Unconventional hydrocarbon resources of Egypt
摘要
Unconventional hydrocarbon resources have evolved as an important component of global energy policies; however, their potential in Egypt remains underexplored. The unconventional hydrocarbon resources in Egypt are distributed across the Western Desert, Gulf of Suez as well as the Eastern Desert regions, including oil shale, weathered or fractured basement rocks, tight carbonate reservoirs, and shale gas. Advances in extraction techniques like hydraulic fracturing, in addition to horizontal drilling, have opened up previously inaccessible unconventional plays, creating significant opportunities for hydrocarbon production. Egypt hosts several significant formations with untapped potential, including the Thebes Formation, Brown Limestone, weathered and fractured basement rocks in the Gulf of Suez Basin, as well as the Khatatba, Abu-Roash, Apollonia, and Alam El-Bueib formations in the Western Desert. In addition, the Duwi and Dakhla formations, particularly in the Eastern Desert (Quseir–Safaga region), hold the largest and most promising oil shale resources. Recent exploration campaigns in Egypt have improved the knowledge of reservoir quality and reserve estimates using modern fracturing techniques. Methods integrate well log interpretation, Rock–Eval pyrolysis, total organic carbon (TOC) analysis, vitrinite reflectance (Ro), and petrophysical evaluation to assess the hydrocarbon potential of Egypt’s unconventional formations. The Jurassic Khatatba Formation contains Type II/III kerogen with TOC values ranging from 1 to 33 wt% and Ro of 0.8–1.1%, indicating favorable hydrocarbon-prone maturity. The Apollonia Formation is a tight chalky limestone, with porosity ranging from 10 to 40%, vertical permeability between 0.01 and 0.13 mD, and horizontal permeability between 0.03 and 1.1 mD. Its low permeability (~ 1 mD) highlights the necessity of stimulation techniques such as hydraulic fracturing to enhance recovery. The Abu-Roash “F” Member is characterized by high organic content, with TOC values varying between 1.5% and 6.0%. Petrophysical analysis confirms its unconventional reservoir nature, with porosity of 1–3% and permeability below 0.01 mD, also requiring hydraulic fracturing for effective production. In the Western Desert, the Alam El-Bueib Formation shows shale TOC contents between 0.5% and 7.0%, reflecting poor to excellent organic richness. In the Gulf of Suez Basin, the Brown Limestone averages 3.5% TOC, coupled with a high hydrogen index and low oxygen index, indicating Type I/II kerogen dominance. Further south, the Duwi and Dakhla oil shales demonstrate significant hydrocarbon potential, with localized horizons in the Quseir–Safaga area recording TOC values up to 24%. Similarly, the Eocene Thebes Formation, deposited during the Tethyan transgression, contains predominantly Type I/II kerogens with an average TOC of 3.2%, generating hydrocarbons of low API gravity. These findings highlight the multi-play unconventional potential of Egypt, emphasizing the role of integrated geoscience approaches in identifying future exploration targets. The results contribute to Egypt’s broader strategy of energy diversification and long-term energy security.