Integrated organic petrographic and geochemical analyses were made on organic-rich marine carbonate and mixed clastic-carbonate rocks of Middle—Late Jurassic and Early Cretaceous age from the Shushan Basin, Egypt to evaluate their hydrocarbon potential. Analyses allowed the identification of depositional settings, paleoclimate, and three third order genetic stratigraphic sequences SQ with deposits assigned to highstand HST , lowstand LST and transgressive systems tracts TST.
Deposition of the source rocks in the rifting Shushan Basin resulted from the interaction between Neotethyan sea level changes, tectonic, and climate. The good reducing conditions developed during the Neotethyan Middle—Late Jurassic Bajocian—Kimmeridgian second order sea level rises and the climatically induced carbonate sedimentation resulted in the deposition of the organic-rich carbonates of the Khatatba Formation SQ 1, early—middle TST in inner—middle shelf settings under anoxic—dysoxic conditions.
The Late Jurassic late Kimmeridgian uplifting resulted in the deposition of the organic-lean mixed clastic—carbonate strata of the Masajid Formation SQ 1, latest TST in the same shelfal and reducing conditions, which experienced a notable dilution of organic matter. The late TST deposits of SQ 1 are good to very good oil-producing source rocks, where they show average good to very good generative potential of late mature late oil-to early wet gas-window highly oil-prone organic matter.
The Early Cretaceous Valanginian—Albian uplifting associated with the rifting of the Shushan Basin overprinted the Neotethyan late Valanginian—Hauterivian second order sea level rises, Aptian second order highstand sea level, and Albian second order sea level rise.
This is supported by the new discoveries and production of 8, barrel of oil per day BOPD from the Meleiha concessions in the Western Desert Eni, The Western Desert is made up of several extensional rift basins, including the costal basins Alamein, Matruh, and Shushan, in addition to the Abu Gharadig, which lies to south of the coastal basins holding a more interior position Figure 1.
