Integrated remote sensing and petrological study of garnet-bearing rocks in the Arabian-Nubian shield: a case study from Wadi Shait-Wadi Gemal area, South Eastern Desert, Egypt

The Wadi Shait-Wadi Gemal district, within the Hafafit metamorphic dome of Egypt's South Eastern Desert, represents a structurally complex segment of the Arabian Nubian Shield where garnet-bearing rocks are difficult to distinguish using conventional mapping. This study addresses this issue by integrating multi-sensor remote sensing (Landsat-9 and ASTER) with detailed field and petrographic investigations. Advanced image processing techniques, including false color composites (FCC), principal component analysis (PCA), minimum noise fraction (MNF), and proposed band ratios (BRs), were applied to enhance lithological discrimination and improve the detection of garnetiferous units. Field and petrographic analyses confirmed three principal garnet-bearing lithologies: garnet-muscovite-biotite schists, psammitic gneisses, and pegmatites. Garnet porphyroblasts were observed within quartz-mica matrices, reflecting a complex metamorphic history involving multiple deformation phases. The integration of remote sensing with petrological data allowed the production of a refined geological map and the precise delineation of garnet-enriched zones. This combined approach proved effective in resolving lithological complexities and significantly improves the understanding of garnet distribution in Precambrian metamorphic terranes.