ABSTRACT
The main part of Egypt west of the river Nile is covered by thick sequences of relatively undisturbed sedimentary strata of Paleozoic, Mesozoic and Cenozoic age. Apart from the Eastern Desert, Precambrian and younger crystalline rocks occur only in southern Egypt where they occupy an area of some 40 000 km2. The majority of these rocks crop out in the Gebel Uweinat area at the junction of the borders of Egypt, Sudan and Libya. Numerous smaller basement areas are exposed between Bir Safsaf and Lake Nasser. Generally, the basement is close to the surface everywhere in that region, except between Gebel Kamil and Bir Safsaf where a downfaulted graben, the Bir Misaha trough, is filled with about 700 m of Nubian sediments (Schneider & Sonntag 1985). The basement high that separates the deep intracratonic Dakhla basin from the more shallow basins of North Sudan is referred to as the Uweinat-Bir Safsaf-Aswan Uplift.
