Abstract
The tectonic evolution of the Arabian-Nubian Shield (ANS), the northern continuation of the East African Orogen (EAO), is enigmatic and a matter of controversy. The EAO is observed as a N-S trending major suture zone separating East and West Gondwanaland. It documents a prolonged tectonic history bracketed by the fragmentation of Rodinia Supercontinent and the amalgamation of Gondwana. The ANS is dominated by Neoproterozoic juvenile continental crust (i.e., crust formed directly from the mantle), formed by magmatic arc accretion and subsequent post-tectonic magmatism, and includes a mosaic of tectonic terranes juxtaposed along ophiolite-decorated megashears (suture zones). Among them is the Eastern Desert terrane (namely, Aswan or Gerf terrane in some literatures) which is regarded as the western extension of Midyan terrane in Western Arabian and shows most of the polydeformed history of the ANS. This chapter is devoted to discuss the Neoproterozoic crustal evolution of the Pan-African belt of the Eastern Desert terrane in an attempt to understand the tectonic setting of the ANS. Main points to be discussed in this chapter are: (1) infracrustal-supracrustal rocks, (2) thrusting, shearing, and folding relations; (3) gneiss domes versus metamorphic core complexes; (4) the conjugate pairs of Najd-related shears; (5) role of Najd Fault System in tectonic evolution of gneiss domes; (6) rates and transport directions of metaultramafic nappes; (7) the voluminous intrusives in northern Eastern Desert; (8) the post-amalgamation Hammamat sediments and their relation to Dokhan Volcanics; and (9) the northward decrease in intensity of deformation in the entire Eastern Desert.