THE RED SEA ‐ GULF OF ADEN: RE‐ASSESSMENT OF HYDROCARBON POTENTIAL Abstract†

Abstract

THE results and conclusions of the UNDP/World Bank Red Sea ‐ Gulf of Aden Regional Hydrocarbons Study Project (June. 1989‐January, 1992) are summarised. These results were derived from detailed examination of pooled public‐sector date provided to the project by the participating bordering states in the region; these included samples and logs from ca. 56 wells drilled in the two basins (out of a total of 71 wells). and some 30,000 line‐kms of reflection seismic (out of 110.000 km available). well‐logs were digitised and correlated, and basin‐wide biostratigraphic, lithostratigraphic and paleoenvironmental studies, source‐rock organic richness. quality and maturity studies and sedimentological analyses were performed by contracted specialist staff in UK and France, and integrated with basin‐wide seismic structural and isopach mapping for selected regional reflectors/intervals by national task forces in Cairo under project supervision: academically‐derived crustal seismic and other geophysical data, and supervision; academically‐derived crustal seismic and other geophysical data, and industrially‐derived velocity and other borehole data were also integrated for the Red‐Sea.Modelling, utilising recently‐acquired geophysical data, indicates crustal asymmetry for the Red sea rift, with oceanic crust of pull‐apart basin type flooring some portions of offshore Egypt and Sudan on the west, and stretched continental crust underlying the eastern Arabian flank. These results suggest that sinistral strike‐slip processes controlled the intial break‐up of the Arabian Plate shaping the African flank as a sharp plate boundary,. Similar processes appear to have initially shaped the Somalia flank of the Gulf of Aden Rift. Only later did true sea‐floor spreading propagate: 10–12 million years age in the eastern Gulf of Aden; and <ca.5 million years age in the western Gulf of Aden, Afar and the southern/central Red Sea. Biostratigraphic work shows deep subsidence and ocean‐water inundation commenced in the late middle Oligocene in the Gulf of Aden, in the late Oligocene in the southern Red Sea, and in the early Miocene in the central Red Sea/Gulf of suez.