Review of the geology of mamfe sedimentary basin, SW Cameroon, Central Africa

Abstract

This paper presents a review of the tectonic evolution, stratigraphy, paleontology, hydrogeological aspects and economic geology of the Mamfe basin. The main structures are basement –involved and detached fault and simple symmetrical fold with NE-SW trend. The basin measures 130 km in length and the widest part is about 60 km and a maximum area of 3200 km2. The maximum sediment thickness is estimated at 4–7 km and the sedimentary infill includes a lower alluvial fans to fluvial basal conglomerate and conglomeratic sandstone, a middle alternating (cyclic) aqueous to anoxic deep lake bottom black shale and limestone unit and an upper fluvial to transitional deltaic nearshore conglomeratic sandstone unit. The Ostracod fauna from the shale are very similar to the coeval fauna from adjacent Benue trough. The reported fauna have no biostratigraphic significance because of their uncertain age, low diversity, and cosmopolitan distribution during the early Cretaceous. Over 30 salt springs exist across the Mamfe basin with the most concentrated yielding 79 g/L of high quality halite. Several mineral indices (including diamond) have been identify and the geological condition favour the occurrences of hydrocarbon.