Impact of tectonic and stratigraphic evolution of Shushan Basin on hydrocarbon accumulation, north Western Desert, Egypt

Abstract

Abstract Tectonic and stratigraphic evolution of the Shushan Basin in northern Western Desert of Egypt played an important role in hydrocarbon accumulation in the Mesozoic. The purpose of this study is to assess the hydrocarbon prospectivity of the deep Middle Jurassic Safa Member by integration of seismic interpretation, structural analysis, core descriptions, and wireline log evaluation over ten wells. Seismic data also indicate extensive E–W and NW–SE normal fault systems that developed horst–graben structures, hence providing crucial structural traps. Petrographic observation indicates that the Safa reservoir consists of vertically stacked, pebbly, cross-bedded sandstones deposited in a fluvial channel environment. Petrophysical evaluation indicates net pay thicknesses varying from 375 to 500 ft, 10–15% effective porosity, 5–20% shale content, and hydrocarbon saturation varying up to 95%, particularly in Qasr-3 and Qasr-4 wells. These results confirm the Safa Member as a fault compartmentalized, overlying Zahra shale-sealed, high-productivity gas–condensate reservoir. The findings also stress the significance of tectono-stratigraphic evolution in governing reservoir development and offer an exploration predictive model for such similar rift-related basins worldwide.