Effectiveness of Transient Electromagnetics in Mineral Deposit Exploration: A Case Study of the Kerry Road Cu-zn-au Sulphide Deposit, Northwest Scotland
Abstract
It is well known that mineral deposits with surface showing have long been discovered and only ‘blind’ and deeply buried deposits are yet to be discovered. It is equally well known that the global economic growth is dependent upon non-renewable resources, particularly minerals, and will continue doing so for sometime to come. The global population is projected to grow by about 1.6 billion from 6.1 to 7.7 billion people by the year 2020, with most of this growth taking place in developing nations. The demand for minerals in developing nations will equally increase. Finding new deposits to satisfy this demand is therefore a challenge and requires not only the use of more effective exploration techniques but also combining a number of methods to increase the chances of discovery. This paper discusses the Transient Electromagnetics (TEM) method and its effectiveness in mineral exploration using the stratiform volcanogenic massive Cu-Zn-Au sulphide deposit at Kerry Road in northwest Scotland as a case study. This deposit is hosted in the Proterozoic Loch Maree Group (LMG) composed of metagreywackes and metabasalts. The ore occurs in a quartz-carbonate horizon composed of 15-20% pyrite, pyrrhotite plus chalcopyrite, sphalerite, marcasite and galena. Earlier geophysical studies and drilling of the deposit had detected mineralisation at a depth of about 9 m. Exploration with TEM detected the same mineralization at a depth of about 8 m with a dip of 88-90o thereby demonstrating the effectiveness of the technique.References
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2. Buseli, G., & O’Neill, B. (1977). SIROTEM: A new portable instrument for multichannel transient electromagnetic measurements. Bulletin of the Australian Society of Exploration Geophysicists, 8, 82–87.
3. Coats, J. S., Shaw, M. H., Rollin, K. E., & Fortey, N. J. (1997). Mineral exploration in Lewisian supracrustal and basic rocks of the Scottish Highlands and Islands. Retrieved from https://www.bgs.ac.uk/mineralsuk/exploration/potential/mrpsumm141-146.html.
4. Fokin, A. F. (1971). The method of transient processes in the search for sulphide deposits. Leningrad: Nedra, 242 pp.
5. Griffith, D. H., & King, R. F. (1988). Applied Geophysics for Geologists and Engineers – The Elements of Geophysical Prospecting. Oxford: Pergamon Press, 230 pp.
6. Jones, E. M., Rice, C. M., & Tweedie, J. R. (1987). Lower Proterozoic stratiform sulphide deposits in Loch Maree Group, Gairloch, northwest Scotland. Transactions of the Institution of Mining and Metallurgy (Section B: Applied Earth Sciences), 96, B129–B140.
7. Kamenetskii, F. M. (1976). Handbook of Applied Methods of Transient Processes in Ore Geophysics. Leningrad: Nedra, 127 pp.
8. Maher, M. J. (1992). Transient electromagnetic surveys in the Okiep District. Geophysics, 57, 736–745.
9. Meju, M. A. (1990). TEMOD: A desktop system for processing and modeling central and coincident loop data. Unpublished University of Leicester Geophysical Research Report 90/1.
10. Meju, M. A. (1992). Iterative most-square inversion: Application to magnetotelluric data. Geophysical Journal International, 108, 758–766.
11. Park, R. G. (1964). The structural history of the Lewisian rocks of Gairloch, Wester Ross, Scotland. Quarterly Journal of the Geological Society of London, 120, 397–433.
12. Peacock, J. D., & Michie, U. M. (1975). Superficial deposits of the Scottish Highlands and their influence on geochemical exploration. In Jones, H. J. (Ed.), Prospecting in Areas of Glaciated Terrain (pp. 40–52). London: IMM.
13. Sikazwe, O. N. (1992). An integrated geophysical study of the Kerry Road Cu-Zn-Au sulphide deposit, Gairloch, northwest Scotland. University of Leicester MSc Thesis, 89 pp.
14. Sutton, J., & Watson, J. V. (1951). The pre-Torridonian metamorphic history of the Loch Torridon and Scourie areas in the northwest highlands and its bearing on the chronological classification of the Lewisian. Quarterly Journal of the Geological Society of London, 106, 241–307.
15. Thomson, M. W. H., & Westbrook, G. K. (1982). A gravity investigation of the deep structure of the Lewisian rocks of Gairloch, Wester Ross. Scottish Journal of Geology, 18, 177–185.
16. Winchester, J. A., Park, R. G., & Holland, J. G. (1980). The geochemistry of the Lewisian semipelitic schists from the Gairloch District, Wester Ross. Scottish Journal of Geology, 16, 165–179.
17. Wikipedia. (Accessed on 9th July 2013). Retrieved from https://www.wikipedia.org
Published
2021-01-29
How to Cite
[1]
O. Sikazwe and C. Mdala, “Effectiveness of Transient Electromagnetics in Mineral Deposit Exploration: A Case Study of the Kerry Road Cu-zn-au Sulphide Deposit, Northwest Scotland”, Journal of Natural and Applied Sciences, vol. 1, no. 1, pp. 64-76, Jan. 2021.
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