石油および環境バイオテクノロジージャーナル

概要

A Review of the Geology of the Rio Del Rey Basin, Offshore Cameroon

Boris B Bate, Maduka Bertram Ozumba, Edwin Ayuk Ndip and Dorcas S Eyinla

A review of the tectonic evolution, stratigraphic and structural framework, petroleum systems and hydrocarbon potential of the offshore portion of Rio Del Rey (RDR) Basin in Cameroon is presented in this paper. The RDR basin is a passive margin basin present in the Gulf of Guinea and it is located southeast of Niger Delta over an area of about 7,000 km² offshore. Its stratigraphic components, like those of Niger Delta, comprise of a diachronous succession of prodelta shales (Akata Formation), overlain by delta front sands and shales (Agbada Formation), in turn, overlain by fluvial sands (Benin Formation). The age of this basin ranges from Eocene to Recent and it consists of four structural provinces namely; the growth fault province in the north, the Cretaceous Onshore province in the southeast, the Shale Ridge province in the southwest, and the Delta Toe-thrust in the south-central region. The RDR Basin features three stages of tectonic development: Pre-rift phase (Late Proterozoic to Late Jurassic); Syn-rift phase (Late Jurassic to Early Cretaceous) and Post-rift phase (Late Cretaceous to Holocene). It presently stands out as the major contributor of the petroleum in the country.