Stratigraphic and Paleoenvironmental Studies on the Lower Eocene Succession at El-Guss Abu Said Plateau, Farafra Oasis, Western Desert, Egypt

Abstract

The Lower Eocene Succession at El-Guss Abu Said Plateau was examined to determine the paleoenvironments and nature of deposition based upon benthic foraminiferal biofacies. Lithostratigraphically, this succession consists of the Esna Formation (shale) at the base, the Nusf Formation (well-bedded marl with occasional limestone ledges), and the Farafra Formation (limestone) at the top. The Esna Formation is an outer shelf-upper bathyal facies rich in planktonic and deeper-dwelling smaller benthic foraminifera. The Nusf Formation and the Farafra Formation are rich in Nummulites and Alveolinids, indicating a carbonate platform facies. Three benthic foraminiferal biofacies, combined with the lithology of the rock units, indicate progressive shoaling, likely associated with tectonic uplift that occurred during the early Eocene in the El-Guss Abu-Said area.