HYDROCARBON POTENTIAL OF THE INTRACRATONIC OGADEN BASIN, SE ETHIOPIA

The intracratonic Ogaden Basin, which covers one-third of the Democrat ic Republic of Ethiopia, developed in response to a tri-radial rift sy stem which was active during Late Palaeozoic to Mesozoic times. Thick Permian to Cretaceous sequences, which principally occur in the SW and central parts of the basin, have proved petroleum potential. Reservoi r rocks are mainly Permian to Lower Jurassic sandstones (the Calub and Adigrat Formations), and Callovian limestones (the Upper Hamanlei For mation). Source rocks are organic-rich Permian, Lower Jurassic and Cal lovian-Oxfordian lacustrine and marine shales. This paper reviews the petroleum geology of the Ogaden Basin and assesses potential explorati on targets. Successful exploration can be expected in view of the rece nt discovery of the Calub gas and gas/condensate field, and the occurr ence of significant shows in the centre of the basin together with see ps along the margin.