SUBSURFACE LOWER–MIDDLE MIOCENE BIOSTRATIGRAPHY OF RAS EL-USH OIL FIELD, G. ZEIT AREA, GULF OF SUEZ, EGYPT

The Lower-Middle Miocene succession penetrated in four wells in Ras El Ush oil field (Ras El Ush 7,8,12 and 14), East G. Zeit, Gulf of Suez is examined in detail for its foraminiferal and nannofossil contents. The Rudeis, Kareem and Belayim formations are distinguished. One hundred and fifty-one foraminiferal and forty-five nannofossils species are identified. Three planktonic foraminiferal and two nannofossils biozones are distinguished and integrated. The planktonic foraminiferal zones are Catpsydrax dissimilis (M3) of early Miocene (Burdigalian) age, Praeorbulina sicana (M5) of early-middle Miocene (Burdigalian-Langhian) age and Fohsella peripheroacuta (M7) of middle Miocene (Serravallian) age. The nannofossil biozones are Sphenolithus belemnos Zone (NN3) of early Miocene (Burdigalian) age and Helicosphaera ampliaperta Zone (NN4) of early Miocene (Burdigalian)to middle Miocene (Serravallian) aga.