Abstract: Petroleum Geology of Cote D'Ivoire (Abidjan Margin)

Andre Reymond, N'dri Koffi

The Cote d'Ivoire sedimentary basin is part of a typical transform passive margin developed along the West African coast from Liberia to Ghana. It straddles the coast-line and the sedimentary section expands dramatically South of the East-West trending Lagune Fault, with up to 10,000 metres of sediments from Aptian to Present in age. Albo-Aptian rift series, mainly continental clastics without evaporites, have accumulate progressively in a tilted semi-graben. The drift stage marks a widespread marine sedimentation organized in progradational sequences which blanket the Albian block fault topography of the continental break-up.

Reservoirs are mainly clastics and present in the section from Middle Albian to Maastrichtian. Sand bodies are associated with identified submarine fans, infill structures or channelized units deposited in a shelf or outer-shelf environment.

Trapping opportunities are due to block-faulting in the rift section, or gravity tectonics in the drift section, often combined with sand pinch-outs to constitute mixed structural-stratigraphic traps. Thick top-seal units formed by marine shales are widespread. Source-rocks have been shown to belong mainly to the rift series and they have been characterized in terms of geochemistry and maturation timing.

An efficient simulation model has been used to reconstruct the expulsion, migration and trapping of hydrocarbons along a selected North-South cross-section and to better define the Petroleum Systems.

AAPG Search and Discovery Article #90956©1995 AAPG International Convention and Exposition Meeting, Nice, France