GIS based mapping of metallogenic anomalies in the Bana granitic complex of West Cameroon integrating remote sensing analysis field observations and geochemical data
摘要
Mineral prospectivity mapping in poorly explored Precambrian terrains is complicated by thick forest cover, paucity of outcrops, poly-deformed tectono-magmatic histories and scarcity of high-density geophysical and geochemical data. These limitations dramatically limit the effectiveness of classical single-criterion (often purely data-driven) approaches that tend to depend on large training set and are not able to adequately consider geological uncertainty in poorly sampled regions. To overcome such challenges, this study examines the metallogenic implications of the Bana granitic rocks in western Cameroon, i.e., within the Pan-African Central African Orogenic Belt, using an integrated approach of Landsat 9 OLI–based alteration mapping, field work investigation geochemistry data analysis, GIS methodologies and fuzzy-logic modeling. The Bana zone, a fragment of the Pan-African Central African Orogenic Belt, is known for its complex granitic intrusions and contains a series of mineralized zones with probable economic interest. This study, in conjunction with field verification, geochemical discrimination diagrams, and GIS analysis, unveils the spatial distribution patterns of the metallogenic anomalies and their genetic interpretations. The footprints of hydrothermal alteration halos and geochemical signatures are very clear in the data, providing evidence that potentially mineralized zones of elements such as Fe, Al, Ti, Ga, Zn, and REEs might exist. The integration of multidisciplinary techniques confirms the role of Bana granites as metallogenic markers within the Central African metallo-tectonic domain.