The Petroleum Geology and Exploration Potential of the Western Desert Basin, Egypt

By

Mark Cowgill¹

(1) Robertson Research International, North Wales, United Kingdom

 The Western Desert Basin of Egypt covers an area of over 1,000,000 km², and can be conveniently separated into two regions: north of 29¼ the basin is relatively well-explored and comprises a major Jurassic and Cretaceous depocentre; the south of the basin is relatively underexplored and comprises a series of isolated rifts within a relatively stable craton.

In the north of the basin, proven reservoirs comprise Jurassic sandstones and Upper Cretaceous sandstones and carbonates. Traps are developed in east-west oriented fault blocks and horst blocks. The main source rocks are Upper Cretaceous shales and limestones and Upper Jurassic shales and coals. Source potential is also identified in the pre-rift succession.

Little is known regarding the petroleum geology and potential of southern Egypt. Palaeogeographic reconstructions suggest non-marine sedimentation during the Jurassic may have led to deposition of shales in a number of small, isolated depocentres. A marine transgression during the Cretaceous lead to deposition of shallow marine and shelfal sands across the region. These sands are the main potential reservoir interval.

By combining the extensive information available in the public domain with Fugro Group non-exclusive datasets, the petroleum systems of this basin have been documented and stored digitally. Within the Western Desert Basin, 11 proven reservoir-seal couplets (plays) have been identified. Analysis of the exploration history and pool size distribution for each play was combined with up-to-date knowledge regarding the development and physical extent of the play. The prospective resources (yet to be discovered hydrocarbons) in each play have been estimated.