Petroleum System in the Shushan Basin: A Mature Basin Leading to Future Exploration in the Western Desert of Egypt

Mohamed Abdel-Aziz Younes
Geology Department, Faculty of Science, Alexandria University, Egypt

Shushan Basin is one of the coastal basins in the Western Desert of Egypt that characterizes by its high oil and gas potentialities. Rock-Eval pyrolysis, biomarker characteristics of crude oils and related source rocks revealed two types of extracts (A) Alam El-Bueib and Abu Roash-G and (B) Khatatba Formation and two families of crude oils I and II of similar stable carbon isotope composition. Fair correlation can be made between type (A) extracts and Bahariya crude oils, where the similar biomarker properties among them suggest that these crude oils were generated from terrestrial land plants influence at low thermal maturity level. Meanwhile, type (B) extracts and Alam El-Bueib crude oils are genetically related and bear the same terrestrial source input generated at higher thermal maturity level than those of Alam El-Bueib and Abu Roash -G source rocks. Organic rich source rocks with excellent potential to generate oil are present in the Middle Jurassic Khatatba Formation entered the late mature stage of oil generation window at vitrinite reflectance between 1.0 and 1.3 Ro% during the Late Cretaceous. Meanwhile, a good to fair source rocks of Alam El-Bueib and Abu Roash-G Member located within the early to mid mature stages of oil generation window between vitrinite reflectance 0.5 to 1.0 Ro% between Late Cretaceous to Late Eocene. Biomarker similarities of crude oils and source rock extracts may be related to the stratigraphic as well as structrural entrapment elements that play an important role during the hydrocarbon accumulations in Shushan Basin.