Mapping Archean Greenstone-hosted Deposits With Probability Ratio And Weights Of Evidence Models, Quadrilátero Ferrífero, Brazil

GIS modeling involves the application of one or more computer methods in other to find new or old targets and improves the understanding of mineral environments. This play a very interesting role and design interesting scenarios in regions like the Quadrilátero Ferrífero (QF), one of the most important gold provinces in the world and a major factor in the economic development of Brazil. This paper focuses mainly the application of the probability ratio and weights of evidence techniques on predicting the distribution of Archean greenstone-hosted gold deposits in the Rio das Velhas Greenstone Belt, Quadrilátero Ferrífero. These probability ratio and weights of evidence models use the spatial distribution of host rocks and mineral occurrences to calculate different multi-map signatures for gold mineralization. The ability of these models to predict regions favorable for economic gold mineralization was verified by comparing them with the occurrences of Archean-greenstone-hosted gold deposits and host rocks. Several models that delineate highly prospective areas were determined. From the regional perspective, the predictive geophysical models convincingly define important host rocks. Most importantly, the predictive models generated for the different mineralized environments delineate prospective areas mapped outside the known mines. These areas have the potential to contain similar mineralization.551556Alkmim, F.F., Marshak, S., Transamazonian orogeny in the southern são francisco craton region (1998) Precambrian Research, 90, pp. 29-58. , Minas Gerais, Brazil: evidence for Paleoproterozoic collision and collapse in the Quadrilátero FerríferoBonham-Carter, G.F., (1994) Geographic Information System for Geoscientists - Modeling with GIS, p. 398. , PergamonBonham-Carter, G.F., Agterberg, F.P., Wright, D.F., Weights of evidence modeling: A new approach to map mineral potencial (1989) Statiscal Minerals in Earth Sciences. Geological Survey of Canada, pp. 171-183. , Paper 89-9Ladeira, E.A., (1980) Metallogenesis of Gold at the Morro Velho Mine, and in Nova Lima District, p. 272. , Quadrilátero Ferrífero, Minas Gerais, Brazil. London. University of Western Ontario. Ph.D. thesisLee, G.K., McCafferty, A.E., Alminas, H.V., Bankey, V., Elliot, J.E., Frishman, D., Knepper Jr., D.H., Van Gosen, B., (2001) Geoenvironmental Assessment of Montana: United States Geological Survey Digital Data Series DDS-6