Depositional Trends and Sedimentary Environments of the Cenomanian-Turonian Sediments along G. Nezzazat-G. Ekma, South-West Sinai, Egypt

Abstract

The Upper Cretaceous sedimentary succession at G. Nezzazat-G. Ekma, west-central Sinai was examined to detect the depositional trends responsible for its development and discuss the depositional sedimentary environments dominated its evolution. The examined succession spanning from early Cenomanian to Turonian age and consists of three rock units namely from the base; Raha, Abu Qada and Wata formations. The detailed lithological and sedimentological characteristics of the concerned succession revealed that Raha Formation has been subdivided into Abu Had Member and Mellaha Sand Member and diagnostically characterized by the presence of both three clastic and three non clastic microfacies association on the other hand, Abu Qada Formation is characterized also by three clastic and four non clastic microfacies association which indicates deposition of both in a mixed siliciclastic-carbonate system on a ramp setting, whereas Wata Formation is characterized by the dominance of non clastic microfacies. All the recorded microfacies association is described and their sedimentary environments are concluded. The Raha Formation was deposited under progressively advancing subtle sea that reached maximum by the mid-parts of the formation and retreated toward the top part of the formation. Abu Qada Formation was deposited under successively advancing sea started in shallow foreshore conditions and continued deepening toward the top of the formation where outer marine shelf facies dominated. Whereas, the Wata Formation is represents a phase of relatively deep marine sedimentation, mostly within mid-outer marine shelf setting.