The Egyptian region of the Red Sea depression attained its present configuration primarily as a result of epeirogenetic movements acting differently on its various parts. Distribution of sedimentary facies was controlled by the types and the duration of these movements. The sector of the mountainous basement-complex sub-region between the Red Sea and the Wadi Qena area to the west is characterized by upper Cretaceous and Tertiary clastics and limestone, with some phosphate in the Maestrichtian (upper Cretaceous) overlying the sole. During late Cretaceous and early Tertiary time, a major fault along the west edge of the Red Sea range dropped the Wadi Qena area, which was transgressed from the north by the sea. A similar major fault developed along the east edge of the Red Sea range in early Eocene to pre-middle Miocene time, dropping the area to the east, and leaving the range as a horst uplifted in the middle Miocene. East of the horst, a series of step faults ranging in age from post-early Eocene to Quaternary developed. The Red Sea graben thus resulted from a series of tectonic movements instead of one.

You do not currently have access to this article.