Concludes that the formation of the Gulf of Suez depression was preceded by regional updoming, accompanied by block faulting along pre-Cretaceous northeast-southwest fault zones, in north Egypt and Sinai during the Eocene. Stretch faults developed as a result of the updoming. During crustal movements which continued at least until the Pleistocene, grabens were formed by blocks bordered by faults which were converging downwards, and horsts by blocks bounded by diverging faults.