CET Discovery Day. Mulga Rock Project The Ambassador, Emperor and Shogun discoveries. 24 February Xavier Moreau GM Geology & Exploration

Transcription

1 CET Discovery Day Mulga Rock Project The Ambassador, Emperor and Shogun discoveries 24 February 2015 Xavier Moreau GM Geology & Exploration

2 Mulga Rock Uranium Project Presentation Outline: 1. Context behind the discovery of the Mulga Rock Project 2. Commercial and regulatory aspects of the discovery 3. Project setting and key characteristics 1. Mineralisation 2. Size and ranking 3. Biogenic nature and other specific features of the project 4. Today s opportunity

3 Where is Mulga Rock?

4 Discovery history - Context in 1970 s A bit of recent Japanese history: Needed (and still does) to import most of its energy inputs Upheaval of the 1967 oil embargo and 1973 oil crisis with associated uncertainty of supply High population density and 1st world developed economy with associated high energy intensity 1972 Club of Rome Limits to Growth publication: U a rare commodity PNC (Power & Nuclear Company of Japan) mandate to look at uranium projects worldwide

5 Discovery history - Context in 1970 s Courtesy of I. Hore-Lacy, WNA

6 Today s context GDP / kwh correlation $70,000 $60,000 US $50,000 $40,000 $30,000 China ~ 2035 $20,000 Russia $10,000 China 2012 $0-5,000 10,000 15,000 20,000 25,000 30,000 Future growth of China Electric consumption per person of a population due to peak at just below 1.5 billion people Even with significant efficiency gains and shift from primary production, near doubling of 2012 power generation capacity required by 2035 Significant environmental and logistical constraints to increasing use of fossil fuels and in particular coal. Limits on capacity for additional hydropower

7 Discovery history - Context in 1970 s The target: Texas-style mineralisation Data available in the public domain on these deposits Super giants and high-grade of the Athabasca and low-cost Kazakh deposits (leachable in-situ) not yet found MESA, 48 Initially targeted roll-front mineralisation in Cretaceous paleodrainage coming off the Yilgarn, down-gradient from calcrete discoveries by WMC Area initially mapped by GSWA in 1972, not particularly inspiring given the combination of deep weathering profile, aeolian cover, lack of topography or breakaways and deep sedimentary cover: No SURFACE SIGNATURE On the ground exploration by PNC around Mulga Rock started in 1978 (20 wildcat holes along baseline, ~6-7km apart), on recommendations from Robertson Research

8 Discovery history - Context in late 1970 s What PNC faced Radiometrics Th, K, U as RGB

9 Initial Mineralisation model

10 Mineralisation model A few years later

11 PNC s exploration effort at Mulga Rock Holes Meters Drill hole #/yr Meters drilled/yr Year

12 PNC s legacy: Shogun trial pit ( ) 100 m ~35 m

13 PNC s legacy & CSIRO s involvement

14 PNC s legacy & CSIRO s involvement Significant research project completed in 1993 by CSIRO (under C. Butt and G. Douglas); it investigated : Organic matter characterisation and relationship with U mineralisation Geochemistry of Eocene sediments and underlying basement identified anomalous Ni, Co, Cu, V, REE Sequential extraction Groundwater characterisation Radiometric disequilibrium

15 Some historical impediments to bringing the MRP into production Technical Access to enough brackish water to enable IX or SX-based extraction + combustion processes Bulk mining methods to allow for larger volumes/greater annual revenues (forced to look at high-grading the deposits) Lack of regional infrastructure Understanding the inherent variability of host sequences and upfront beneficiation Regulatory Three mines policy ( ) No uranium mining W.A. State Labor policy in placed until late

16 What changed from the late 1980 s to the late 2000 s Understanding of: Regolith in Australia, in particular across arid landscapes Cenozoic geology of the southern Australian continental mass Discovery of Tropicana and satellite Au deposits

17 Discovery history - What we know today

18 Mulga Rock Project Today s ranking and global significance 18

19 Mulga Rock Project Host rocks 19

20 Mineralisation model and local stratigraphy 3 2 1: Patterson Fm. 2: Werrilup Fm. 3: Princes Royal Mb. 1 20

21 Short-scale grade variability (pxrf, 8 core) U (ppm) Zn (ppm) Fe (ppm) 20cm Ni (ppm) Co (ppm) Cu (ppm) 21

22 Mulga Rock Project Uranium mineralisation (data courtesy of S. Cumberland) 22

23 Mulga Rock Project Mineralogy Mineralised Lignite Organic+ sand+ Clay matrix Uranium Organic clasts 23

24 Mulga Rock Project Some specific aspects Biogenic mineralisation and mineralogy Lignite composite Sandstone composite 24

25 Mulga Rock Project Bio- mineralogy U speciation (data courtesy of S. Cumberland) 25

26 Weathering profile at Mulga Rock (ASD data) HQD 1,725nm 26

27 Mulga Rock Project Mineralising process and metal mobility Lowering of water table (neotectonics) oxidised sediments rich in sulphides and organic matter Dramatically enhanced mobility of metals on colloids Metals immobilised via microbial activity in OM-rich sequences downstream 27

28 Mulga Rock Project The road forward Technical Good understanding of weathering profile and material key to mine planning and design In-pit beneficiation to produce a more constant material to the plant means smaller footprint and lower capex, and likely lower acid consumption Acid leach replicates natural process, with natural buffering in paleochannel ground waters and host sediments Optimise existing regional infrastructure Regulatory Get approvals in place to minimise political risks to the project 28

29 Thank you for your attention 29

30 Mulga Rock Project Biogenic mineralisation Deposition of 50% of uranium from solution by reductive precipitation in different geological environments Mulga Rock 1 Time (ka) Temperature ( C) 30