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The emplacement and exhumation of gneissic domes of continental lithospheric fragments within the Pan-African oceanic crust in the Arabian-Nubian shield have been subjects of debate in the recent literature. The Wadi Hafafit culmination is one of the largest metamorphic dome complexes, not only in the Eastern Desert, but also in the Arabian-Nubian shield. The culmination forms a northwest-trending folded belt including five individual gneissic domes that show complex interference fold patterns, bounded by northwest-to west-northwest-trending marginal shear zones (the Nugrus and Hafafit shear zones), which belong to the late Proterozoic Najd fault system in the Eastern Desert of Egypt. The Hafafit metamorphic dome forms a positive flower structure that is characterized by a vertical stretch in the central part with subvertical foliation at the individual dome peripheries, subhorizontal flattening in the roof, and near simple shear at the complex margins defined by the Nugrus and Hafafit shear zones. This study presents arguments concerning the folding pattern and exhumation of the culmination and its relation to sinistral, transpressional kinematics along the branches of the Najd fault system. The folded axial surfaces of the gneissic domes are interpreted in terms of interference of two fold generations: (1) an early fold generation that developed east-northeasttrending axial surfaces, which may have formed during late Pan-African northwestward nappe stacking, and (2) a late fold generation that developed north-south-trending fold axes that deformed the axial surfaces of the first fold generation, and probably associated with sinistral shearing on the Nugrus and Hafafit shear zones. The fold interference patterns associated with exhumation of the Hafafit gneissic domes are consistent with published geochronological data and the tectonic evolution of the Arabian-Nubian shield.

Rock foundations of the Kephren and Kheops pyramids are examined in comparison with other Fourth Dynasty monuments: the Sphinx, Queen Kentkawes' monument and the Abu Rawash monument. This study is based on geological and topographical observations, photomontages and field measurements. The results, which are correlated with those of former studies, demonstrate the existence of natural hills used as substrata in the construction of the two great pyramids. The minimum volume of these hills can be estimated at 12% and 23% respectively of the volumes of the Kephren and Kheops pyramids. The use of worked rock hills appears to be a construction method under the Fourth Dynasty. Etude géologique et topographique de la colline originelle à la base des monuments de la quatrième dynastie égyptienne du plateau memphiteMots-clés. -Colline originelle, Pyramides égyptiennes, Stratigraphie, Topographie.Résumé. -Le substratum rocheux des pyramides de Kheops et Khephren est étudié en comparaison avec celui d'autres monuments de la quatrième dynastie de l'ancienne Egypte : le Sphinx, le monument de la reine Kentkawes et le monument d'Abu Rawash. Cette étude est basée sur des observations géologiques, topographiques et des photomontages, ainsi que des mesures réalisées sur le terrain. Les résultats, corrélés avec ceux d'études antérieures, démontrent l'existence de collines naturelles utilisées comme assises pour la construction des deux grandes pyramides. Le volume minimum de ces collines peut être estimé par rapport au volume total à 12 % pour Khephren et 23 % pour Kheops. L'utilisation de collines rocheuses pour asseoir la construction d'un monument apparaît comme une des méthodes de construction utilisées sous la quatrième dynastie.

The Eastern Desert of Egypt suffered a protracted period of deformation triggered by cratonization of the new juvenile crust known as the Arabian Nubian Shield (ANS), which has been proposed for potential gold discoveries associated with the corresponding tectonic event. The Fatira area, on the border of Egypt's Northern and Central Eastern Deserts, is covered with metavolcanic rocks twisted by a dextral relocation of the Fatira Shear Zone (FSZ) relative to the Barud magmatic body. The recent study evaluated many deformed post‐orogenic granitic intrusions and felsite dikes associated with promising mineralization localities, notably orogenic gold deposits. The combination of various field observations and remote sensing data, followed by the analysis of aeromagnetic enhanced maps, allowed the differentiation of distinct lithologies, structural features, and hydrothermal alterations in the study area. Additionally, the integrated results obtained from the different interpretation techniques are utilized to identify and confirm the previously supposed mineralized localities in the Fatira and Abu Zawal areas and predict other matched localities. The final ASTER, Sentinel 2 hydrothermal alteration, and orientation entropy heat maps demonstrate the association between these mineralized regions and major structures related to the FSZ late stage of deformation rather than other structures studied throughout the area of interest.