Integrating Sedimentology and Sequence Stratigraphy for Reservoir Characterization of the Cenomanian- Turonian Raha and Abu Qada Formations in West Central Sinai, Egypt

Tarek Anan¹, G. Michael Grammer¹, Adam El-Shahat², Adel Genedi², and Essam Sharaf^2
1Western Michigan University, Geoscience Department/MGRRE, Kalamazoo, MI, 49008-5241, [email protected]
²Mansoura University, Geology Department, Mansoura, 35516, Egypt,

Four outcrop locations of the Cenomanian-Turonian rocks in west central Sinai, Egypt have been chosen for standard petrographic analysis for facies and depositional environment interpretation. These rocks are reservoirs for many oil fields in the Western Desert and the Gulf of Suez region. The rocks were deposited in a mixed siliciclasticcarbonate system and contain four principal lithofacies, a) limestones, b) dolostones and dolomicrites, c) shales, and d) sandstones and green sand (glauconites). Deposition was on a homoclinal ramp as indicated by proximal facies (bivalve skeletal wackestone), middle ramp facies (oyster skeletal floatstone and oyster skeletal rudstone), and distal ramp facies (foraminiferal wackestone and calcisphere wackestone). The ramp interpretation is further supported by the absence of biohermal reefs.

A high resolution sequence stratigraphic framework is being developed using a combination of facies stacking patterns and stable isotopic (C/O) trends. The two studied formations are composed of one second-order depositional sequence (10 Ma). This large scale sequence is composed of two third-order depositional sequences that contain several small scale, higher frequency (4^th order) sequences. All sequences are bounded by siliciclastics.

Stable isotopic analysis (C/O) will also be utilized to determine the Cenomanian-Turonian boundary (Oceanic Anoxic Event (OAE)) as a means to correlate with other strata in the southern Tethys region.

AAPG Search and Discovery Article #90095©2009 AAPG Eastern Section Meeting, Evansville, Indiana, September 20-22, 2009