Stewart R. Wallace — 1919–2009 - Society of Economic Geologists

More documents

Recommendations

Info

EXPLORATION REVIEWS 42 SEG NEWSLETTER No 78 JULY 2009 ... from 41 Exploration Reviews (Continued) SOUTH AUSTRALIA Oz Minerals’ Prominent Hill IOCG mine commenced production in Febru - ary, with first copper-gold concentrates being railed out to Darwin for export. Resources continue to expand at the deposit, with the most recent drilling campaign increasing the “Western Copper” deposit by 32% to 245 kt of contained copper. Inferred Resources at the Western Copper deposit now stand at 14.5Mt @ 1.7% Cu, 0.28g/t Au and 3.7 g/t Ag. Total resources at Prominent Hill stand at 283.2 Mt @ 0.9% Cu, 0.8 g/t Au and 2.5 g/t Ag (2.5 Mt Cu, 7.4 Moz Au, and 22.6 Moz Ag). Oz Minerals plans to produce 85 to 100 kt of copper and 60 to 70 koz of gold in concentrates in 2009. The deposit remains open to the east, west, and at depth. An interesting aside to the success of Prominent Hill (discovered by Minotaur Resources in 2001) is the fact that it was perceived to be “the jewel in the crown” in the Oz Minerals stable (which included the Rosebery, Century, and Golden Grove base metal mines in Australia and the Martabe gold project in Indonesia) during the recent takeover negotiations with the China Minmetals Group. The Foreign Investment Review Board of thefederal government approved the takeover but ruled that the Prominent Hill mine should be excluded from the takeover on national security grounds as it was located within the vast Woomera rocket rang; hence, Prominent Hill remains with Oz Minerals, while most of the other assets are now owned by Minmetals. BHP Billiton is seeking the approval of the Australian, South Australian, and Northern Territory governments for a significant expansion of its existing mining and processing operation at Olympic Dam in northern South Australia. The Olympic Dam mine produces copper, uranium, gold, and silver from a massive IOCG deposit. It is the world’s fourth largest copper and gold deposit, and the largest uranium deposit. It also contains significant quantities of silver. The proposed expansion would be a progressive development, requiring construction activity over a period of 11 years. The company plans for the new open pit mine to operate simultaneously with the existing underground operations— and remember that the deposit is buried under 300 m of younger cover rocks! Once the new expansion is completed, mining rates will increase to 72 Mtpa, compared to the current mining rate of 12 Mtpa from the underground operations. This will produce 2.4 Mt of copper concentrate each year and 750 kt of refined copper, along with 19 kt of uranium oxide, 800 koz of gold bullion and 2.9 Moz of silver bullion. WESTERN AUSTRALIA In recent years, companies have explored beneath the oxide gold deposits in the WA deserts for primary gold deposits, and at its DeGrussa prospect in the Meekatharra district, Sandfire Resources has hit the jackpot. A program of 30 reverse circulation drill holes was completed to teat for depth extensions to a 220-m-long zone of previously discovered oxide gold mineralization. The holes intersected an extensive zone of Cu-Au-Ag mineralization (with Zn and Pd credits), with better intersections including 47m @ 5.3% Cu, 26 m @ 3.2% Cu, 75 m @ 2.4% Cu, and 22 m @ 4.9% Cu. Resource definition drilling is underway, as are airborne, ground, and downhole EM surveys as the mineralization is strongly conductive. In order to attract exploration to the more remote regions of Australia, the state and federal agencies are systematically collecting regional geologic, geochemical, and geophysical datasets, and releasing these to explorers at minimal cost. One winner from this wise investment has been Meteoric Resources. The company has secured priority right of application to a regional 10 ´ 8 km gold-in-soil anomaly which was identified by a helicopter-supported regional geochemical sampling program carried out by Geological Survey of WA following field work by Geoscience Australia which highlighted the coppergold and gold potential of the Mt Webb area in the western part of the Arunta Complex. The Arunta Complex extends across the WA/NT border and comprises an extensive sequence of Proterozoic metamorphic rocks intruded by granites. The main anomaly is based on regolith samples taken on a grid cell of 5 × 2.5 km equating to one sample per 12.5 km2 . This wide-spaced sampling has defined a coherent gold anomaly with gold-in-soil values ranging from 10 to 20 times background (1 ppb Au) and one lag sample (surficial rock float) containing 0.4g/t Au. The gold anomaly is supported by anomalies in a range of other elements. Integra Mining has reported further high-grade intersections from diamond drilling at its Salt Creek gold deposit, forming part of its Randalls gold project located 60 km east of Kalgoorlie, adjoining the Trans Australian Railway. Recent intersections have included 40.5 m @ 6.48 g/t Au and 15.5 m @ 4.51 g/t Au. The feasibility study for the Randalls project is expected to be completed midyear, based on a resource of 1.8 M oz Au at a grade of 2.8 g/t Au. A step-out drill hole at Mincor Resources’ Mariners nickel mine assayed 35 m @ 7.0% Ni (true width 6.4 m) located 180 m beyond the currently known limits of mineralization and suggesting the potential for new ore shoots. NORTHERN TERRITORY Emmerson Resources’ exploration efforts in the Tennant Creek goldfield have been boosted by the entry of Ivanhoe Australia as a shareholder in the company and also as a joint-venture partner in all of Emmerson’s tenements in the district. Tennant Creek is one of the richest and largest Proterozoic goldfields in Australia with historical production of more than 5.5 Moz of highgrade gold and approximately 488 kt of copper. NEW ZEALAND Perth-based Western Media Holdings launched www.nzresources.com, which features news about mineral and energy resources in New Zealand. They also published The Mineral Resources of New Zealand 2009, a CD-ROM containing information on mines, prospects and companies. It is available from them, or in the New Zealand Minerals Information Pack offered by Crown Minerals, see www.crownminerals.govt. nz/cms/minerals/publications/publica tions#NZinfopack. In the Hauraki goldfield, Newmont has continued drilling near-mine epithermal gold prospects adjoining their Waihi gold mine and have also initiated reconnaissance diamond drilling on Glass Earth Gold permits approximately 15 km to the north of Waihi. Encouraged by the recent high gold price, Newmont is investigating both an eastern extension to the Martha open pit and underground mining of the Gladstone zone from a drive extension from the Favona underground mine. At Oceana Gold’s Macraes orogenic gold mine in Otago, 34 drill holes were completed to test the northeastern extension of the Coronation deposit,
JULY 2009 No 78 SEG NEWSLETTER 43 ~5 km north of the current mining area. Significant intercepts (with grades >1 g/t Au over 1–5 m) exist within both the hanging-wall shear zone itself and a semi-concordant lode that occurs about 10 m below. Both appear to be shallow, north-plunging ore shoots. At the Macreas mine, exploration drilling from underground is in progress to further define the Panel 2 Deeps mineralised zone, with mineralized intercepts ranging from 2 to 27 m in thickness. Average grades across these intervals range up to 7.2 g/t Au using a 10 g/t Au top cut. Development work has started on an exploration drive above the main mineralization at the fringes of Panel 2 to provide an area from which underground exploration and resource definition drilling can be efficiently completed. CANADA Contributing Correspondent: Ryan Weston P.Geo., Consulting Geologist weston.rj@gmail.com Canadian Correspondent: Ross Sherlock, Gold Fields Canada QUEBEC For the second year in a row, Quebec has once again topped the ranks as the world’s number one jurisdiction for mining and mineral exploration investment, according to the Fraser Institute’s 2008-2009 survey of mining companies. This is, no doubt, due largely to the favorable tax incentives mining and exploration companies enjoy while ex - ploring in Quebec, including significant tax credits for eligible exploration ex - penses (up to 50% government rebates), and the ability to raise money via superflow through share issuance (whereby both provincial and federal tax credits apply). Substantial capital raisings by some of Quebec’s most active junior players (e.g., Osisko Mining $403 M in February 2009; Aurizon Mines $50M in April 2009) during the height of the current credit crisis supports this view. World-class geologic potential, highquality government survey reporting, up-to-date tenure information available over the internet and the recent switch (2000) to paper-based map staking have all contributed to Quebec’s thriving exploration industry. Exploration expenditures in 2008 topped out at $450M (down from $476M in 2007), the bulk of which was spent by junior mining companies. In 2007– 2008, exploration largely focused on gold (47.4% of exploration expenditures) and to a lesser extent base metals (24.8%), uranium (14.9%), ferrous metals (6.1%), and diamonds (5.6%). Active exploration claims presently cover 120,000 km 2 , or roughly 7.8% of the province, a record high. In the gold sector, several exploration companies have been busy defining high-grade resources, and in the case of a lucky few, bringing into production quality gold mines in time to enjoy the riches of $900+/oz gold. Within the Val d’Or camp of the famous Abitibi greenstone belt, notable projects moving forward include Osisko’s Canadian Malarctic deposit with proven and probable mineral reserves of 6.3 Moz at 1.1 g/t Au. A positive feasibility study released in Nov/08 estimates annual production of 0.6 Moz gold over a 10-year mine life with cash costs of $319/oz. Capital expenditures are expected to total $789M. The deposit is interpreted to be an Archean-age gold porphyry, and as such represents a new target in the Abitibi subprovince, where most gold deposits occur as structurally controlled mesothermal veins. Aurizon Mines’ Casa Berardi gold mine, located 130 km northwest of Val d’Or, restarted in 2006 and has produced 375,000 oz Au since. With reserves of 0.96 Moz @ 7.8 g/t Au, the mine is projected to produce 150,000 oz Au in 2009 at cash costs of $390/oz. Another junior breaking through to producer, Alexis Minerals began producing at its Lac Herbin mine in Sept/08. The mine, with a global resource of 280,000oz at 6 to 8 g/t Au is targeting 40,000 oz production in 2009 at cash costs of $545/oz. Alexis is also developing its Lac Pelletier deposit (216,405 oz at 5.4g/t Au) and continues exploration at its West Ansil polymetallic VMS discovery in the Noranda camp. In Aug/08 Agnico Eagle’s Goldex mine began commercial production with 36,000 oz Au produced in 2008 at cash costs of $318/oz. With proven and probable reserves of 1.6 Moz at 2.1 g/t Au, the mine is slated to produce 160 koz Au/year to 2017. At its LaRonde Aurich VMS mine, Agnico Eagle is busy constructing access to the LaRonde Extension, which will add 19.9 Mt at 6 g/t Au for a further 3.8 Moz, extending the mine life to 2021. IAMGOLD completed a positive preliminary economic assessment of its Westwood deposit located 40km east of Noranda. The deposit hosts 3.2 Moz at 8.6 g/t Au. The study forecasts 200 koz Au production annually for the first 13 years at cash costs of $290/oz. The company is aiming for production to begin by 2013. A new and exciting gold district is emerging in the James Bay area of western Quebec as a result of the discovery of the Eleanore deposit in 2004 by Virginia Gold Mines (now Virginia Mines). In 2005 Goldcorp purchased Eleanore for $420M and by Dec/08 the Roberto zone of the project contained a measured, indicated, and inferred resource of 5.3 Moz at 11.4 g/t Au. The project is currently undergoing in-house feasibility studies. The project straddles the contact between the Opinaca metasedimentary subprovince and the Archean La Grande volcanoplutonic subprovince. Supracrustal rocks of the region are intruded by synvolcanic, syntectonic, and post to late-tectonic tonalite-trondhjemite-granodiorite suites (TTG). Eastmain Resources’ Eau Claire deposit, located 40 km southeast of Eleanore and within the same geologic belt, contains an indicated and inferred resource of approximately 1 Moz within high-grade (7–10 g/t Au) quartz-tourmaline veins. In Quebec’s Grenville province, Laurentian Goldfields has staked 1,200 km2 in pursuit of a Tropicanastyle gold target. Until recently, the Grenville province has experienced limited past exploration; however, the geologic setting and age of the Grenville province and adjacent Archean Superior province is a close analogy to Western Australia’s Albany-Fraser Proterozoic belt which hosts AngloGold Ashanti’s Tropicana deposit (reported to host more than 5 Moz Au), adjacent to the Archean Yilgarn craton. Laurentian’s target model is being supported by a recently announced $5.8M investment over three years from major AngloGold Ashanti. Despite depressed metal prices, base metal exploration continues in Quebec’s greenstone belts. In July 2008, Xstrata Zinc inaugurated its Perseverance polymetallic VMS mine located in the historic Matagami camp. The deposit contains 5 Mt of 13.6% Zn, 1% Cu, 0.3g/t Au and 30g/t Ag and has an expected mine life of 5.5 years. First Metals began production at its Fabie Bay copper VMS mine near Rouyn-Noranda in Mar 2008. The mine has reserves of 0.6 Mt @ 2.8% Cu. Virginia Mines and Breakwater Resources recently released a resource on their jointly owned Coulon VMS project in north-central Quebec of 13.7 Mt at 1.3% Cu, 3.8% Zn, 35 g/t Ag and 0.2 g/t Au. In nickel exploration, Goldbrook Ventures and partner Jilin Jien Nickel Industry have discovered a to page new deposit at their 44 ... EXPLORATION REVIEWS
Page 1 and 2: Advancing Science and Discovery SEG
Page 3 and 4: JULY 2009 No 78 SEG NEWSLETTER 3 SE
Page 5 and 6: JULY 2009 No 78 SEG NEWSLETTER 5 FR
Page 7 and 8: JULY 2009 No 78 SEG NEWSLETTER 7 PR
Page 9 and 10: JULY 2009 No 78 SEG NEWSLETTER 9 co
Page 11 and 12: JULY 2009 No 78 SEG NEWSLETTER 11 S
Page 13 and 14: JULY 2009 No 78 SEG NEWSLETTER 13 D
Page 15 and 16: JULY 2009 No 78 SEG NEWSLETTER 15 F
Page 17 and 18: JULY 2009 No 78 SEG NEWSLETTER 17 m
Page 21 and 22: JULY 2009 No 78 SEG NEWSLETTER 21 M
Page 27 and 28: JULY 2009 No 78 SEG NEWSLETTER 27 6
Page 29 and 30: JULY 2009 No 78 SEG NEWSLETTER 29 T
Page 33 and 34: JULY 2009 No 78 SEG NEWSLETTER 33 I
Page 35 and 36: JULY 2009 No 78 SEG NEWSLETTER 35 A
Page 37 and 38: JULY 2009 No 78 SEG NEWSLETTER 37 q
Page 39 and 40: JULY 2009 No 78 SEG NEWSLETTER 39 r
Page 41: JULY 2009 No 78 SEG NEWSLETTER 41 i
Page 45 and 46: JULY 2009 No 78 SEG NEWSLETTER 45 P
Page 47 and 48: JULY 2009 No 78 SEG NEWSLETTER 47 s
Page 49 and 50: JULY 2009 No 78 SEG NEWSLETTER 49 o
Page 51 and 52: JULY 2009 No 78 SEG NEWSLETTER 51 W
Page 53 and 54: JULY 2009 No 78 SEG NEWSLETTER 53 U
Page 55 and 56: JULY 2009 No 78 SEG NEWSLETTER 55 M
Page 57 and 58: JULY 2009 No 78 SEG NEWSLETTER 57 T
Page 59 and 60: JULY 2009 No 78 SEG NEWSLETTER 59 E
Page 63 and 64: THINK AHEAD BHP Billiton is all abo

Stewart R. Wallace — 1919–2009 - Society of Economic Geologists

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?