Oil Prospects of the Kom Ombo Basin, Upper Nile Valley, Egypt: A Case Study

摘要

The Kom Ombo Basin is one of the recently discovered petroliferous intracratonic basins in the Upper Nile Valley of Egypt, characterized by its high oil and gas potentialities. Rock-Eval pyrolysis in addition to biological marker properties of the Mesozoic-Tertiary shale successions revealed that the crude oils of the Kom Ombo Basin are probably generated from the excellent shale source rock potentials within Lower-Upper Cretaceous succession. This section contains kerogen type-Ⅱ mainly inertinite, capable of generating waxy hydrocarbons. The biomarker characteristics of the Lower and Upper Cretaceous extracts characterized by low oleanane index which was found to be less than 5%, higher gammacerane index up to more than 20% and higher homohopane index reaching more than unity, indicate highly saline, reducing and deep marine environments with minor terrestrial higher land plants input.Kom Ombo oils are generated probably from distinctly mature source rocks of Cretaceous age which is characterized by the higher maturity parameters of sterane isomerization ratios C_(29)αββ/(αββ+ ααα) of 0.63 and C_(29)ααα 20S/(S+R) sterane ratio of 0.56. The correlation between the Rock-Eval pyrolysis data and their biological marker properties revealed that the crude oils of the Kom Ombo Basin are probably sourced from highly mature Lower to Upper Cretaceous source rocks which reached the mid to late mature stage of oil generation at vitrinite reflectance measurements between 0.7-1.35 Ro% between 80 and 50 Ma.