Abstract: Geology of Red Sea Margin

E. M. El Shazly

The Red Sea and the Gulf of Suez are dominated by sedimentary rocks ranging in age from the Paleozoic to the Quaternary, interrupted by unconformities of varied importance. The Paleozoic and younger sedimentary rocks are encountered in the Gulf of Suez basin, although Cretaceous and younger deposits still are preserved in the northern Red Sea littoral and the rest of the Red Sea margin essentially is covered by deposits of the middle Miocene and younger. The major unconformities are late Precambrian-early Paleozoic, late Paleozoic-early Mesozoic, late Mesozoic-early Cenozoic, and Neogene-Quaternary. These correspond to the Caledonian, Hercynian, Laramide, and Alpine diastrophisms. The various volcanic rocks interbedded with the sedimentary columns of the Red Sea margin co relate with these tectonic disturbances.

There is strong evidence for the initiation of the Red Sea structure during transition from the last Precambrian megacycle of intense tectonics to the Phanerozoic megacycle of milder tectonism. Precambrian igneous-metamorphic basement rocks in the Red Sea axial trough (St. John's Island) and to a less extent in the proximity of the Red Sea coast have been influenced by alkaline metasomatism. The results of the alkaline metasomatism provide evidence of the effect of Red Sea tectonics on rocks of the late Precambrian-early Phanerozoic transition and during the late Miocene. Although the Red Sea and the Gulf of Suez structures emerged during the late Precambrian-early Phanerozoic transition and were greatly influenced by the history of the Tethys, the influence on the Red Sea ended in th Miocene.

AAPG Search and Discovery Article #90972©1976 AAPG-SEPM Annual Convention and Exhibition, New Orleans, LA