A reappraisal of salviniaceous fossils and its implication on the age and depositional environment of Nkporo Shale of Calabar Flank, Nigeria

Abstract

Integrated floral and faunal (foraminiferal) data permit a precise interpretation of the age and depositional environment of the outcrop section exposed along the Calabar-Itu at 42.5 km point. The outcrop section belongs to the Nkporo Shale of the Calabar Flank from which Ariadnaesporiles nigeriensis Obebode & Skarby was reported and described. The results obtained indicate an Early Maastrichtian age and deposition in a brackish swamp environment. the biostratigraphic and environmental significance of Salviniaceous fossils have been consequently assessed.