文摘
Miocene siliciclastic-carbonate deposits are widely exposed in Cairo-Suez District, Egypt. These deposits are underlain and overlain by continental sediments of Oligocene and post Miocene, respectively. Three stratigraphic sections were investigated at Gabals Geneife, Homeira and Gharra. Lithostrtigraphically, the Miocene sequence could be differentiated into two main rock units representing shallow deposits with relatively intermittent deep marine incursions. These are from base to top, Gharra Formation and Genefe Formation. Detailed macrofossils investigations led to the recognition of four macrofossil zones, namely Alectryonella plicatula-Crassostrea frondosa Range Zone, Echinolampas amplus-Scutella ammonis Range Zone, Chlamys (Macrochlamys) sardoa-Chlamys (Argopecten) submalvinae Range Zone, and Chlamys gentoni-Pecten (Oppenheimopecten) benedictus-Pecten (P.) ziziniae Assemblage Zone. Microfacies analysis and identified taxa indicated that the Miocene sequence was deposited in transgressive-regressive cycles ranged from near shore, warm shallow inner to middle shelf marine environments with storm influence during the accumulation of the oyster banks.