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MINERALS PROSPECTIVITY ASSESSMENT:

PROPOSED RESERVE AREAS

FOR

INDEPENDENT VERIFICATION GROUP

Ross Large and Andrew McNeil

24 February, 2012

24/02/2012

MINERALS PROSPECTIVITY ASSESSMENT FOR

INDEPENDENT VERIFICATION GROUP

Ross R Large and Andrew W. McNeill

1.0 EXECUTIVE SUMMARY

2.0 INTRODUCTION

2.1 PURPOSE

2.2 RELEVANT TERMS OF REFERENCE

2.3 BACKGROUND ON TASMANIAN GEOLOGY AND ORE DEPOSITS

3.0 METHODOLOGY FOR THE MINERAL PROSPECTIVITY ASSESSMENT

3.1 INTRODUCTION

3.2 MINERAL DEPOSIT MODELS

3.3 TRACT MAPS

3.4 INTERPRETATION

3.5 OUTPUTS

4.0 RESULTS OF THE ASSESSMENT

4.1 TASMANIA-WIDE RESULTS

4.2 RESULT FOR THE NOMINATED 572,000 HECTARES

4.3 RESERVE CLASSIFICATIONS & IMPACT OF MINING IN RESERVES

APPENDICES

APPENDIX 1, EXAMPLE MINERAL DEPOSIT MODEL

APPENDIX 2, DEPOSIT TYPE WEIGHTINGS

APPENDIX 3, MINERAL POTENTIAL MAPS

APPENDIX 4, SUMMARY OF RESERVE AREAS ASSESSED TO HAVE VERY HIGH POSPECTIVITY

APPENDIX 5, STRUCTURE OF “IGA AREAS GEOLOGY COMMENTS CODES

COMPLETED_V4.XLS”

1. EXECUTIVE SUMMARY

The mineral potential of the 572,000 hectare reserve areas nominated by the

Tasmanian Forests Intergovernmental Agreement was assessed in the context

of the overall mineral potential of the State, taking into account all available

geoscientific and mineral deposit data.

This assessment indicates that 45% of the nominated reserve area has low to

moderate mineral potential, 22% has high mineral potential and 33% has very

high mineral potential.

It is recommended that the 55% of high to very high mineral potential reserves

be given a land tenure classification that enables mineral exploration and

mining in the future.

The current mining operations and leases in Tasmania cover 0.8% of the total

land surface of the state. It is anticipated that new discoveries in the high

potential reserve areas are unlikely to add more than another 0.1% of surface

area, making a total of less than 1.0% of Tasmania used for mining purposes.

2. INTRODUCTION

2.1 PURPOSE

This report is an assessment of the mineral resource potential of Tasmania with a

particular focus on the 572,000 hectare reserve areas nominated in the Tasmanian

Forests Intergovernmental Agreement. The purpose is to inform the Independent

Verification Group (IVG) on land tenure classifications that respect areas of high

mineral potential within the nominated reserves.

2.2 RELEVANCE TO IVG TERMS OF REFERENCE

This report is relevant to the following terms of reference:

5. Assess and provide advice about stakeholder claims relating to conservation

values, areas and boundaries of potential reserves from within the ENGO-nominated

572,000 hectares of High Conservation Values native forest. (Clauses 20 and 28).

9f. Provide advice on known potential economic development opportunities and the

conservation values in the areas identified in 5 above to inform government decisions

on appropriate land tenure (clause 29).

2.3 BACKGROUND ON TASMANIAN GEOLOGY AND ORE DEPOSITS

Tasmania has a diverse and complex geology (Fig. 1) with a series of mineralisation

events that have contributed to the formation of a range of ore deposit types that are

mainly concentrated in the west, north-west and north-east of the state (Fig.2).

There are currently sixteen operating mines and six mineral processing plants in the

state, with a further nine mining projects under development. Mineral exports account

for over 51% of total Tasmania exports by value.

The principle Tasmania mineral ore types and related rock types, in order of

geological history are:

Magnetite (Fe3O4) lenses (called skarn) hosted in mafic volcanics and

sedimentary carbonates of the Arthur Metamorphic Complex in western

Tasmania; formed 500-550 million years ago.

Magnesite (MgCO3) lenses hosted in the Arthur Metamorphic Complex in

western Tasmania; formed 500-550 million years ago.

Volcanic Hosted Massive Sulfide deposits (VHMS) containing zinc, lead,

copper, silver and gold, hosted in the Mount Read Volcanics of western

Tasmania; formed 490 to 510 million years ago. Several of these deposits

FIGURE 1. SIMPLIFIED GEOLOGY OF TASMANIA (SOURCE: MRT).

FIGURE 2. LOCATION OF MAJOR MINES, PROSPECTS, PROJECTS, AND INFRASTRUCTURE.

(SOURCE: MRT WEBSITE).

contain very high grades of metal and are considered to be “world class” deposits

(Large et. al, 1992; 2001)

Gold in quartz veins in western Tasmania and north eastern Tasmania, hosted

by a variety of sedimentary rock types and related to Devonian deformation

and granite intrusion; formed 400 to 410 million years ago. Referred to as

slate-belt gold.

Tin and tungsten skarn, replacement and vein deposits occurring within and

around major granite intrusions located in western and north eastern

Tasmania, including the “World Class” hard-rock Sn resource at Renison;

formed 320 to 400 million years ago

Zinc, lead and silver veins within the outer halo of the same granite intrusions,

but further from the granite; also formed 320 to 400 million years ago.

Disseminated nickel sulfide lenses within early Cambrian ultramafic rocks of

western Tasmania, which have been concentrated by Devonian granite

intrusions; formed 320 to 360 million years ago.

High purity silica flour (SiO2) developed by the break down of silicified

Neoproterozoic dolomites found in western, north western and south western

Tasmania. The concentration and purification of the silica flour took place in

the Tertiary, between 2 and 65 million years ago.

Minerals earnings from Tasmania mines, amounted to $557 million in 2010, from the

following metal concentrates, in order of value;

copper-zinc; from VHMS deposits

iron; from magnetite skarn deposits

gold; from VHMS and slate belt gold deposits

tin; from replacement tin deposits

lead-zinc-silver; from VHMS and vein deposits

others, including silica.

Mineral commodities consumed locally in Tasmania include limestone, dolomite, coal,

construction materials and dimension stone.

The above list of ore deposit types that are common to Tasmania are a subset of a

much larger global list (e.g. Cox and Singer, 1986). Because certain ore types are

known to occur in particular geological settings, then we have considered 45 ore

types (termed mineral or ore deposit models) from the global list, that have potential

to occur in the state, based on the known geology of Tasmania. Twelve of the 45 ore

types are most relevant to Tasmania and have had the most influence on our

prospectivity assessment. The twelve high priority ore types, including a Tasmania

example and their approximate in-ground value are listed in Table 1.

TABLE 1: MAJOR ORE DEPOSIT TYPES THAT ARE MOST RELEVANT TO THIS

ASSESSMENT

ORE DEPOSIT TYPE TASMANIAN EXAMPLE PRE-MINING IN-GROUND

VALUE*

Magnetite skarn Savage River 37 billion

VHMS - polymetallic Rosebery 32.4 billion

VHMS copper-gold Mt Lyell 15.7 billion

Tin replacement Renison 7.5 billion

Tin-tungsten skarn Mt Lindsay 4.7 billion

Avebury Ni Avebury 4.2 billion

Sediment-hosted gold Beaconsfield 3.4 billion

VHMS - gold Henty 1.9 billion

Sn-W-Mo veins Foley Zone (Cleveland) 0.8 billion

Silica flour Corinna 0.53 billion

Magnesite Arthur River 39.7 billion

Lateritic Ni Barnes Hill 1.2 billion

*AU$, exchange rates and metal prices as at October 2011;

italics indicates has not been mined

3. METHODOLOGY FOR THE MINERAL PROSPECTIVITY ASSESSMENT

3.1 Introduction

Mineral prospectivity assessments can be either quantitative or qualitative; however,

both methods rely on the development of:

a. Mineral Deposit Models (or Ore Deposit Models) as discussed above,

summarise the geological environment (including age range, host rocks,

tectonic setting etc), characteristics (physical and chemical), lists criteria

on which the potential for each ore deposit type can be assessed, and

may include an indication of economic significance of the deposit type.

b. Mineral Deposit Tract Maps which are derived from geological maps and

define the area in which a mineral deposit model indicates a particular

deposit type may occur. These tracts are subdivided into areas of differing

potential for the deposit type, based on the degree of fit with the criteria

summarised in the mineral deposit model.

In the quantitative methodology, the mineral deposit models and tract maps are the

first component of a three part assessment, the other components being:

2. Development of a grade-tonnage model which is used to estimate the likely

characteristics of un-discovered ore bodies.

3. Estimating the number of un-discovered ore bodies using the grade-

tonnage model and a Monte Carlo simulation.

This methodology has been promoted by the USGS (e.g., Singer and Berger, 2007;

Singer, 2007) and has been applied to orogenic Au deposits in Victoria (Lisitsin et al.,

2007, 2009) and, in a modified form, for VHMS deposits in Tasmania (unpublished

Pasminco Exploration Reports, 2000).

However, in this assessment we have used a qualitative methodology as:

a. There are not sufficient numbers of deposits in Tasmania, to produce grade-

tonnage models for most deposit types and global grade-tonnage models

(such as those summarised in Cox and Singer, 1986) are either not available,

e.g. Avebury Ni type, or are not applicable, e.g., Tasmanian Polymetallic

VHMS deposits have higher grades and tonnages than global examples.

b. The qualitative method is also well established and was used for 12 Regional

Forest Agreements (RFAs) in 4 states of Australia (for example see Anon,

1998b).

3.2 Mineral Deposit Models

The current analysis for the IVG relies on the Mineral deposit models provided to the

1996 RFA process, in which a total of 45 mineral deposit models were cited (see

Anon, 1996). In the RFA process the mineral deposit models for metallic deposits

were largely derived from Cox and Singer (1986), and models for non-metallic and

construction materials were compiled from a range of sources. At a meeting on 17

October 2011, between Geoscience Australia (GA) and Mineral Resources Tasmania

(MRT) geologists and the authors, the existing mineral deposit models were reviewed

and updated, with the following changes made:

The SEDEX and Sed-hosted Cu models were removed (replaced by the

‘metalliferous euxinic shale’ and Cobar models respectively).

Cu-skarn, Volcanic-hosted magnetite, and precious- and semi-precious stone

models removed.

The Tin vein and Tungsten – Molybdenum vein models were combined (into

Sn-W-Mo vein model)

Geothermal Energy, Rare Earth Element (REE), and Noril’sk Ni, models were

added.

Avebury Ni model (a deposit type unknown in 1996) added.

Lateritic Ni model (Barnes Hill near Beaconsfield– not previously considered

to be a viable target) added.

Construction materials originally grouped under one model were split into

unconsolidated (clay, gravel and sand), and hard rock models.

This process resulted in a total of 45 mineral deposit models for consideration (Table

2). All models have been further reviewed in the light of developments in mineral

deposit models (e.g., upgraded models as published in Anon (1998a), or USGS

Mineral Deposit models website [http://minerals.cr.usgs.gov/team/depmod.html]) and

improvements in regional geological understanding, particularly related to the 3D

distribution of major rock units (largely from the WTRMP 3D model which improved

interpretation of geology at depth, i.e., depth to basement under Mesozoic and

younger cover – particularly in southeast Tasmania). Documentation and full

descriptions of the 45 Mineral Deposit Models will be provided by MRT in a separate

report, but an example is included as Appendix 1.

3.3 Tract maps

Mineral tracts prepared for this assessment were based on:

1:500,000 and 1:250,000 scale digital geological maps of Tasmania.

TABLE 2: MINERAL DEPOSIT MODELS CONSIDERED IN THIS ASSESSMENT

No. Model Tract map name model_code1 Ag bearing polymetallic veins agveins2 agvein_12 Au assoc with Alkaline Intrusives alkpor2 alkpor3 Placer Au alluv_au alluv_au4 Au-BM-Sn veins ausnven2 ausven25 Avebury-style Ni avebNi avebNi6 Bauxite bauxite bauxite7 Besshi type Massive Sulphide besshi4 besshi8 Metalliferous black shales blk_shales blk_sha9 Sediment hosted Au (Carlin Type) carlin carlin10 Placer Cr chrompla chrompla11 Basaltic Cu cubaslt3 cubaslt12 Epithermal Au-Ag epiau3 epiau13 Synorogenic nickel-copper deposits gabbro2 gabbro214 Geothermal Energy geothermal geoth15 W-Sn-Cu-magnetite skarns gr_all2 WSnskarn16 Sn greisen greisen greisen17 Au in Ironstones istone2 istone18 Irish-style base metal istyle istyle19 Lateritic Ni laterNi laterNi20 Au assoc with VHMS mrv3 VHMS_Au21 Polymetallic style VHMS mrv4 Kuroko22 Ni associated with Jurassic dolerite norilsk norilsk23 Alluvial Sn placersn placersn24 Mt Lyell type Cu-Au porphcu porphCu25 REE Heavy Mineral Sands ree_hms ree_hms26 Proterozoic magnetite skarn savage2 savage27 Slate Belt Au sbelt3 sbelt28 Replacement Sn sn_repl sn_repl29 Sn-W-Mo veins snven3_2 SnWMo_v30 Early Cambrian Ultramafic-related Ni umafic3 umafic31 Sandstone-hosted U uranium2 uranium32 Coal coal2 coal33 Dolomite dolomite dolomite34 Limestone lime lime35 Magnesite mgsite mgsite36 Ochre ochre ochre37 Oil Shale oilsh oilshale38 Shoreline placer Ti shore2_p placerTi39 Silica Flour silfr silflr40 Zeolites zeolite zeolite41 Silica Hard rock silica silica42 Dimension stone dimension43 Construction - hard rock conmat_hr44 Construction - sand, gravel, clay conmat_cgs45 Cobar Style Cu+/-Au, Zn, Pb cobar sed_Cu

Compilations of geophysical data (particularly magnetics, gravity and seismic)

which have been used to support geological interpretations used in 1, above,

and 3, below.

The 2002 WTRMP geological model of Tasmania (Murphy et al., 2002), a

state wide 3D geological model (extending from surface to approximately

10km depth) coupled with an updated sub-surface granite model (not yet

publicly available – see Leaman and Richardson (2003) for most recent

available version).

The distribution of known mineral occurrences, prospects and deposits (MRT

Mirloch database).

Geological reports and compilations (e.g., publicly available results from

mineral exploration and internal MRT publications such as Bacon et al.

(2008)).

The Mineral Deposit Models.

Mineral Potential tract maps showing areas considered to have potential for 42 of the

45 mineral deposit types were produced (see Figure A1 in Appendix 3 for an

example) and the individual ‘tracts’ on these maps were rated for their potential, from

High (18) to Low (1). These ratings rely in particular, on the presence of the requisite

geological setting as defined in the deposit model, but also reflect the level of

geological understanding of an area and/or whether the target outcropping at surface

or obscured/covered by younger geological units.

For example, on Figure A1 of Appendix 2, areas, either outcropping or under shallow

(<500m, but generally <200m) younger cover, of the Mount Read Volcanics, which

host polymetallic (Kuroko)-style VHMS are rated as High Potential. In contrast, areas

where the Mount Read Volcanics are interpreted to occur under thick (>500m) cover,

they are assigned Low-Moderate Potential because, 1. The depth of burial reduces

the probability of a mineral discovery and 2. The available geoscientific data, do not,

with a high degree of certainty, indicate the presence of buried Mount Read

Volcanics.

Definitions of the relative levels of potential are included in Chapter 5, Appendix A of

the RFA documentation (Anon, 1996), and are summarised in Table 3.

TABLE 3: CLASSIFICATION OF POTENTIAL USED FOR INDIVIDUAL TRACTS IN THE CURRENT

ASSESSMENT.

3.4 Interpretation

For this report we have considered the mineral potential of the whole state, and from

that assessment, focused on the potential of the proposed individual reserve areas.

The process involved a number of steps:

1. Generation of tract maps and assignment of mineral potentials (as discussed

above).

2. Assigning a deposit ‘weighting factor’ to each deposit type, based on its

relevance to Tasmania, size/grade and findability. These assignments, and the logic

behind them are discussed in Appendix 3.

3. Combination of individual tract maps to produce ‘composite’, ‘cumulative,’

‘weighted composite’ and ‘weighted cumulative’ mineral potential maps for the entire

state (see appendix 4 for discussion).

4. Assignment of maximum composite, cumulative, weighted composite, and

weighted cumulative values (from the combined tract maps) to each of the 270

proposed reserve areas.

5. Assignment of an “assessed mineral potential” value (low-moderate, high, very

high) to each reserve area based on the maximum composite and cumulative values

for mineral deposit tracts within each reserve area. The assessed mineral potential

was assigned using the following criteria:

0

high high

N/A

very high

Total score

Max s

co

re

12

0 21 65

highlow/moderate

6. The ‘assessed mineral potential’ was then re-evaluated, for each proposed

reserve area, and where necessary re-defined on the basis of:

Underlying geology (from 1:250,000 digital geology maps); some areally

restricted, but potentially high prospectivity, rock types, such as the

Ordovician limestones near Zeehan, are not included on the current tract

maps.

The presence of mineral deposits and resources (from the Mirloch database

and the locations of Mining Leases and Retention Licences) in each of the

proposed reserve areas. For example some coal resources currently held

under retention licences were not apparent on the current tract maps.

Proximity to mineralised trends or areas, that may not be currently held

under Mining Lease or Retention Licenses. For example, the Mathinna Au

trend.

Economic factors that are not covered in the initial assessment, in particular,

there is no formal weighting for “strategically’ important deposit types which

include:

Those considered critical for Australian economic prosperity and security (e.g., Rare Earth Elements, Platinum Group Elements, Vanadium, Potash, Lithium and Chromium).

Commodities which may face restricted supply, for example, China currently controls >75% of global Sn, and W resources

Commodities that are important for the Tasmanian economy – particularly construction materials and those used in agriculture, e.g., limestone and dolomite (for example, 99% of the area of outcropping dolomite in southern Tasmania is unavailable for exploration /exploitation due to various reserves).

In this process it was recognised that as currently defined some larger proposed

reserve areas may include tracts with variable assessed mineral potential. It may

therefore be desirable to subdivide these areas on the basis of the assessed mineral

potential of individual mineral tracts within that area, rather than applying a single

score to the entire area (see Figure 3).

3.5 Outputs

Deliverables are:

tract maps, both digital and hard copies and as a combined tract shape file.

a report providing details of each mineral deposit model (to be compiled by

MRT)

mineral potential map of the whole state, and a map of the specified reserve

areas

a spreadsheet with comments and ranking for each proposed reserve area (or

sub-area if proposed reserves overlie areas of varying mineral prospectivity).

See Appendix 5 for a description.

other supporting data as requested by the Reference Group, including in-situ

values (in AU$ per tonne of ore) that were requested at the meeting on

22/11/11 (see Appendix 2).

4. SUMMARY OF RESULTS

4.1 State-Wide mineral potential

The weighted cumulative mineral potential map (Figure A4 in Appendix 3) derived

from this assessment outlines the highest mineral potential as:

1. Areas where there is overlap of the Cambrian Mt Read Volcanics and the

Devonian granite halos, due to the multiple weightings associated with several

deposit types hosted in either the volcanics or the granite halos.

2. The Mount Read volcanics for Cu, Zn, Pb, Ag and Au

3. The Devonian Granite halos for Sn, W, Pb, Ag and Au

4. The Arthur Metamorphic Complex for Fe, Mg, Au and Si

5. Proterozoic carbonates for Si flour

6. Cambrian to Silurian turbidite sequences for slate belt Au

4.2 Mineral Potential of proposed reserve areas

Twenty seven of the proposed reserves overlap with outcrop areas of the Mount

Read Volcanics, a further 48 overlap with halo zones of the Devonian granites, and 6

cover parts of the Arthur Mobile Belt. All these reserves (or parts of them) have very

high mineral potential. Many of these areas cover current mining leases. In total 55%

of the area proposed for reservation is assessed as having high to very high mineral

potential, and 45% is assessed to have low to moderate mineral potential (Fig. 3).

The reserves with very high mineral potential are listed, with a brief summary of the

reasons for the assessment of each, in Appendix 4.

4.3 Reserve Classifications and Impacts of Mining in Reserve Areas

In Tasmania, the Reserves currently nominated as Conservation Areas, Regional

Reserves and Nature Recreation Areas, allow exploration and mining under strict

guidelines. We recommend that the 55% of proposed new reserves that have high to

very high mineral potential, be given a similar reserve classification, that allows

mineral exploration and mining under strict guidelines.

Given the size of the high potential proposed reserves (3,025 km2), compared to the

size of the state (68,400 km2), and taking into account the area occupied by the

current mining operations, and associated tenements, in the state (543.25 km2), it

may be deduced that any future mines in the proposed reserves will likely occupy less

than 24 km2, or 0.43% of the area of the proposed reserves.

The footprint and environmental impact of any new mining operation in the reserve

areas will depend on the type of ore deposit found, the mineralogy, climate,

processing methods and the mining method (e.g. Seal and Foley, 2002). This cannot

be predicted with any certainty due to the large range of variables, and will require

assessment on a case-by-case basis, after a discovery has been made. In

environmentally sensitive areas, there is a general move toward underground mining

with a minimum surface footprint. This is exemplified by the Henty Gold Mine in

western Tasmania, which has won several national awards for environmental best

practice. However not all mines can be underground, for example silica flour at

Corinna, in western Tasmania, is mined from shallow open cuts that occupy an area

of about 4 hectares, and are progressively rehabilitated, under strict guidelines

developed by the state Department of the Environment. The possibility of more

intrusive types of mining (e.g. large-scale open cut mining) cannot be predicted based

on our assessment and current data. This can only be done on a case by case basis

after a discovery is made, and factors such as depth of deposit below surface, grade

of deposit, strength and structure of rocks, sulfide content of ores, composition of

wall-rocks, amongst others, are known with certainty.

FIGURE 3. SUMMARY OF ASSESSED MINERAL POTENTIAL FOR THE 270 PROPOSED

RESERVE AREAS (note: areas of differing potential are approximate only and reference

to the digital map is necessary for accurate boundary locations).

ACKNOWLEDGEMENTS

Compiling this report would have been difficult without the timely assistance of

personnel at MRT, in particular we would like to acknowledge Geoff Green and Mike

Vicary for compiling the Mineral Deposit Models and David Green and Jo-Anne

Bowerman for assistance with GIS issues. Geoff Green and Subhash Jarieth, from

Geoscience Australia, also provided advice based on their experience of pervious

prospectivity analyses. Others who contributed to the ore deposit models were Clive

Calver, Ralph Botrill and Jafar Taheri of MRT and Alison Kirkby, Tony Meixner, Ed

Gerner, Dean Hoatson and Subhash Jaireth of GA.

REFERENCES

Anonymous, 1996. Tasmanian-Commonwealth Regional Forest Agreement, Social

and economic report Vol. VI, Supplementary appendices to Volume 3, Background

Report Part D. Public Land Use Commission, 272p.

Anonymous, 1998a. Exploration models for major Australian Mineral deposit types,

AGSO Journal of Australian Geology and Geophysics, V17 number 4, 313p.

Anonymous, 1998b. Assessment of Mineral and Hydrocarbon Resources in the

South-West Forest Region of Western Australia. Joint Commonwealth and Western

Australian Regional Forest Agreement (RFA) Steering Committee report, 145p.

Bacon, C.A., Calver, C.R., and Pemberton, J., 2008. The industrial mineral deposits

of Tasmania. Geological Survey Mineral Resources Report 13, 48p.

Cox, D.P., and Singer, D.A., 1986. Mineral Deposit Models, USGS Bulletin 1693,

379p.

Green, G.R., and Jareith, S., 1996. Panel of Experts evaluation of RFA Social &

economic minerals projects, 12p.

Large, R.R., 1992. Australian Volcanic-Hosted Massive Sulfide Deposits - Features, Styles, And Genetic Models, Economic Geology 87:471-510. Large, R.R., McPhie, J., Gemmell, J.B., Herrmann, W., and Davidson, G.J., 2001. The Spectrum of Ore Deposit Types, Volcanic Environments, Alteration Halos, and Related Exploration Vectors in Submarine Volcanic Successions: Some Examples from Australia Economic Geology 96:913-938. Lisitsin, V.A., Olshina, A, Moore, D.H., Willman, C.E., 2007. Assessment of

undiscovered mesozonal gold endowment under cover in the northern part of the

Bendigo Zone (Victoria). Gold undercover report 2, Victorian Department of Primary

Industries, 98p.

Lisitsin, V.A., Olshina, A, Moore, D.H., Willman, C.E., 2009. Assessment of

undiscovered mesozonal gold endowment under cover in the northern part of the

Stawell Zone (Victoria). Gold undercover report 13, Victorian Department of Primary

Industries, 43p.

Leaman, D. E., and Richardson, R. G., 2003. A geophysical model of the major

Tasmanian granitoids. Tasmanian Geological Survey Record 2003/11, 8p.

Murphy, B., Denwer, K., Keele, R., Stapleton, P., Korsch, R., Seymour, D., and

Green, G., 2002. Tasmania Mineral Province Geoscientific database, 3D Geological

Modeling; Mines and Mineral Prospectivity Project T3: Release Notes, 83p.

Seal, R. R. and Foley, N. K., 2002, Progress on Geo-environmental Models for

Selected Mineral Deposit Types: U.S. Geological Survey open-File Report 02-195,

213p.

Singer, D.A., 2007. Short Course Introduction to Quantitative Mineral Resource Assessments. USGS Open-File Report 2007-1434, 13p. Singer, D.A. and Berger, V.I., 2007. Deposit Models and Their Application in Mineral Resource Assessments. Mineral Resource Assessment Methodologies, USGS Circular 1294, 71-78.

APPENDIX 1, EXAMPLE MINERAL DEPOSIT MODEL Agvein_1: SILVER-BEARING POLYMETALLIC VEINS (Based on Model 22c by Cox and Singer, 1986) Model Description Approximate Synonyms: Felsic intrusion-associated Ag-Pb-Zn veins. DESCRIPTION: Quartz-carbonate veins with base metal sulfides and Ag, ± Au ± tin related to hypabyssal granitic intrusions in sedimentary, igneous and metamorphic terranes. General References: Sangster, 1984. GEOLOGICAL ENVIRONMENT Rock Types: Veins related to calc-alkaline to alkaline, diorite to granodiorite, monzonite to monzogranite in small intrusions and dyke swarms in sedimentary, igneous and metamorphic rocks. Sub-volcanic intrusions, necks, dykes, and plugs of andesite to rhyolite composition. Textures: Granitic texture, fine- to medium-grained equigranular and porphyro-aphanitic. Age Range: Any age. Depositional Environment: Near-surface fractures and breccias within the thermal aureoles of intrusions. In some cases peripheral to porphyry systems. Tectonic Setting(s): Continental margin and island arc volcanic-plutonic belts, especially zones of local domal uplift. Associated Deposit Types: Tin/tungsten veins, mesothermal gold veins, Sn-Au-polymetallic veins, Porphyry Cu-Mo, Porphyry Mo low-F, disseminated tin, polymetallic replacement, skarns, epithermal deposits, greisens, etc. DEPOSIT DESCRIPTION Mineralogy: galena + sphalerite + pyrite ± tetrahedrite-tennantite ± chalcopyrite ± arsenopyrite ± Ag sulfosalts ± argentite ± Cu -Pb sulfosalts ± in veins of quartz + siderite + calcite ± ankerite/dolomite ± chlorite ± rhodochrosite. Texture/Structure: Complex, multiphase veins with breccia, comb structure, crustification, and less commonly colloform textures. Textures may vary from vuggy to compact within mineralized systems. Alteration: Generally wide propylitic zones and narrow sericitic and argillic zones, but may be small or non-existent. Some silicification of carbonate rocks to form jasperoid. Some quartz-carbonate-sericite alteration of ultrabasics.

Ore Controls: Areas of high permeability, intrusive contacts, fault intersections, and breccia veins and pipes. Replacement ore bodies may form where structures intersect carbonate rocks. Weathering Gossans and Fe- Mn-oxide stains. Zn and Pb carbonates and Pb sulfates, arsenates and phosphates. Abundant quartz chips in soil. Supergene enrichment produces high-grade native and horn silver ores in veins where calcite is not abundant. Geochemical Signature Zn, Cu, Pb, As, Ag, Mn, Ba. Anomalies zoned from Cu-Au outward to Zn-Pb-Ag to Mn at periphery. EXAMPLES Misima I., PPNG (Williamson and Rogerson, 1983) St. Anthony (Mammoth), USAZ (Creasey, 1950) Wallapai District, USAZ (Thomas, 1949) Magnet, AUTS Cox (1975)

Known Deposits and Mineral Prospects in Tasmania

Most silver bearing Ag-Pb-Zn sulphide vein deposits in Tasmania form the outer haloes of zoned mineral fields around Devonian granitoids. The best known of these is the Zeehan field. Similar zoned occurrences are reported at Mt. Bischoff-Heazlewood, Moina-Round Hill, and at Scamander in eastern Tasmania (Collins et al, 1989).

In the Zeehan field the veins occupy a complex system of faults and fractures, apparently related to mid-Devonian deformation. The veins trend between NNW and NNE and intersect rocks of late Proterozoic to Early Devonian age, though most are in the Neoproterozoic Oonah and Crimson Creek formations.

In the Dundas field the veins occupy fractures in late Proterozoic and Cambrian rocks (including ultrabasics). However, some of these are apparently replacement bodies.

Along the northern flank of the Meredith Granite, some copper, lead and zinc vein occurrences form a NNE trending zone. The Magnet Ag-Pb-Zn mine is the largest of these deposits, producing 0.6 Mt of ore (37,0000 t of lead, 8 Moz of silver and an unknown quantity of zinc). It is located midway between the Cleveland and Mt Bischoff tin deposits, and the orebody occupies a steep west-northwest dipping fracture system within an up-thrust, early Cambrian mafic/ultramafic mass. The ore-shoot is developed at the intersection of two major fractures (Cox, 1975).

In the Moina area most of the Ag-Pb-Bi-Au-Sn-W mineral occurrences are related to and centred on the Dolcoath granite. The largest of the Pb-Ag-Zn veins is in the Round Hill mine where crudely-shaped saddle reefs are formed in the crests of asymmetrical, northwest-trending anticlines in the Moina sandstone (Collins et al, 1989).

Geophysical studies show that most of Pb-Ag-Zn deposits are located within the 4 km depth contour of the Heemskirk granite. A similar pattern is observed with respect to the Granite Tor granite near Rosebery, where the occurrences are also located within the 4 km depth contour. However, the role of NNE trending Henty Fault in the localisation of these veins is also important. Geophysical studies have established that the Granite Tor Granite is a large body at shallow depth, and that only a small

part of the granite is exposed at Granite Tor. Two shallow ridges of the granite extend to the WSW from Granite Tor, and NE from Mt Pelion to the Dolcoath Granite (Taheri and Green, 1990). The WSW-trending granite ridge extends from the Granite Tor Granite to the Pine Hill Granite, and possibly as far west as the Heemskirk Granite.

The silver bearing lead-zinc veins in western Tasmania can be interpreted to form two separate NNE trending zones: the first one extends between the Meredith granite and the Housetop granite and the second trends along a ridge between the Heemskirk granite in the west to the Dolcoath granite in the east.

In the Northeast Element, there are a few known occurrences of lead-zinc veins, including the Paul Beahrs, Yarmouth, Scamander Bell and North Scamander prospects. All are associated with Devonian granites of the Scamander Tier, and form the outer zone of a zoned Sn-W-Cu-Pb-Zn-Ag field (Groves, 1972).

Assessment Criteria

1. Distribution of Devonian granitoids. 2. Aeromagnetic and gravity data supporting the subsurface distribution of Devonian

granites. In particular the granite depth contour of 6km is important in assessing the prospectivity of the zones around granites.

3. Presence of major faults and fractures and rocks susceptible to brittle deformation. The presence of other suitable structures such as folds and breccia zones could be important within individual mineral fields.

4. Distribution of known mineral occurrences.

Assessment: Tract BM5a/H/B-D The tract includes Devonian granites of north-western Tasmania. The granites form two NNE trending zones along the subsurface extension of granitoids. The area within the 6 km depth contour of the granite surface marks the width of the delineated zone around granites. Geophysical data indicate that the subsurface extension of the granites continues under Post Palaeozoic rocks in the Tasmanian Basin. The tract also includes the known lead-zinc mineral fields and has a high certainly level. This tract also includes the area around the Pieman granite in the Rocky Cape Element, Granite Tor to Barn Bluff in the Tyennan Element, and the Penguin-Sheffield area. These regions have a moderate to high certainty level.

The tract also includes Devonian granite areas in the Northeast Tasmania. Again the 6 km depth contour of the granite surface has been used to extend the tract around exposed bodies of granite. The area includes the known occurrences of lead-zinc veins in the zoned Sn-W-Cu-Pb-Zn-Ag mineral field in the Scamander area.

Based on the available information this part of the tract has a high potential for silver bearing lead-zinc vein deposits with a high certainty level.

Assessment: Tract BM5b/M/B-C This tract is in the Tyennan Element and includes poorly exposed Devonian granites in the area. In this tract also, the 6 km depth contour of the granite surface has been used to extend the tract around exposed bodies of granites. No deposits of this style are known in the area. The tract also includes the known occurrences of lead-zinc veins in the Mt Mueller area (although the relationships to granite are uncertain).

Based on the available information the tract has a moderate for silver-lead-zinc vein deposits potential with a moderate to high certainty level.

Economic Significance

The silver-bearing lead-zinc veins have been mined for lead, zinc, copper and silver. Some deposits have also served as important source for gold. Global grade and tonnage data shows that 90% of deposits contain more than 290 tonnes, 50% contain more than 7600 tonnes and 10% contain more than 200,000 tonnes of ore. In 90% of deposits the ores contain >140 g/t silver, and >2.4% lead. In 50% of deposits the ores contain >820 g/t silver, >0.13 g/t gold, >9% lead, and >2.1% zinc and > 0.89% copper. The richest 10% of deposits contain >4700 g/t silver, >11 g/t gold, >33% lead, >7.6% zinc and >0.89% copper.

APPENDIX 2. DEPOSIT TYPE WEIGHTINGS

An important component of the prospectivity analysis is the weighting of each deposit

model to reflect its importance in the Tasmanian context. In the 1996 RFA the expert

review panel of 6 geologists subjectively ranked each deposit type on a scale of 1-10

to reflect to produce a “Deposit Size Index” (Green and Jarieth, 1996). We initially

planned to use these weightings in our analysis, however, it became obvious that

there were problems with the assigned weightings:

1. Weightings were not assigned to all deposit types (particularly the industrial

mineral deposit types).

2. Some deposit types not previously recorded in a Tasmanian context were

given weightings higher than those of deposit types for which there had been

operating mines (e.g., Besshi Cu vs Sn-BMS-Au veins).

3. There were a very wide range of weightings assigned by individual experts to

a given deposit type, e.g. 0.4-9 for the sediment-hosted Cu model. The 1996 expert

panel attempted to account for this by removing outliers (low-scores) and averaging

the remaining values.

We concluded that as it was not entirely apparent what was being ranked, and that

that the ranking was being applied consistently, a new method of deriving weightings

was required. The scheme we have used is based on 3 questions:

1. What is the probability a particular deposit type is present in Tasmania? We

have based our assessment on the presence of a particular style of mineralisation in

Tasmania (partly a function of how successful previous exploration has been and/or if

exploration has targeted a particular ore type). This factor is described as “relevance

to Tasmania” and was scored between 0 and 6 (see table A1). Note that we

differentiate those mineral deposits which are of sufficient economic size to be mined

(score 5) from those which are “World Class” (Singer, 1995) i.e., have metal contents

that are in the top 10% of mineral deposits globally (score 6).

2. An indication of the likelihood a deposit of a particular type would be mined –

an “Economic” score (between 1 & 3) that reflects grade, tonnage and cost/ease of

processing a particular deposit type, based largely on experience of Tasmanian

deposits but considering deposits of that style elsewhere in Australia, or globally, if

there are no known examples elsewhere in Australia.

3. The probability that, using modern technology a particular deposit type can be

located (within its economic depth range). This “findability” score (1-3) represents our

ability to use geological, geochemical and geophysical data to locate a particular

deposit type.

Scores were after discussions involving Prof Ross Large, Dr Geoff Green (MRT) and

Assoc. Prof. Andrew McNeill and we believe that they, in particular the “Relevance to

Tasmania” and “economic” scores, provide a much less subjective weighting than that

allocated by the 1996 Expert Panel. In Table A2, all 3 scores are added to produce a

final weighting that ranges from 2 to 11 (possible minimum =2 and maximum =12).

Also included on Table A2 for reference are examples of individual deposit types that

are known in Tasmania (largely derived from the Mineral Deposit Models and Bacon

et al (2008)) and the in-ground value (in AU$) of a tonne of ore from each deposit

type, which is based on:

1. Commodity prices as at 3 October 2011 which have been sourced from, for

metals, the London Metals Exchange, Kitco, Index Mundi and Infomine websites, and

for industrial minerals, on advice from Industry professionals.

2. Ore grades derived from (in order of preference) typical Tasmanian deposits,

deposits from elsewhere in Australia, deposits elsewhere in the world, or average

global deposit grades. References to the sources for all grade data are provided.

Note that for some deposit types, particularly alluvial placer deposits which were

mined in Tasmania predominantly in the late 19th and early 20th Centuries, it has been

difficult to obtain grade data and therefore we have been forced to use average global

grades.

It should be noted that as discussed in Green and Jarieth (1996) using “in-ground”

values for the different deposit types is not considered to be a useful indicator of

prospectivity because of:

1. The differences between in-ground and extracted values (i.e., “in-ground”

values reflect only the value of the metal in a tonne of ore, and do not include factors

such as mining costs, metallurgical losses or the cost of processing or refining to

produce a final saleable product).

2. The volatility in metal prices and exchange rates (e.g., The Rosebery

polymetallic VHMS deposit had an in-ground value of AU$17.5 billion in 2003 but

AU$47.6 Billion in 2006).

Table A1 Criteria for assigning weightings

score Relevance to Tasmania Economic score Findability score

0 not known, geology permissible

1 not known, geology very favourable commonly small resources relatively difficult to find

2 minor occurrences only commonly moderate resources moderately difficult to find

3 significant deposits known commonly large resources of good grade good findability characteristics

4 significant deposits, mined or under development

5 multiple deposits, mined economically

6 multiple deposits of world class

Table A2 Weightings, Example deposits and in-ground values for Deposit Models considered in this review

Deposit Model Relevance Size/grade Findability total weighting Tasmanian Examples

AU$

value/t Deposit Source

Ag bearing polymetallic veins 2 2 2 6 Mt Farrell district, Salmons Vein 727 Mt Farrell (Tas) Seymour et al (2006)

Au assoc with Alkaline

Intrusives

2 1 1 4 Cygnet 46 Cadia (NSW) Cook et al (2007)

Placer Au 2 1 2 5 Lisle 40 Global average Cox and Singer (1986)

Au-BM-Sn veins 2 1 2 5 Lakeside 192 Lakeside (Tas) Seymour et al (2006)

Avebury-style Ni 4 2 2 8 Avebury 190 Avebury (Tas) Seymour et al (2006)

Bauxite 2 1 3 6 Ouse, Myalla 566 Gove (NT) Ferenczi (2001)

Besshi type Massive Sulphide 0 1 1 2 196 Global average Franklin et al (2005)

Metalliferous black shales 1 2 2 5 Cowrie Siltstone? 61 Talivaara (Finland) Large (2011)

Sediment hosted Au (Carlin

Type)

1 3 1 5 Brookside? 319 Carlin (USA) Cline et al (2005)

Placer Cr 2 1 2 5 Adamsfield, Barnes Hill 87 Global average Cox and Singer (1986)

Basaltic Cu 0 2 1 3 66 Keweenaw/Calumet (USA) Weege and Pollock (1972)

Epithermal Au-Ag 0 2 1 3 577 Pajingo (QLD) Bobis et al (1995)

Synorogenic nickel-copper

deposits

1 3 1 5 Cuni, Gennett's Winze 392 Cuni (Tas) Seymour et al (2006)

Geothermal Energy 2 2 1 5 Fingal, Lemont

W-Sn-Cu-magnetite skarns 4 2 3 9 Mt Lindsay, St Dizier, Kara 250 Mt Lindsay (Tas) www.ventureminerals.com.au

Sn greisen 3 1 2 6 Anchor 61 Anchor (Tas) Seymour et al (2006)

Au in Ironstones 1 2 2 5 Savage River 346 Starra (QLD) Williams (2005)

Irish-style base metal 3 2 1 6 Oceana, Grieves Siding 269 Oceana (Tas) Seymour et al (2006)

Lateritic Ni 3 2 2 7 Barnes Hill 176 Barnes Hill (Tas) www.protoresources.com.au

Au assoc with VHMS 4 2 2 8 Henty 680 Henty (Tas) Seymour et al (2006)

Polymetallic style VHMS 6 3 2 11 Rosebery, Hellyer, Que River 594 Rosebery (Tas) Unpub. MMG data

Ni associated with Jurassic

dolerite

1 1 1 3 Forster 917 Noril'sk (Russia) Naldrett (2009)

Alluvial Sn 3 1 2 6 Cox Bight, Ringarooma River 26 Global range Garnett & Bassett (2005)

Mt Lyell type Cu-Au 5 2 3 10 Mt Lyell cluster of deposits 120 Mt Lyell (Tas) Seymour et al (2006)

REE 2 1 1 4 Naracoopa, Ocean Beach, Scotia 982 Global average Cox and Singer (1986)

Proterozoic magnetite skarn 5 2 3 10 Savage River 59 Savage River (Tas) Seymour et al (2006)

Slate Belt Au 4 1 2 7 Beaconsfield, Lefroy 1,033 Beaconsfield (Tas) Seymour et al (2006)

Replacement Sn 6 2 2 10 Renison, Mt. Bischoff, Cleveland,

Severn

305 Renison (Tas) Seymour et al (2006)

Sn-W-Mo veins 3 1 2 6 Foley Zone (Cleveland) 268 Foley Zone (TAS) Seymour et al (2006)

Early Cambrian Ultramafic-

related Ni

1 2 1 4 106 Duluth (USA) Naldrett (2009)

Sandstone-hosted U 1 2 1 4 Castle Carey Creek 323 Global Average Cox and Singer (1986)

Coal 3 1 2 6 Fingal Valley, Hamilton 127 Fingal (Tas) Bacon et al (2008)

Dolomite 3 1 2 6 Weld River, Cressy, Smithton 30 Tasmania Morrison, pers comm. (2011)

Limestone 4 2 2 8 Railton, Mole Creek, Flowery Gully 35 Flowery Gully (Tas) Quote; crushed limestone

Magnesite 3 2 2 7 Lyons River, Main Creek, Savage

River

1,369 Arthur River (TAS) Seymour et al (2006)

Ochre 2 1 1 4 Bowry Creek

Oil Shale 2 2 1 5 Mersey Valley, Poatina, Maydena,

OonahShoreline placer Ti 2 1 2 5 Naracoopa, Ocean Beach 22 Naracoopa Seymour et al (2006)

Silica Flour 5 1 3 9 Corinna, Blackwater, Hawkes Creek 550 Corinna H. Nolan pers comm. (2012)

Zeolites 2 1 1 4 Gads Hill, Marrawah 30 Gads Hill/US production Bacon et al (2008); minerals.usgs.gov/minerals/

Silica Hard rock 2 1 1 4 Beaconsfield, Glovers Bluff

Dimension stone 2 1 2 5 Nunamarra, Buckland Not considered in detailed prospectivity analysis

Construction - hard rock 2 1 2 5 Flagstaff Gully, Kindred Not considered in detailed prospectivity analysis

Construction - sand, gravel,

clay

3 1 3 7 Tonganah, Railton, South Arm Not considered in detailed prospectivity analysis

Cobar Style Cu+/-Au, Zn, Pb 2 2 1 5 Balfour District 274 CSA (NSW) Lawrie and Hinman (1998)

REFERENCES:

Bacon, C.A., Calver, C.R., and Pemberton, J., 2008. The industrial mineral deposits of Tasmania. Geological Survey Mineral Resources Report 13, 48p.

Bobis, R.E., Jareith, S., Morrison, G.W., 1995. The Anatomy of a Carboniferous Epithermal Ore Shoot at Pajingo, Queensland: Setting, Zoning, Alteration, and Fluid Conditions. Economic Geology, 90:1776-1798.

Cline, J.S., Hopstra, A.H., Munteau, J.L., Tosdal, R.M., and Hickey, K.A., 2005. Carlin-Type Gold Deposits in Nevada: Critical Geologic Characteristics and Viable Models. Economic Geology 100th Anniversary Volume, pp. 451-484.

Cook, D.R., Wilson, A.J., House, M.J., Wolfe, R.C., Walshe, J.L., Lickfold, V., and Crawford, A.J., 2007. Alkalic porphyry Au – Cu and associated mineral deposits of the Ordovician to Early Silurian Macquarie Arc, New South Wales. Australian Journal of Earth Sciences, 54: 445-463.

Cox, D.P., and Singer, D.A., 1986. Mineral Deposit Models, USGS Bulletin 1693, 379p.

Ferenczi, P., 2001. Iron ore, manganese and bauxite deposits of the Northern Territory. NT Geological Survey Report 13, 113pp.

Franklin, J.M., Gibson, H.L., Jonasson, I.R., and Galley, A.G., 2005. Volcanogenic Massive Sulfide Deposits. Economic Geology 100th Anniversary Volume, pp. 523-560.

Garnett, R.H.T., and Bassett, N.C., 2005. Placer Deposits. Economic Geology 100th Anniversary Volume, pp. 813-843.

Index Mundi; http://www.indexmundi.com/commodities/

Infomine – mining intelligence & technology; http://www.infomine.com/

Kitco Metals; http://www.kitcometals.com/

Lawie, K.C., and Hinman, M., 1998. Cobar-style polymetallic Au-Cu-Ag-Pb-Zn deposits. AGSO Journal of Australian Geology and Geophysics, 17 :169-187.

London Metals Exchange; http://www.lme.com/services.asp.

Naldrett, A.J., 2009. Fundamentals of Magmatic sulfide deposits, in Li, C and Ripley, E.M., (eds.) New developments in magmatic N-Cu and PGE deposits, Geological publishing House, Beijing, pp. 1-26.

Seymour, D., Green, G.R., and Calver C.R., 2006. The Geology and Mineral Deposits of Tasmania: a summary. Mineral Resources Tasmania, Geological Survey Bulletin 72, 29pp.

Singer, D.A., 1995. World class base and precious metal deposits - A quantitative analysis, Economic Geology 90:88-104.

Weege, R.J., and Pollock, J.P., 1972. The Geology of Two New mines in the Native Copper District of Michigan. Economic Geology, 67:622-633.

Williams, P.J., Barton, M., Johnson, D.A., Fonbote, L., de Haller, A., Mark, G., Oliver, N.H.S., and Marschik, R., 2005. Iron Oxide Copper-Gold Deposits: Geology, Space-Time Distribution, and Possible Modes of Origin. Economic Geology 100th Anniversary Volume, pp. 371–405.

APPENDIX 2 MINERAL POTENTIAL MAPS

Individual tract maps were prepared for the 45 Ore deposit Models used in this

analysis (see Figure A1 for an example). For the analysis 42 of these tract maps

(excluding dimension stone and construction materials deposit models) were

superimposed to produce a series of mineral prospectivity maps:

1. ‘Composite’ mineral potential map. A given area’ is assigned the value of the

highest potential mineral deposit model relevant to that particular area. For

example if three models are relevant and have potentials of 18, 12 and 2, the area

will be assigned a potential of 18 (high).

2. ‘Weighted composite’ mineral potential map. A value is assigned to each area

by multiplying the highest mineral potential by the deposit type weighting (see

Appendix 1). The range of calculated values ranges from 0 (no potential for any

deposit type) to 198 (for areas that have a high potential for polymetallic VHMS)

3. ‘Cumulative’ mineral potential map. The cumulative, or summed, mineral

potential of a given area. In the example used above, the area will be assigned a

value of 18+12+2 = 32. In practice this yields a value between 0 and 224.

4. ‘Weighted cumulative’ mineral potential map. A value for each area is obtained

by multiplying the mineral potential by the deposit type weighting (see Appendix 1).

For example polymetallic VHMS deposits have been assigned a deposit type

weighting of 11. Areas of high potential for these deposits would therefore have a

weighted score of 18 x 11 = 198. The weighted cumulative score for a polygon is

then calculated by summing the weighted scores for all relevant mineral deposit

models. This yields a value ranging between 0 and 1608.

For this analysis we initially focussed on the composite, cumulative and weighted

cumulative mineral potential maps (Figures A2-4). However during the

assessment it became obvious that there was, as might be expected, a very good

correlation between weighted cumulative and cumulative scores (Figure A5) and

that there was no obvious advantage in using the weighted cumulative results over

the less ‘derived’ cumulative results. Final interpretation therefore relied largely on

the composite and cumulative mineral potential maps

Figure A1, Example of a tract map, in this case for Polymetallic VHMS deposits in

the Cambrian Mount Read Volcanics. Numbers (1-7) refer to major strato-tectonic

elements of Tasmanian geology.

Figure A2, Composite mineral potential map

Figure A3, Cumulative mineral potential map

Figure A4, Weighted Cumulative mineral potential map.

Figure A5, Comparison of cumulative and weighted cumulative potential scores,

subdivided by assessed mineral potential. There is a good correlation with a

straight line fit and r2=0.98.

0 50 100 150 200 250

Maximum cumulative Prospectivity score

0

400

800

1200

1600

2000

Maxim

um

weig

hte

d c

um

ula

tive p

rosp

ecti

vit

y s

co

re

Assessed Mineral PotentialVery high

High

Low-moderate

Appendix 3. Summary of reserve areas assessed to have very high prospectively

155 Black Bluff - Cambrian Mt Read Volcanics (MRV) & Ordovician Carbonates with

Size: 0.2 km2 thin cover of Tertiary basalt. High potential for VHMS and Sn-W-F

Skarn and vein systems. (Score = 224)

88 West Coast Range - Cambrian MRV and Owen Conglomerate. Overlaps Rosebery

Size: 19.4 km2 Mine lease. Excellent potential for VHMS. (Score = 216)

146 Dove River - Mt Read Volcanics overlain by Tertiary Basalt; also close to

Size: 3 km2 Devonian granite. Potential for VHMS and granite vein systems.

(Score= 204)

144, 152, 176, Black Bluff- Cambrian MRV and Ordovician limestone and sandstone. Both

Size: 106.2 km2 VHMS and granite-related vein/skarn Potential. (Score=200)

89 West Coast - Cambrian MRV, overlaps both Rosebery and Henty mine leases.

Size: 2km2 High VHMS potential. (Score=198)

187 Mt Roland - Ordovician Sandstones. Potential for MRV at depth, and granite

Size: 9.5km2 related veins. (Score=196)

198 Tarkine East - Includes MRV to Neoproterozic sedimentary rocks, plus

Size: 372km2 ultramafics. Covers mining leases at Que River and Hellyer, Very

High potential for VHMS but also Sn-W and slate belt gold in other

part. (Score=188)

Comment: Large area should be divided into high and low

potential.

104, 101 Tarkine East - Cambrian MRV and within Devonian granite halo. Potential for

Size: 5.5 km2 VHMS and Sn-W veins/skarn (Score=178)

196 Leven Canyon - Cambrian VHMS and Gordon Group Limestones. Potential for

Size: 10.5 km2 VHMS, skarns and limestone. (Score=166)

140 Dove River - Cambrian VHMS, Cambrian granite. Potential for VHMS and

Size: 5.4 km2 granite related veins and skarn. (Score=162)

81 Henty - Variable geology from Proterozoic to Siluro-Devonian. Includes

Size: 101 km2 (large area) Avebury Nickel leases. Potential for Nickel, granite related Sn-W

and carbonate hosted Pb-Zn (Score=160)

149, 102, 111 Tarkine South - Neoproterozoic to Permian – very variable geology. Includes

Size: 260.5 km2 Savage River Fe Mine and Mt Lindsay Sn-W-Fe skarn (new

development in feasibility). Potential for Skarn Fe, Skarn Sn-W,

magnesite and silica flour (Score=160)

252 Tarkine North Neoproterozoic overlain by Permian sediments. Includes Keith &

Size: 603 km2 Arthur River magnesite deposits and overlaps Savage River Mine

Lease. Potential for magnesite, Fe-skarn, silica flour and dolomite.

(Score=157)

Comment: Large area should be divided, based on mineral

potential

158 Mt Roland - Cambrian MRV and within Devonian granite halo. Potential for

Size: 1.2 km2 VHMS and granite-related veins. (Score=154)

87 Eastern Tiers - Predominantly Mesozoic rocks overlying Sn-W prospective rock

Size: 37km2 types. Also geothermal potential. (Score=108)

160 Black Bluff - Tertiary basalt overlying MRV & Granite halo. Potential for VHMS

Size: 0.3km2 & granite vein systems. (Score=150)

191, 192, 199 Old Park - Halo of Housetop granite. Includes Kara Mine leases.

Size: 10.6km2 Fe & W Skarn potential. (Score=147)

171 Tarkine East - Overlaps Mr Bischoff Tin mine leases. Potential

Size: 2.6km2 for Skarn replacement Sn & W. (Score=147)

90, 85 Heemskirk - Granite halo and Oonah Formation. Potential for Sn

Size: 2.4km2 Skarn. (Score=131)

52 West Coast - Cambrian to Devonian including the MRV. Potential for

Size: 95km2 (needs dividing) VHMS, slate belt Au and Irish Zn-Pb. (Score=128)

92 West Coast - Crimson Creek and Success Creek Groups. Overlaps Renison

Size: 1.4km2 Mine lease and granite halo. (Score=180)

99, 100 Tarkine East - MRV and partly in granite halo. Potential for VHMS and Sn-W veins

Size: 0.3km2 (Score=124)

229 Emu River -Devonian granite. Potential for Sn-W greisen vein system.


249, 254 Flowerdale - Neoproterozoic with Permian and Tertiary cover. Includes Meunna

Size: 26.5km2 Hills hand rock Silica deposit. Also potential for magnesite and silica

flour. (Score=121)

183 Leven Canyon - MRV and Cambro-Ordovician rocks. VHMS potential &

Size: 6.5km2 lesser Sn-W potential. (Score=126)

151 Mt Roland - Ordovician Conglomerate plus Gordon Group limestones with

Size: 0.9m2 granite halo. Skarn and VMS potential. (Score=116)

136 Great Northern Tiers - Neoproterozoic to Siluro-Devonian Sediments. Includes

Size: 35.1km2 (Needs to be divided) Cambrian granite. Potential for Limestone, VHMS

& base metal vein systems. (Score=114)

148 Mt Roland - MRV overlain by Gordon Limestone - VHMS & Limestone

Size: 3.7km2 potential. (Score=112)

69, 80 West Coast - MRV plus Siluro-Devonian Sediments. VHMS and slate belt

Size: 31km2 Au potential. (Score=109)

143 Tarkine South - Neoproterozoic. Savage River Fe potential and Besshi Cu.


50 West Coast - MRV and Owen Conglomerate. Potential for VHMS & Slate

Size: 4.6km2 Belt Au. (Score=104)

132 Dove River - Neoproterozoic metamorphics and Cambrian granite.

Size: 2.3km2 Cambrian vein systems. (Score=104)

118 Ben Lomond - Devonian granite intruding Mathinna Beds. Potential for

Size: 0.5km2 Sn-W veins, slate belt Au & geothermal. (Score=98)

244 Tarkine North - Neoproterozoic sedimentary rocks. Includes the Nelson

Size: 51.8m2 River magnetite mining lease. Granite halo, magnetite skarn,

Cobar style base metals. (Score=91)

167, 168 Tarkine East - Tertiary basalt over Neoproterozoic and within granite halo.

Size: 0.8km2 Granite related vein potential. (Score=86)

126, 127, 177 Ben Lomond - Devonian granites intruding Mathinna Beds. Greisen

Size: 55.9km2 Sn-W – Mo Veins, slate belt Au and geothermal potential.

(Score=81)

87 Eastern Tiers - Mesozoic sediments on Mathinna beds & Devonian granite.

Size: 37km2 Granite halo vein potential and geothermal potential.

(Score=80)

25 Huon Forests - Large area – needs to be split to exclude areas with potential for

Size: 603 km2 industrial minerals, silica flour and dolomite. High quality dolomite

has been identified and needs to be available for mining.

(Score =73)

239 Dazzler Range - Covers the Barnes Hill Ni laterite deposit and construction

Size:59.8 km2 stone resources. Needs to be available for development.

(Score=75)

137 Ben Lomond - Greisen Sn, Sn-W veins and slate-belt gold potential.

Size: 25.3km2 (needs to be divided) (Score=70)

79 West Coast - Owen Conglomerate, Gordon Limestone & Eldon Group

Size: 6.2km2 sedimentary rocks. Potential for Limestone and

Irish Style Zn-Pb. Includes Oceana deposit RL. (Score=70)

59 West Coast - Contains some MRV Cambrian sediments and Eldon Group.

Size: 11.6km2 (needs to be divided) Potential for VHMS. (Score=67)

156 Ben Lomond - Mathinna beds overlain by Triassic and intruded by Jurassic

Size: 29.4km2 dolerite. Includes some coal leases. Potential slate belt gold, coal

Geothermal. (Score=63)

268 Shakespeare Hills - Neoproterozoic with Tertiary basalt cover. Includes

Size: 45.8km2 Mining leases and retention licence for hard rock silica.

(Score=61)

208, 184 North East - Mathinna beds, Devonian granite and cover rocks. Potential

Size: 184.7km2 for slate belt gold & covers Mathinna Trend gold zone.

(Score=59)

129, 150 147 St Marys - Devonian granite, Triassic Coal measures & Permian

Size: 34.8km2 Sediments. Mining leases & retention licences for Coal.

Also slate belt gold potential. (Score=52)

123, 93 Douglas Apsley - Triassic, intruded by Jurassic dolerite. Covers coal leases

Size: 164.4km2 & retention licences. Coal and geothermal potential.

(Score=38)

225, 226 Mt Arthur - Mathinna Beds & Devonian Granite. Includes Lisle

Size: 17.9km2 Goldfield & associated mining leases. Slate belt gold

Potential. (Score=40)

232 Port Sorell - Neoproterozoic sedimentary rocks overlain by Tertiary sands.

Size: 3.3 km2 Leases for strategic sand resources. Needs to remain available for

development. (Score=17)

End of very high potential Reserve areas.

APPENDIX 5, STRUCTURE OF IGA AREAS GEOLOGY COMMENTS CODES COMPLETED_V4.XLS

If highlighted in red, in the spreadsheet, the proposed reserve area encompasses

tracts of variable assessed mineral potential and the area may need to be

subdivided to account for that variability.

Column Header Explanation

A Final code Proposed reserve number

B Final Name Proposed reserve district

C Final area Area (in Sq. Km) of proposed reserve

D Basement Geology Lithological codes from MRT 1:250,000 geological map sheets

E Comments Relating to geology or prospectitiy

F Known mineralisation Proximity to known deposits or mineralised trends

G Mining Leases/retention licences Mining tenements which intersect the reserve polygon

H MaxPoten Maximum composite mineral potential score

I Max total score Maximum cumulative mineral Potential score

J Max weighted score Maximum weighted composite mineral potential score

K Max total weighted score Maximum weighted cumulative mineral potential score

L Top 4 deposit models Models with highest potential (only scored if potential >=2)

M Assessed Maximum Potential Low-moderate, high or very high as discussed in 3.4

minerals prospectivity assessment: … prospectivity assessment: proposed reserve areas ... (termed...

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