Biostratigraphic and Paleoenvironmental Implications of Eocene Ostracods from Wadi Tayiba -Wadi Nukhul area, West -Central Sinai, Egypt

Abstract

Investigation of the ostracod faunas recovered from two outcrop sections representing the Eocene succession at Wadi Tayiba an d Wadi Nukhul in west central Sinai area yielded 47 species and subspecies belonging to 21 genera and 12 families. The ostracod faunal diversity and abundance are fairly high in the middle part of the two sections (Darat and Khaboba Formations), however dr amatically decrease in the lower part of the two sections (Thebes Formation) as well as the upper part of the Wadi Tayiba section (Tanka Formation). Biostratigraphic evaluation of the recorded faunas revealed that the recorded assemblage is typically a Mid dle Eocene assemblage. The early Middle Eocene (Lutetian) and late Middle Eocene (Bartonian) intervals are distinguished by different ostracod species. The recorded ostracod faunas are entirely comprised of marine taxa. They implicate that the studied succession was deposited in marine environment, under inner to middle neritic environmental settings with transient intervals displaying a deeper outer neritic setting.