Integration of remote sensing and geophysical data for the extraction of hydrothermal alteration zones and lineaments; Gabal Shilman basement area, Southeastern Desert, Egypt

Abstract

In the Gabal Shulman area of the southeastern desert of Egypt, ASTER and geophysical aeromagnetic data provide useful information for detecting hydrothermal alteration zones and structural features at the surface and subsurface. The band ratio of the data from ASTER, constrained energy minimization (CEM) and Crósta algorithms help to identify new potential alteration zones in the study region. The aeromagnetic data were used to enhance the exploration study in the study area. The Horizontal Gradient Magnitude (HGM) filter was used to map the lineaments in the area. The statistical analysis of the lineaments shows that the main directions controlling the study area are northwest, north, north-northeast, and northeast. Finally, the results of ASTER and the geophysical aeromagnetic data show the presence of new hydrothermal alteration zones in the study region. These alteration zones are mostly associated with two main structures trending NNW-SSE and N-S, mainly along tectonic shear zones (thrust faults) and contacts between serpentinites and basic metavolcanics.