Emerging Play Types and Structural Styles in the Equatorial Atlantic Transform Margin of Africa; Case Studies from Deep-Water Ghana and Ivory Coast Basins

Matthew, Olabode S.; Ajayi, Olajumoke; Adigwe, Helen-Nellie

The Equatorial Atlantic Transform Margin of Africa extending from the Western Niger-Delta to the deep-water Sierra Leone basin in a little more than a decade has been a bee-hive of exploration activities and also represents a major frontier of underexplored oil and gas province.

A review of subsurface data spanning the entire margin from Benin, Ghana, Ivory Coast, Liberia and Sierra Leone gives a regional overview of the petroleum system and structural styles prevalent in the area. It is observed that this region is an emerging play for stratigraphically trapped hydrocarbon which has been boosted by the Jubilee discovery in Ghana Tano Basin and several other discoveries in the Cape three point sub-basin.

An evaluation of the petroleum system within this West African transform margin frontier region shows the prevalence of Cretaceous source rocks and abundant clastic reservoir facies made predominantly of turbidites, channels and fan system of Cretaceous and tertiary age. Predominant structural style identifiable includes mainly Graben and Horst structures with perfect examples of stratigraphic plays characterised by multiple pinch outs and onlap surfaces which might be similar to producing plays in the Tano basin where the Jubilee field lies.

This paper attempts to review the identified plays present in the region and the prospectivity that is locked in this deep-water province. Individual examples are showcased from the Cape Three Point basin in Ghana and Ivory Coast basin in Cote' d Ivore.

AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013