The Petroleum Geology of Egypt and History of Exploration

Abstract

Egypt has proven gas reserves as of the end of 2016 of 16.9 BBOE (98 TCF) and oil and condensate reserves of 18.5 BBO, with an estimated yet-to-find that may exceed 224 TCF (38.6 BBOE). Exploration activity, particularly in the offshore Nile Delta and Mediterranean, continues to add new giant field discoveries which extend eastward into the Levant Basin. Egypt’s geological history is complex, with multiple phases of basin formation resulting in working petroleum systems from Paleozoic through Pliocene strata. The Gulf of Suez, Western Desert and Nile Delta are the most prolific provinces. Upper Egypt and the Red Sea offer additional potential, as do poorly understood basins across Upper Egypt. The oldest proven potential source rocks are in the poorly imaged Carboniferous basins in the Western Desert, hidden beneath the Hercynian unconformity and are thus poorly understood. Their contribution to proven production is unknown and much of the deeper production is attributed to charge from Jurassic or Cretaceous shales via fault juxtaposition with the Paleozoic. Fundamental basement architecture was not understood regionally until country-wide gravity, magnetic and seismic studies were completed in 2001. Deep basin geometries are still being unraveled and modified with thousands of additional wells, new age dating and imaging techniques, most of which remains in proprietary studies in individual companies. Shallower structural trends, however, are certainly strongly controlled these older basement, Paleozoic, and Jurassic and Cretaceous fault systems. Many of the deep structures run oblique to shallower Middle and Upper Cretaceous fabrics, causing the deeper, poorly imaged traps to be missed. Better 2D and 3D seismic has revealed many of the deeper structures, particularly in the Western Desert, opening up new plays. Tertiary trends frequently run perpendicular to the older structures, but have fault transfer zones or other anomalies controlled by the older faults. Pliocene plays are almost exclusively confined to the Nile Delta. Substantial deep reserves have been found in Oligo-Miocene turbidites in the Nile Delta, with high porosity and permeability as deep as 7 km in high pressure-high temperature traps. Upper Egypt Lower Cretaceous rifts are lightly explored, and not extensively covered by either 2D or 3D seismic. Successful Red Sea exploration has been elusive, with only oil and gas shows and recoveries and no commercial fields, but remains an area of high promise. Since 2015, a new play in Miocene and Cretaceous carbonate reefs has developed in the offshore Mediterranean in the Egyptian side of the Exclusive Economic Zone (EEZ) deep water between Egypt and Cyprus and has unlocked the largest gas field in Egypt’s history. This play, long overlooked, is currently the most active and promising exploration frontier in the country and surrounding Mediterranean basins. This chapter provides an overview of Egypt’s petroleum geology, in part by examining the past exploration history, play concepts, changing paradigms and advances in technology which have more almost tripled the country’s reserves in the last 17 years.