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2010 the Annual Report for the Paleoproterozoic Mineralization Research Group

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2010 the Annual Report for the Paleoproterozoic Mineralization Research Group PPM Annual Report 2010 The Annual Report for the Paleoproterozoic Mineralization Research Group DEpartmENT OF GEOLOGY UNIVERSITY OF JOHANNESBURG The Annual Report of the Paleoproterozoic Mineralization Research (PPM) Group, compiled and edited by HM Rajesh and Nic Beukes. Layout and design by HM Rajesh and the UJ Graphic Studio. Special thanks/Acknowledgements We wish to extend a special word of thanks to all of our corporate and governmental financial supporters (in alphabetical order): African Rainbow Minerals Anglo American Anglo Coal Anglo Gold Ashanti Anglo Platinum Anglo Research Assmang Assore Coaltech Department of Science and Technology (DST) Lonmin National Research Foundation (NRF) Nkomati Joint Venture Rand Uranium (Gold One) Salt River Resources Ltd Please direct all enquiries and applications for research to: Prof. Nic Beukes or Prof. Fanus Viljoen PPM, Department of Geology University of Johannesburg Auckland Park Kingsway Campus PO Box 524, Auckland Park 2006 Johannesburg, South Africa E-mail: [email protected] or [email protected] Tel: +27 (0) 11 559 4712/4710/4711 Fax: +27 (0) 11 559 4702 http://www.uj.ac.za/geology Cover photo: View of the Bokkeveld (in foreground) and Witteberg strata of the Cape Supergroup at Gamkapoort Dam, Western Cape Province INTRODUCTION The PPM Research Group, formed in 1997 as an informal research group in the Department of Geology, has for the past four years been officially recognized by Management of the University of Johannesburg as one of the Research Centres of Excellence at the University. This meant that PPM received an annual research grant from the University Research Committee to strengthen the group especially with respect to funding salaries of support staff and providing additional bursary support to postgraduates and postdoctoral associates. A review of the research centres took place during 2010 and PPM was in the fortunate position to be awarded support funding for another three-years from 2011 to 2013, after which outputs shall again be reviewed. As part of the additional support from UJ we were able to appoint several new postdoctoral fellows in PPM. The funds also made provision for appointment of Profs Jan Kramers and Nic Beukes (who officially retired at end of 2010) on contract basis for another three years. Axel Hoffman joined the Department of Geology and PPM during August 2010. With this appointment the PPM Research Group further strengthened the research niche into the field of early Precambrian environments, especially origin of early life. Geometallurgy figured prominently in the research topics initiated by new students. New research projects were launched on the characterization of strategic minerals – PGE- and REE-bearing minerals. Prof. Nic Beukes again received an Al rating from NRF for another five year cycle that started in January 2010. During 2010, research focused in five main areas, namely geometallurgy-kimberlite research, metalliferous mineral deposits, paleomagnetism-provenance studies, early Precambrian environments and coal geology (see diagram below). In addition Prof Bruce Cairncross continued work on geoheritage research. PPM Research Group (2010) Staff and Students Leaders of the research group Prof. Nic Beukes, Prof. Fanus Viljoen Staff Members Prof. Bruce Cairncross, Dr. Michiel de Kock, Mr. Michael de Villiers, Prof. Jens Gutzmer Prof. Axel Hoffmann, Prof. Jan Kramers, Mr. Mike Knoper, Dr. Hassina Mouri, Prof. HM Rajesh, Mr. Bertus Smith, Dr. Herman van Niekerk Geometallurgy, Metalliferous Paleomagnetism, Kimberlite Research Mineral Deposits Provenance Studies Team Members Team Members Team Members Ms. A Crossingham Mr. B Chisonga Mr. R da Silva Ms. G Mishra Mr. F Kruger Ms. D Dreyer Ms. S Mkhatshwa Mr. T Mabundza Mr. P Fourie Ms. L Mngoma Mr. B Nel Ms. M Peche Dr. C McClung Mr. K Osburn Ms. C Vorster Mr. D Pretorius Mr. JC Beyeme-Zogo Mr. H Wabo Dr. B Richards Mr. D Rose Mr. F van der Merwe Coal Geology Early Precambrian Technical Support Environments Staff Team Members Team Members Mr. M Chakuparira Dr. H Tsikos (Rhodes) Mr. GA Belyanin Mrs. D Khoza Mr. P Meyer Mr. A Gumsley Mr. L Mangwane Mr. B van der Walt Mr. B Guy Mr. M Watts 1 PPM group members in the meeting room of the Geology Department RESEARCH PROGRESS AND HIGHLIGHTS Growth in geometallurgical research at the University of Johannesburg As the world demand for metals the mineralogical and textural associated silicate, oxide and sulphide increases, the focus changes to lower- characteristics of ore bodies, ores, minerals, in relation to metallurgical grade or problematic deposits that concentrates and successor products issues during the recovery of platinum- would not have been mined in the past. in resource types relevant to the South group elements. Research is also Without a thorough understanding African minerals industry. Research focussed on geometallurgical aspects of of the mineralogical constraints (i.e. is focused on the characterisation of gold, diamond, nickel, the base metals variations in mineral compositions, size, platinum-group element mineralisation (copper-lead-zinc), coal and lime, with morphology, mineralogical associations, within the Merensky Reef and the a view on the optimisation of treatment impact of grind size on liberation and Plat Reef of the Bushveld complex, plants and optimised metal recovery. the reason for deportment of minerals utilising mineralogical and geochemical During 2010 papers were presented by in certain streams) interpretation techniques such as X-ray diffraction Geometallurgy students and staff at the of metallurgical test work could be analysis, scanning electron microscope- Geological Society of America Meeting flawed. This highlights the necessity based automated mineralogy, and in Denver, Colorado, the Society of for conducting in-depth mineralogical, electron microprobe analysis. Research Economic Geologists Conference petrographical and mineral chemical into automated mineralogy as applied in Keystone, USA, the International investigations in order to obtain a better to the characterisation of ores and ore Mineralogical Association Conference understanding of the metallurgical bodies is conducted on a ‘state-of-the- in Budapest, Hungary, and the Process behaviour imparted by these ores. art’ FEI 600F Mineral Liberation Analyser Mineralogy 2010 Conference in Cape The primary thrust of the geometallurgy at UJ. An example is the determination Town. Five MSc projects, six PhD group is to develop and apply of the mineralogy of various ores of the projects, and one post-doctoral project geometallurgical methods to quantify platinum-group elements, along with is currently in progress. Some of the geometallurgy group members at the IMA meeting in Budapest, Hungary 2 Metalliferous mineral deposits Research on the iron ore potential of During 2010 we took part in ores deposits. The third workshop, co- the Asbestos Hills region in Griqualand presentation of three workshops on organized by the Universities of Brasilia West continued during 2010. The main banded iron formation and associated and the Federal University of Ceara, was aim of this project is to establish the iron ores. The first was at PDAC held in Fortaleza, Brazil towards the end high-grade iron ore potential of the in Toronto, Canada during March of November 2010. The main presenters region outside of the area of the known 2010 where Jens Gutzmer, Joydip at the workshop were Michael Bau from high-grade BIF-hosted hematite iron Mukhopadhyay and Nic Beukes Jacobs University in Germany and Nic ore deposits of the Sishen-type on the presented talks on the iron ores of Beukes. Michael Bau was responsible Maremane Dome. In addition research southern Africa and India as well as for presenting geochemical aspects of is also undertaken on low-grade iron models for the origin of high-grade BIF- iron formations while Nic presented ores and banded iron formation of hosted iron ores in general worldwide. two afternoon lecture series on the the region to establish their potential The second workshop took place at sedimentology of iron formations, for beneficiation to saleable iron the University of Minnesota in Duluth high-grade iron ore deposits and ore products. Another project aims during October 2010. It was the Fourth the classification, nature, origin and at characterizing high-grade small Professional Workshop organized by paleoenvironmental significance of magnetite ore bodies and associated Precambrian Research Center of the Precambrian manganese deposits. The supergene-modified hematite ore University of Minnesoata in Duluth and workshop was followed by a weeklong bodies in the Mesoproterozoic Gams focused on BIF and associated ore field trip to Archean and Proterozoic Formation of the Bushmanland deposits. As one of the invited lecturers iron formations and associated rocks to succession in the Namaqua Nic Beukes presented a seminar on BIF- the southeast of Fortaleza. Metamorphic Belt. hosted manganese and high-grade iron Nic Beukes with students and staff of the Universities of Brasilia and Ceara that attended a field excursion to iron formations southeast of Fortaleza in Brazil. Co-presenter of the workshop, Michael Bau, is in the back row second from right Delegates of the Duluth BIF Workshop workshop looking at what appears to be a channel-fill of granular iron formation in banded lutitic iron formation at one of the iron ore mines in the Mesabi Range, Minnesota 3 Developments in Geoheritage Recent developments in geoheritage out that rare geological specimens,
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