A New Regional Assessment of The Petroleum Potential in Ethiopia

Tadesse, Ketsela¹, G. R. Keller² (1) University of Texas at El Paso, El Paso, TX (2) University of Oklahoma, Norman, OK

Economic factors dictate that Ethiopia must increase oil and gas exploration and production in its five known sedimentary basins and identify new exploration target areas. Sedimentary rocks cover more than thirty percent of the country that includes the Mekele, Metema, Abbay (Blue Nile), Gambela, and the Ogaden basins, as well as, parts of the Ethiopian rift. However, exploration activities have been limited to the Ogaden basin, which is located in the eastern part of the country. The other basins are either unexplored or lightly explored due to geologic complexity and logistics problems. Most of the sedimentary basins of Ethiopia are related to the breakup of Gondwanaland during the Permo-Triassic. They contain Paleozoic and Mesozoic sediments, which are important hydrocarbon bearing zones in the country. Some of these rift basins were modified by the modern Ethiopian rift, which may have created additional trapping mechanisms. We have used regional gravity data along with seismic refraction and reflection profiles together with remote sensing data and digital elevation maps in a new regional assessment. Our interpretation of seismic reflection data from the Ogaden basin reveals sedimentary pinchouts and channel deposits that are possible hydrocarbon traps and were not the focus of previous exploration activities. In the modern rift, regional gravity models indicate a sedimentary layer that is greater than 2 km thick is present. These sediments and the link between the Ogaden and Abbay basins suggested by our analysis are potential new exploration targets. New drilling results also confirmed the existence of deep basins.