الفهرس 
Geological settingOnly 14 pages are availabe for public view
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Abstract
The crystalline basement complex of Egypt forms the western part of the Arabian-Nubian Shield and occupies the - southern part of the Sinai Peninsula and a triangular area in the Eastern Desert-that widens southwards to cover the whoLe width of the Eastern Desert at about the latitude of Aswan. The area under consideration comprises about 466 km2 of the crystalline basement rocks between W. Abu Ghusun and W. Khashir, south Central Eastern Desert. The Precambrian belt of the Eastern Desert of Egypt is composed of Upper Proterozoic volcano-sedimentary complex containing scattered mafic-ultramafic bodies and intruded by syntectonic to late tectonic granitoid batholiths (Older Granites). This generalized sequence is followed by later calc-alkaline volcanics (Dokhan Volcanics) and unconformably overlain by molasse-facies sediments (Hammamat Group). These sediments are cut by post tectonic Pan-African granites (Younger Granites). Analogous units are exposed in a much part of western Saudi Arabia, north-eastern Sudan and northern Ethiopia. The ages range from 788 (age of crystallization of oceanic crust, Ries and Darbyshire, 1984) to 550 m.y. A major episode of igneous activity occurred at 580 m.y. with the emplacement of numerous (Pan-African) granitic plutons (Fullagar and Greenberg, 1978) . Before attempting to construct a modal for the evolution of the area it may be convenient to review briefly the suggested sequence of rock units and their inferred tectonic setting (Table 12-1).