About the Project
This project is one of a number that are in competition for funding from the NERC GW4+ DTP. The GW4+ DTP consists of the Great Western Four alliance of the University of Bath, University of Bristol, Cardiff University and the University of Exeter plus six Research Organisation partners. The partnership aims to provide a broad training in earth and environmental sciences, designed to train tomorrow’s leaders in earth and environmental science. For further details about the programme, please see http://nercgw4plus.ac.uk/.
Background
Copper is an increasingly vital commodity as the global economy becomes more dependent on electricity. The world class copper deposit at of Mount Isa has produced over 200 million tonnes, but controversy over its formation hinders exploration for new resources at the mine and regionally. Proponents of a syngenetic origin point to the proximity of the copper ore bodies to the world class Mount Isa Pb-Zn deposit, widely accepted as related to Proterozoic basin formation at around 1640 Ma.
In contrast, a hydrothermal origin 100 Ma later has been suggested from isotopic evidence. This project will combine new mapping with over 70 years of surface and underground data, and apply recent developments in structural geology, geometrical and mechanical modelling, and geochronology. Integration of data from micron to km scales will radically advance understanding of the genesis and the geometry of the copper ore bodies, with direct exploration benefits..
Project aims and methods
The project aims to resolve the origin of the copper ore bodies at Mount Isa.
Three methods will be used:
- Detailed mapping and 3D modelling at m to km scales. New underground mapping will be combined with reinterpretation of mine geological and structural records to delineate ore bodies and structures. Alteration will be mapped from underground observations, new core logging and the drill hole database. Implicit modelling will define relationships of ore bodies to alteration, deformation and mineralisation.
- Paragenesis and Dating. Underground and core samples will be used to define the paragenesis in separate ore bodies, using advanced Scanning Electron Microscopy for mineral composition and whole thin section geochemical mapping on micron scales. Dating of fabric-defining minerals will constrain the timing of mineralization.
- Mechanical modelling on scales from cm to km. Mechanical modelling of continuous and discontinuous styles of deformation and their interaction will be carried out.
These methods will be combined with new insights from structural geology to test hypotheses about the role of foliation boudinage in localising the ore body, and the importance for mineralization of cyclic interactions between fracture and brecciation, and cleavage, folding and boudinage.
Candidate
The PhD candidate will have a strong structural geology background and be an enthusiastic mapper. You will be comfortable working underground and in the mine environment. Ability to work independently will be essential, as well as to interact closely with the mine personnel and to follow health and safety procedures.
CASE award
The CASE award is for the candidate to work with Mount Isa Mines in order to assist predictive exploration at the mine and regional scale. You will be based at Mount Isa for a total of 8 months in two campaigns, as part of the underground and exploration teams. Weekly reporting to Mount Isa Mines personnel when on site will ensure that Mount Isa Mines benefits immediately from the research, which will have direct exploration implications.
Training
You will receive advanced training in structural and economic geology at Cardiff University and Mount Isa. Structural geology training will include theory and practical skills (mapping, core logging, 3D and mechanical modelling). Economic geology training will include electron beam analysis for paragenetic studies, and geochronology at Adelaide University.
We provides a comprehensive doctoral skills programme via workshops, online materials and events, including topics such as science communication, programming and statistical packages, and career planning support. You will also access to GW4+ training courses. The supervisory team combines academic strength with a wealth of industry experience.
References
• . Arslan, A., Passchier, C.W., Koehn, D., 2008. Foliation boudinage. Journal of Structural. Geology 30, 291–309.
• Davis, T P, 2004. Mine-scale structural controls on the Mount Isa Zn-Pb-Ag and Cu orebodies, Economic Geology and the Bulletin of the Society of Economic Geologists, 99:543–559.
• Heinrich, C A, Andrew, A S, Wilkins, R W T and Patterson, D J, 1989. A fluid inclusion and stable isotope study of synmetamorphic copper ore formation at Mount Isa, Australia, Economic Geology and the Bulletin of the Society of Economic Geologists, 84:529–550.
• Heinrich, C A and Cousens, D R, 1989. Semi-quantitative electron microprobe analysis of fluid inclusion salts from the Mount Isa copper deposit (Queensland, Australia), Geochimica et Cosmochimica Acta, 53:21–28.
• Matthai, S.K., Heinrich, C.A., Driesner, T., 2004. Is the Mount Isa copper deposit the product of forced brine convection in the footwall of a major reverse fault? Geology 32, 357–360.
• Mclellan, J.G., Sullivan, R.O., Miller, B., Taylor, D., 2014. Geomechanical Modelling of the Mount Isa Copper Deposit – Predicting Mineralisation, in: Ninth International Mining Geology Conference. Adelaide, pp. 18–20.
• Perkins, W G, 1984. Mount Isa silica dolomite and copper orebodies: the result of a syntectonic hydrothermal alteration system, Economic Geology, 79:601–637.
• Perkins, W G, 1990. Mount Isa copper orebodies, in Geology of the Mineral Deposits of Australia and Papua New Guinea, pp 935–941 (The Australasian Institute of Mining and Metallurgy: Melbourne).
• Perkins, W G, 1997. Mount Isa lead-zinc orebodies; replacement lodes in a zoned syndeformational copper-lead-zinc system?, Ore Geology Reviews, 12:61–111.
• Swager, C P, 1985. Syndeformational carbonate-replacement model for the copper mineralization at Mount Isa, Northwest Queensland; a microstructural study, Economic Geology and the Bulletin of the Society of Economic Geologists, 80:107–125.
Continue with Facebook
