Hydrocarbon resource potential of the Bornu basin northeastern Nigerian

Abstract

The separation of Africa from South America was accompanied by rifting and sinistral strike-slip movements that formed the Bornu Basin. The Bornu Basin form part of the West African Rift System. Geochemical analyse of samples from the Fika Shale shows that eighty percent of the samples have TOC values >0.5 wt%. Plots on the modified Van Krevelen diagram indicate organic matter that is predominantly Type III kerogen. A corresponding plot on the HI–Tmax diagram indicates an entirely gas generative potential for the source rocks. In the Bornu Basin which belongs to the West African Rift Subsystem (WARS) two potential petroleum systems are suggested. “Lower Cretaceous Petroleum System” – is the phase 1 synrift sediments made up of sandstones with an extensive system of lacustrine deposits developed during Barremian to Albian time. “Upper Cretaceous Petroleum System” – is the phase II rift sediments in the Bornu Basin which comprise mainly shallow marine to paralic shales,
deltaic to tidal flat sandstones and minor carbonates. TOC values range generally from 0.23 wt. % to 1.13 wt. % with an average of 0.74 wt. % for the Fika Shale.