Paleocene stratigraphic revision and paleoenvironment of the southern coastline of the Dakar peninsula (Western Senegal)

摘要

Biostratigraphic study of outcrops from South of Dakar confirmed the Lower (Danian) to Middle Paleocene age of the "Formation des Madeleines" and the attribution for the first time of an Upper Paleocene age (Thanetian) to the "Formation de l'Hopital" with the aid of planctonic foraminifers. Microfaunistic (foraminifera, ostracoda) and sedimentologic data (Zoophycos bioturbations) confirmed a mesobathyal to epibathyal environment during the Danian, while the Thanetian deposits are inner shelf to littoral types. This paleobathymetric evolution is related to the uplift of the hoist of Dakar and the decline of sea level at the end of Paleocene.