Department for Manufacturing, Innovation, Trade, Resources and Energy Mineral Systems Research in South Australia Mineral Systems Workshop 1-3 rd July 2013 Martin Fairclough & Simon van der Wielen

Outline 2 Changing Role of the Geological Survey Mineral Systems and Mineral Potential Mapping Research in GSSA Examples DETCRC Projects GSSA Projects Issues

Changing Role of the Geological Survey 3 Driven by changes in the economic and political environment requirement to be more aligned to resource industry requirements (partly in response to changes in the industry) going beyond just precompetitive data, but actually focusing on value-adding to create more downstream exploration datasets (and concepts)

Mineral Systems & Mineral Potential Research Significant PIRSA (now DMITRE) involvement in pmd*CRC (including one on one projects) and post CRC projects with CSIRO Establishment of an “Exploration Geology Group” (EGG) in GSSA 2007 – produced a range of “key ingredients maps for commodities grouping deposit models) Chiropractic re-alignment of GSSA to form a dedicated Mineral Systems Team (2011). Process-driven approach 4

Mineral Systems & Mineral Potential Research GSSA has been utlising the Five (or more) Questions approach for years – we just haven’t called it that! Very much a process-driven approach, particularly steering away from prescriptive ore-deposit model nomenclature (e.g IAEA), even though we still use the latter for communication purposes The Mineral Systems team focuses on the task of understanding the processes, and in conjunction with the Mapping and Modeling teams, translating the critical processes to mapable elements (or proxies) 5

Case study - DETCRC Emmie Bluff – reverse engineering an IOCG to understand that alteration system (targeting elements) and generating mapable criteria Geochemical trends in IOCG alteration - new data from the Gawler Craton (Adrian Fabris) Geochemical sampling protocol and initial results from the Emmie Bluff case study Exploration strategies for IOCG mineral systems under deep cover (Simon van der Wielen) IOCG exploration strategy and initial results Emmie Bluff case study 6

Workflow

1x vertical exaggeration 60 km 9.8 km N Geological Surfaces 52 km Emmie Bluff 3D Model Emmie Bluff 8 – Mulgathing Complex 5 – Wallaroo Group 0 – DEM Surface 1 – Neoproterozoic 2 – Gairdner Dyke Swarm 4 – Gawler Range Volcanics 3 – Pandurra Formation 6 – Donington Suite 7 – Hutchinson Group Listric Faults Vertical Faults

10x vertical exaggeration 10 km 2 km N Geochemistry Data 10 km Emmie Bluff 3D Model Emmie Bluff Sericite Hematite Magnetite Hematite – Magnetite K-Feldspar Albite Sericite – Chlorite Chlorite

10x vertical exaggeration 10 km 2 km N Hylogger Data 10 km Emmie Bluff 3D Model Emmie Bluff Sericite Composition Muscoviti c Phengiti c

10x vertical exaggeration 10 km 2 km N Alteration Voxet 10 km Emmie Bluff 3D Model Emmie Bluff Sericite Hematite Magnetite Hematite – Magnetite K-Feldspar Albite Sericite – Chlorite Chlorite 500 m x 500 m x 10 m cell size

Key Learnings from Emmie Bluff Case Sample spacing for proposed pattern drilling program Sampling strategy (unconformity vs sampling into the basement) Has the current drilling tested the Emmie Bluff IOCG system?

Geochemical IOCG Prospectivity Index Elements associated with IOCG mineral systems Based on 10x crustal abundance Can distinguish proximal from distal alteration Independent of host lithology See poster and Adrian Fabris in foyer 13

14 Olympic Dam Carapateena M ODELING THE MAPABLE ELEMENTS – PUTTING IT TOGETHER Alteration (DETCRC) and geophysical modeling of IOCG systems S. van der Weilen, L. Katona and A. Fabris Australian Copper Conference, June th 2013 Martin Fairclough, Geological Survey of SA

15 New Data Collection To Further Test Modeling Concepts Australian Copper Conference, June th 2013 Martin Fairclough, Geological Survey of SA

Case study 2 16 All IOCGs in South Australia are elevated in uranium, as are large parts of the surrounding host rocks (“the reservoir”). No significant elevated uranium older than ca Ma However, considerable examples of anomalous (some economic) uranium throughout younger rocks (such as Beverley, possibly active very recently) So the fluid pathways and drivers are working well also What about other traps? “uncomformity-related” just to give one possibility a name.

Case study 2 17 All IOCGs in South Australia are elevated in uranium, as are large parts of the surrounding host rocks (“the reservoir”). No significant elevated uranium older than ca Ma However, considerable examples of anomalous (some economic) uranium throughout younger rocks (such as Beverley, possible active very recently) So the fluid pathways and drivers are working well What about other traps? “uncomformity-related” just to give one possibility a name. So – first understand the processes.

Case study 2 – Athabasca and Cariewerloo

Multi-parameter lithostratigraphic logging Hyperspectral logging Magnetic depth to basement Geophysical Interpretation AEM survey Adobe 3D pdf Case study 2 – Athabasca and Cariewerloo

And numerous other projects That are not explicitly “Mineral Systems Approach” but nevertheless follow the same philosophy In fact, virtually all GSSA projects in some form have the MSP goal in mind, as well as mineral potential modeling and undiscovered resource endowment modeling but still some issues to resolve on data standards and delivery.

Issues and discussion Standard Mineral Systems approach: does not adequately address post-depositional modifications (maybe duration of events should be extended to multiple events) (Jaireth) this is related to the preservation issues Does not easily encompass co-existing deposit types in same mineral system(s) (Huston). e.g Gawler Craton IOCG, skarn, mesothermal gold, epithermal gold/silver and porphyries(?) Critical dataset collection should be prioritised by understanding critical processes and subsequently, targeting/mapable elements – not dumb precompetitive data collection to fill gaps. Only an understanding of the processes will determine scale-dependency and subsequent mapable criteria (even for Geological Survey’s precompetitive data collection)

Issues and discussion