An integrated approach for mapping mineral resources in the Eastern Desert of Egypt

摘要

Observations of the Earth from space either by satellites or aircrafts are significant approaches for mineral exploration, because of their capability of revealing hydrothermal alteration minerals and sensing the surface/subsurface fracture/fault zones. A study area that is situated in the Pan-African belt of Egypt is tested for targeting potential area of mineral resources involved the hydrothermal system using satellite imagery combined with aeromagnetic, geochemical and field data. Extracted alteration layers using ASTER data and major structures (fault/fracture zones) from DEM, ALOS/PALSAR and aeromagnetic data were prepared and integrated using Knowledge-driven technique in multicriteria-decision making tools for producing-mineral prospect map. The results revealed five predictive areas of expected mineral occurrences ranging from excellent to very low. Spectral analysis using ASTER data allowed defining the key-hydrothermal minerals which revealed three successive zones of alterations e.g., argillic, phyllic and propylitic. Plausible areas of minerals fitting to the ore body representing the center of the extensive alterations. Field, geochemical, and ore microscopic investigations validated the results of integrated data. Field data revealed that the mineralization zones extend along NNE-SSW thrust trend that later modified by NW-SE, N-S and NE-SW strike slip faults. Hydrothermal processes related to later magmatic stages probably were responsible for destruction and remobilization of the primary minerals of the host metavolcanics. Microscopic examination revealed that Fe-Cu-Zn-Pb sulfide minerals are associated with auriferous quartz veins. Plausible areas of prospective interest for possible mineralization also were characterized using geochemical analysis. This study successfully displays the key role of integration approach for exploring mineral resources in arid regions.