oreNewsletter of CODES, the ARC Centresolutions of Excellence in Ore Deposits at the University of Tasmania Winter 2009 / No. 25 New approach to uranium-gold systems team led by Dr David The project builds upon expertise in in these deposits, and the conditions under Selley from CODES, and sediment-hosted base-metal ores (Cu- which they attain ore grade concentrations. Co and Pb-Zn) that has been developed Consideration of these polymetallic Prof. Murray Hitzman A through two decades of research on some deposits as a spectrum between end- from the Colorado School of of the world’s most richly endowed basins, continued page 2 » Mines (CSM) node, is proposing including McArthur Basin in northern a research project to develop Australia and the Katangan Basin in central Temple Mountain, Utah – one of the sites Africa. The project also includes intellectual selected for deposit case studies. The mountain and test a holistic exploration is famous for its polymetallic urano-organic ores, capital developed through recent model for the formation and which include fracture-controlled varieties within research of world-class sediment-hosted and at the margins of a transgressive collapse location of polymetallic U-Au- Au provinces - in particular, concepts of breccia, and greater stratabound concentrations PGM-Ni-REE-Mo-Co ores. organically-mediated metal concentration. within sandstones of the Moss Back Member. Bleaching within the collapse (reduction of iron) In developing the models, emphasis will and abundant petroliferous organic matter within be placed on understanding the significance peripheral sandstones record infiltration of mobile of precious metal and base metal enrichment hydrocarbons. In this issue: SEG students in Indonesia 3 Grim trip 10 Portable analyser analysed 6 Tungsten, fire and ice 12 South American short course 8 Another Fox in Tasmania 14 « continued from page 1 ore location, and examine the potential for in terms of timing, structural control, members will provide important insight to systematic basin-scale metal zonation. alteration and geochemistry? metal sourcing, transport, and ultimately • What are the similarities and differences the distribution of ore-grade metal The search for answers in terms of metal sources and the types of accumulations in sedimentary basins. Answers will be sought to several key fluids involved in the transportation and questions regarding the U metallogeny of mineralisation? The project will include sedimentary basins, including: 3 modules: • What are the factors that control the The team • Metal sources and transport – a series location of polymetallic U deposits, their The project is being facilitated and funded of studies examining the relative roles size, grade and potential for significant through AMIRA International. In addition to of organic-bearing strata and Fe-oxide- credits of Au, PGM, Ni, REE, Mo, and Co? the team leaders – Dr Dave Selley and Prof. bearing ‘red bed’ strata as metal reservoirs, • Is there a spectrum of polymetallic U Murray Hitzman – the other team members and the conditions under which various deposits related to different stages of basin are: CODES personnel: Dr Stuart Bull, Dr metals can be released into solution. The evolution – from early diagenesis through Garry Davidson, Assoc. Prof. Jeff Foster, Prof. studies aim to reveal criteria that determine orogenesis? And can different deposits be Ross Large, Dr Karin Orth, Dr Robert Scott, a basin’s fertility from the perspectives of found in the same basin? plus Dr Poul Emsbo from USGS, and Dr metal source and transport. • Do the various components of Robert Duncan, Prof. Thomas Monecke and • Deposit case studies – comparative polymetallic U deposits share a common Prof. Sam Romberger, all from CSM. studies of deposits from central Africa source? (Shinkolobwe), northern Australia • Is it possible to relate variations in Sponsorship (Coronation Hill, Rum Jungle), USA (Temple metal ratios and absolute concentrations It is anticipated that sponsorship will be Mountain), and South America (Serra to variations in metal source type? an attractive proposition for companies Pelada). The deposits and host basins • Is the zonation of U, Au, PGM, Ni, Mo, exploring for, and developing, uranium, gold, will be selected to include a spectrum Co, and Cu apparent in some basins (e.g. PGMs and related base metal deposits. There of stratal types and positions, association Katangan Basin) unique? will be two types of sponsorship, aimed at with (former) organic matter, and diversity • What is the potential for significant base major and junior levels of participation. of metal associations from U-dominated to metal and precious metal mineralisation Au-PGM-dominated end-members. in provinces known mainly for their U For further information and • Basin architecture – structural, endowment (and vice versa in the case of sponsorship opportunities contact: lithostratigraphic, and hydrodynamic Cu-rich basins)? David Selley. Tel: + 61 3 6226 2481 studies examining the positions of various • How do polymetallic U deposits in Email: [email protected] ore types within their respective host basins. different geologic settings compare with Murray Hitzman. Tel: +1 303 384 2127 The studies develop predictive models for classic unconformity-related U deposits Email: [email protected] Teaching in the City of Gold Ross Large lecturing in Johannesburg, South Africa. During March, Ross and Stuart Bull presented a five-day workshop to 20 Vale geologists entitled Ore forming processes in sedimentary basins. Johannesburg is often referred to in South Africa as Egoli, which is a Zulu word meaning ‘city of gold’. The name is derived from the city’s rich gold mining history. 2 ore solutions Winter 2009 / No. 25 Highs, lows and eruptions All part of the day for SEG students in Indonesia Left: A bird’s eye view of the processing plant at Grasberg taken from the cable car transporting the SEG team. Below: Bronto Sutopo and Fiona Best on Krakatau. he SEG student chapter has The field trip, entitled ‘The Mineralisation completed a hectic, but and Volcanism of Indonesia’, enabled the participants to observe economic highly successful, 11-day T epithermal and porphyry deposits, study field excursion to Indonesia the lavas of active volcanoes, and gain an still visible. On day two, the group endured a that included visits to five overall understanding of the geodynamical rather wet and bumpy boat ride to Krakatau Indonesian islands, three mine evolution of the country. Six industry in the Sunda Strait, where they observed sites and two active volcanoes. representatives and eight students from several generations of lava flows at the base CODES attended the trip, with participants of the volcano, before scrambling through Highlights of the trip were a originating from Australia, and as far afield the steam to see the craters at an elevation tour of the legendary Krakatau as the UK, Canada, Columbia, Indonesia, of approximately 300 m. On the final day on volcano (which in 1883 was Italy, Japan, Peru, Russia and Thailand. Java, the group visited Pongkor gold mine the site of one of the world’s The beginning of the tour was timed where they were taken 500 m underground to coincide with a conference in Jakarta, to observe the mineralised quartz-adularia- most cataclysmic eruptions), organised by the Indonesian Society of sericite veins. a journey underground at Economic Geologists (MGEI), entitled The next two days were spent in the Pongkor and an ascent to the ‘Sumatra Metallurgy at a Glance’. With province of Papua where they learned heights of the world-famous presentations with titles such as ‘1883 about the famous Grasberg porphyry Au- open pit mine at Grasberg. Krakatau Eruption’ and ‘The Status of Gold Cu deposit. The group attended lectures Resources and Exploration in Indonesia’ the on the regional geology and characteristics conference provided the perfect starter to of the Grasberg deposit, and then made whet the appetite for what was to follow. observations of the porphyry ore bodies, The official start to the field trip sulphide-rich skarns and country rocks in commenced with a visit to Carita, West Java, core. They then travelled to an elevation of where the participants were captivated by >4000 m for a geological tour of the vast a large collection of Pliocene silicified trees open-pit operations. that were so well preserved that, in places, Next stop on the demanding but the cell structure of the original wood was eventful schedule was the Batu Hijau gold- ore solutions Winter 2009 / No. 25 3 Highs, lows and eruptions « continued from page 3 rich porphyry copper deposit on the remote learned about its history and evolution, Congratulations to the main organisers, island of Sumbawa in the Lesser Sunda studied the active crater and observed the Fiona Best and Bronto Sutopo, on a highly Archipelago. During a two-day stay at Asia’s lava flows and ignimbrites at its base. rewarding and well-planned 11 days. second largest copper mine, the group was given a tour of the operations and briefed on the geology and mineralisation of the ore body. They were also afforded the opportunity to view core from the mineralised bodies and country rock. The final two days of an unforgettable journey were spent in Bali visiting the active Mount Batur volcano where the group Above: The sign says it all. Left: Dr Clara Wilkinson takes a photo of a petrified tree on the way to Pongkor. some of Tasmania’s finest Plans for symposium cool climate varietals. It is down to the gather pace serious business on days two and three with a Planning for the special symposium to mark full program of top local, CODES’ 20th anniversary is progressing national and international well. A number of prominent speakers have speakers, who will already confirmed their participation, and deliver presentations on many others are expected to finalise their a range of ore deposit involvement in the next few weeks.
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