) (51 and references therein)
Argylla Formation, Argylla Range and Duck Creek Area Mount Isa 1400 ± 64 Rb Sr isochron (TR & minerals) (51 and references therein)
Argylla Formation, Mt Olive area Mount Isa 1488 ± 101 Rb Sr isochron (TR) (51 and references therein)
Sybella Microgranite Mount Isa 1427 ± 465 Rb Sr isochron (TR) (51)
Tuff samples from the Urquhart Shale, Mount Isa Group Mount Isa 1482 ± 52 Rb Sr isochron (TR) (51 and references therein)
Einasleigh Metamorphics, Stockmans Crossing Georgetown 1440 ± 70 Rb Sr isochron (TR) (45)
Robertson River Metamorphics, Stars Well Georgetown 1488 ± 35 Rb Sr isochron (TR) (45)
Robertson River Metamorphics, Bull Creek Georgetown 1468 ± 31 Rb Sr isochron (TR & minerals) (45)
Digger Creek Granite, Percyville Georgetown 1460 ± 40 Rb Sr isochron (TR) (45)
Chapter 7
-195-
Conclusions
The fi rst major aim of this project was to investi gate the provenance of (meta)sedimentary sequences of the Gawler Craton, and integrate the informati on with existi ng data in order to bett er understand the potenti al paleogeographic setti ng of the Gawler Craton. A second goal was to constrain the ti melines of metamorphism and magmati sm in the western and northern Gawler Craton, and to match these events with other crustal blocks both within and external to Proterozoic Australia. Both of these aims helps to constrain paleogeographic reconstructi on models which seek to explain the development of Proterozoic Australia within a wider context.
Chapter 2 demonstrates that provenance studies using detrital zircon data should be complemented with Hf and Nd isotopic data, otherwise coincidental similariti es in zircon age populati ons could lead to matches with incorrect and disprovable source regions. The case study shows that Paleoproterozoic metasedimentary rocks in the eastern Gawler Craton have the detrital zircon age populati ons that would be expected from erosion of the proximal pre-existi ng Gawler Craton. A provenance study based on detrital zircon patt ern matching alone would conclude that the Gawler Craton was the source region to these metasedimentary rocks. However, whole rock Nd isotopic data show that the average Gawler Craton is too isotopically evolved to be considered a major source to the more juvenile metasedimentary sequences. Furthermore, Hf isotopic data indicate that ca 2000 Ma zircons from the Gawler Craton are signifi cantly more evolved than the ca 2000 Ma detrital zircons from the metasedimentary rocks. The combinati on of bulk rock Nd and Hf zircon data suggest that the Gawler Craton is not a viable source region for the metasedimentary packages, despite the striking similarity between detrital zircon ages and zircon crystallisati on events within
the craton. As well as the case study which highlights the signifi cance of Hf and Nd isotopic data in provenance studies, several more regional conclusions were obtained in Chapter 2. The depositi onal interval of the Corny Point Paragneiss, in the south eastern Gawler Craton, is constrained to the interval ca 1870 – 1850 Ma using detrital zircon ages coupled with post-depositi onal tectonism. The source region to these metasedimentary sequences must be capable of supplying slightly evolved (Nd (1850
Ma) = –1 to –5) sediments and detrital zircons with ages of 2000 Ma, 2450 Ma and 2510 Ma. In additi on, the source region must be able to supply isotopically juvenile (Hf = +2 to +5) ca 2000 Ma detrital zircon grains. The source region to these metasedimentary rocks is unknown at this ti me, but the ca 2000 Ma juvenile zircons are similar in age and compositi on to zircon grains derived from tuff aceous rocks in the Pine Creek Orogen in northern Australia.
Chapter 3 presents a provenance study on metasedimentary rocks from drill core in the Fowler Domain, western Gawler Craton. The maximum depositi onal ages from detrital zircon analyses are between ca 1760 – 1710 Ma. Minimum depositi onal ages of ca 1690 – 1670 Ma are given by metamorphic zircon and monazite ages. The sedimentary precursors were derived from an evolved and enriched intracrustal source region dominated by 1790 – 1710 Ma zircon forming events, suggesti ng derivati on from the Arunta Province of the North Australian Craton. The depositi onal ti ming and provenance characteristi cs of the Fowler Domain metasedimentary rocks are similar to other Paleoproterozoic basins from the Gawler Craton and the Curnamona Province, including the Mt Woods Domain, the northern Gawler Craton, the Wallaroo Group and the lower Willyama Supergroup. This suggests that widespread Paleoproterozoic depositi on throughout the South Australian Craton was predominantly sourced from
-196-
Chapter 7 Conclusions
the Arunta region of the North Australian Craton. If the Arunta region was the source to the Paleoproterozoic basin systems of the Gawler Craton and Curnamona Province, then a connecti on between the South Australian Craton and the North Australian Craton must have existed by at least 1760 to 1710 Ma.
Chapter 4 presents a provenance study on three (meta)sedimentary sequences from the central Gawler Craton. Previously the Eba, Labyrinth and Tarcoola Formati ons had all been thought to be Paleoproterozoic in age. However, the results show that each of three formati ons is not only diff erent in age but also were sourced from diff erent crustal domains. Provenance data from the Eba Formati on show that it is derived from a highly evolved source with a detrital zircon spectrum consisti ng only of Archean grains which give a maximum depositi onal age of ca 2540 Ma. The Eba Formati on may be either (1) Paleoproterozoic in age with derivati on solely from Archean Gawler Craton sources in isolati on from <2500 Ma source regions or (2) as preferred, Archean in age and a possible equivalent to metasedimentary rocks of the Sleaford and Mulgathing Complexes. Further constraints are needed to identi fy the ti ming of depositi on for the Eba Formati on. The ca 1715 Ma Labyrinth Formati on appears to be a correlati ve with other late Paleoproterozoic basins from the Gawler Craton. These were highlighted in Chapter 3 and include metasedimentary rocks of the northern Gawler Craton, Fowler Domain, Mt Woods Domain and Wallaroo Group. However, slightly more evolved isotopic Nd signatures and a greater proporti on of Archean detrital zircons suggest that the Labyrinth Formati on in comparison with other Paleoproterozoic sequences, was dominated by reworked Archean material. This Archean source material is consistent with derivati on from the Meso- to Neoarchean Gawler Craton, and is also consistent with derivati on from the unconformably underlying
Eba Formati on. Provenance data from the 1650 Ma Tarcoola Formati on show that it requires a felsic, isotopically juvenile source region and cannot be accounted for by derivati on of the average Archean Gawler Craton. Proterozoic rocks such as the proximal Tunkillia Suite of the central Gawler Craton, or the Warumpi Province of the North Australian Craton are possible source regions. The age and isotopic compositi on of the Tarcoola Formati on is similar to sequences in the Curnamona Province and also in northeastern Australia, suggesti ng the existence of a widespread basin system that received fi ll from a comparati vely juvenile felsic terrain.
Chapter 5 presents geochronology, geochemistry and isotopic Nd analyses on orthogneisses obtained from drill core in the northern Gawler Craton. U-Pb zircon dati ng on the orthogneisses suggests that they were emplaced at around 1780 – 1750 Ma. However, insuffi cient inherited grains were found to determine the age of the crust that they intruded. U-Pb dati ng on metamorphic zircon and monazite suggests that the orthogneisses underwent metamorphism between 1730 – 1710 Ma, consistent with the craton wide Kimban Orogeny. The northern Gawler Craton can now be shown to share similar ti melines of magmati sm, sedimentary depositi on and metamorphism with the Arunta Province of the North Australian Craton, suggesti ng that they may been conti guous and shared similar tectonic histories during the mid to late Paleoproterozoic. Another outcome of this study is that the orthogneisses of the northern Gawler Craton, in additi on to the previously proposed Arunta region, can now be considered as a possible source region for Paleoproterozoic basin sequences of the Gawler Craton and Curnamona Province menti oned in Chapters 3 and 4, which require an enriched felsic source region that can supply 1780 – 1750 Ma zircon grains.
-197-
Chapter 7 Conclusions
Chapter 6 presents new ca 1450 Ma magmati sm and high-grade metamorphism from the northern Gawler Craton. This matches with a growing dataset of 1.45 Ga magmati sm, metamorphism, cooling, isotopic resetti ng and shear zone reacti vati on within Proterozoic Australia, suggesti ng the existence of a widespread 1.45 Ga tectonothermal event. Its plausible that this event could be an extension of the 1.48 – 1.35 Ga Granite – Rhyolite Province from southern Laurenti a, supporti ng reconstructi on models which place Proterozoic Australia and Laurenti a adjacent during the Mesoproterozoic.
Implicati ons for reconstructi on models including Proterozoic Australia
There are several implicati ons for Proterozoic reconstructi on models that can be made from the data presented in this thesis.
1. The provenance data from Paleoproterozoic rocks in the Gawler Craton suggest that the Gawler Craton was more or less assembled prior to ca 1.7 Ga.
2. The similariti es in magmati sm, metamorphism and sedimentary depositi on between the northern Gawler Craton and the Arunta Province, as well as provenance characteristi cs from 1.7 Ga sedimentary sequences of the Gawler Craton, suggest that the North Australian Craton and South Australian Craton were likely to be conti guous at ca 1.7 Ga.
3. The presence of a 1.45 Ga tectonothermal event in Proterozoic Australia suggests that Proterozoic Australia may have been positi oned adjacent to Laurenti a at 1.45 Ga.