Late Neoproterozoic structural dynamics in the Egyptian Nubian Shield: evidence from the Queih shear belt

Abstract This study investigates the geological architecture and tectonic evolution of the Queih shear belt, located in the Central Eastern Desert of Egypt, within the Egyptian Nubian Shield. An integrated approach combining multi-sensor satellite remote sensing (Landsat-8, ASTER, Sentinel-1 A), aeromagnetic data analysis, and systematic field investigations was employed to delineate lithological units, structural features, and deformation phases. Advanced image processing and Enhanced Horizontal Gradient Amplitude (EHGA) techniques enabled precise mapping of lithological contacts, faults, folds, and shear zones. The results reveal that the Queih shear belt is a complex horst structure of Precambrian basement rocks, bounded by major normal faults and affected by a polyphase tectonic history. Four principal ductile deformation episodes (D1–D4), followed by Phanerozoic extensional tectonics (D5), are documented, involving NNW–SSE and ENE–WSW compression, transpressional shearing, and alternating dextral and sinistral strike-slip faulting related to the Najd Fault System. The spatial and temporal relationship between molasse sedimentation and phases of wrench faulting is highlighted, providing new insights into the interplay between sedimentation and tectonic reactivation during the late Neoproterozoic. This work refines geological maps of the region and advances understanding of crustal processes the Egyptian Nubian Shield.