Enhanced analysis of hydrothermal alteration and mineral prospecting through integration of ASTER and aeroradiometric data: A case study from the Ouarzazate region, Morocco

Abstract

The study area, situated in the western segment of the Saghro Massif within the Anti-Atlas belt, is characterized by mineralized deposits, intricate lithological formations, and distinctive tectonic features. This research integrates ASTER imagery analysis with gamma-ray spectrometry data to map alteration zones and examine the geochemical and mineralogical processes that influence radioactive element distribution. Specific analytical techniques are applied to investigate relationships among argillic, phyllic, propylitic alterations, iron oxides, and regions with elevated concentrations of radiometric elements. Gamma-ray spectrometry data, including mono-elemental maps of radiometric components (potassium in %, equivalent uranium in ppm, and equivalent thorium in ppm), are analyzed alongside interpreted ASTER images to identify potential mineralization zones. Ratios of K/eU and K/eTh, along with the F parameter, are processed within a fuzzy model framework, which combines these datasets into a comprehensive mineral prospectivity map that serves as a tool for guiding exploration. This analysis identifies four hydrothermal alteration zones as highly promising for mineral exploration, suggesting a likely association between magmatic processes and spatially correlated hydrothermal alteration, thereby supporting further detailed exploration initiatives.