Extension of the Najd Shear System from Saudi Arabia to the central eastern desert of Egypt based on integrated field and LANDSAT observations

摘要: The Najd Shear System in Saudi Arabia extends over 1200 km a NW-SE direction and has width of approximately 300 km. A digital color mosaic, compiled from seven Landsat thematic mapper scenes, was used to delineate characteristic structural features the Midyan region search for similar Egyptian Eastern Desert. mosaic generated using ratios bands (bands 5/4 × 3/4, 5/1, 5/7) that are sensitive rock content Fe-bearing aluminosilicates, spectrally opaque phases, hydroxyl-bearing or carbonate minerals, respectively. covers 130,000 km² late Proterozoic exposures Arabian-Nubian Shield Desert placed their approximate pre-Red Sea locations. Ajjaj Zone (AJZ) marks termination against eastern margin Red region. AJZ aligns with central Desert, based on analysis Analyses data field observations show exhibit following common: (1) outcrops generally elongate as result folding, fine-scale lithologic heterogeneity at outcrop scale related deformation associated faulting; (2) NW trending left-lateral faults ductile shear zones; (3) subhorizontal, mineral lineations, variably dipping foliations, local changes attitude around large competent (e.g., granitic) bodies; (4) contacts tectonic nature faulting. These less common north south both Results consistent extending into dominating patterns within part