An application of lithogeochemistry to the evaluation of the Ni-sulphide ore potential of weathered serpentinites in the Fortaleza de Minas Greenstone Belt,Minas Gerais,Brazil |
| |
| Institution: | 1. CSIRO Mineral Resources, Australian Resources Research Centre, Kensington, WA 6151, Australia;2. Earth and Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, NSW 2052, Australia;3. Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran;4. Department of Computer Science, Applied Mathematics and Statistics, University of Girona, Girona, Spain;1. School of Earth and Environmental Sciences and Williamson Research Centre for Molecular Environmental Science, The University of Manchester, Williamson Building, Oxford Road, Manchester M13 9PL, UK;2. Department of Environmental Science, Royal University of Phnom Penh, Phnom Penh, Cambodia;3. Faculty of Agricultural Economics and Rural Development, Royal University of Agriculture, Phnom Penh, Cambodia;4. British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG, UK;5. ETH Zurich, Institute of Geophysics, Sonneggstrasse 5, 8092 Zurich, Switzerland;6. Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK |
| |
| Abstract: | A practical application of lithogeochemistry to the classification of weathered serpentinites as to whether or not serpentinites are host rocks to Ni-sulphide ore is presented. An effort is made to apply existing concepts used to distinguish between fertile and sterile unweathered ultramafics to explain the observed chemical differences between fertile and sterile weathered serpentinites in southwestern Minas Gerais, Brazil.The data comprise total-attack chemical analyses for Al, Ca, Cr, Cu, Fe, Mg, Mn, Ni, Si, Ti, V, and partial-attack determinations of Cu and Ni as ascorbic acid, hydrogen peroxide-soluble metal. Student's t-tests are used to identify element concentration differences between the two serpentinite groups. Discriminant analysis is used to classify the weathered fertile and sterile serpentinites. Non-linear mapping and fuzzy c-means clustering help to assess the validity of the discriminant analysis. Finally, chemical element associations provide extra information on geological and mineralogical causes that can be responsible for the identified differences.It is found that a clear separation and classification of weathered serpentinites is possible using the procedures presented. The observed chemical differences between fertile and sterile serpentinites are interpreted in terms of original magmatic differentiation, the degree of sulphur saturation of the original magma and the behavior of the derived ultramafic rocks in a tropical weathering environment. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
