Resumen de Foraminifera from the Palaeocene phosphate beds, Sokoto, Nigeria
John Haynes, Kenneth Nwabufo Ene
Boreholes from Sokoto reveal a low diversity foraminifera fauna of Tethyan aspect and Thanetian Age (Planktonic Foraminifera zones P4 and P5) indicating fluctuating marginal marine and lagoonal conditions during the deposition of the Lower and Middle part of the Dange Formation, normal marine conditions during deposition of the Upper Dange and warm, shallow, clear water marine conditions during deposition of the Kalambaina Limestone. The phosphatic horizons are interpreted to indicate stillstands when a combination of low oxygen and low alkalinity led to dissolution of shells and bone and concentration of phosphorites. Certain previously confused species are redescribed and their relations hips clarified, including Nummulitoides margaretae, Ornatanomalina hafeezi, Rotalia darbabyensis, Rotorbinella hensoni and Woodella pontica.
