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Gabal Gharib area comprises Late Proterozoic Precambrian basement rocks of metamorphic and magmatic assemblages uncomfortably overlain by Miocene-Holocene sedimentary rocks. The calc-alkaline metamorphosed volcanic rocks are the main rock varieties forming the exposed metamorphic assemblage extruded by Dokhan volcanics and intruded by syn to late to post tectonic magmatic intrusions of gabbro-diorite, tonalite-granodiorite (G1), monzogranites-alkali feldspar granites (G2) and alkaline riebeckite granites (G3). Different band ratio ETM images, Landsat ETM-Egyptsat-1 fused image data with the spectral signature characterizations together with the data of field study were applied to discriminate these different basement rock units. Four granitic varieties as well as the metamorphosed older volcanics and younger Dokhan-type volcanics are well discriminated. This study revealed that the Landsat ETM-Egyptsat-1 fused band ratio image (7/4, 3/7, 4/5) is the best to discriminate the exposed basement rocks and the structural features at Gabal Gharib area.