Neogene/Quaternary boundary in the coastal basin of Togo

The end of the Neogene in the emerged part of the Togolese coastal basin corresponds to a sandy–argillaceous complex of continental appearance devoid of marine fauna and generally attributed to the “Continental terminal” in the neighboring West-African basins. Although the Neogene/Quaternary boundary is identified in this sandy–argillaceous complex in most of the boreholes studied and also in field sections, the lack of precise dating data especially paleontological evidence makes the definition of this boundary difficult. In the present state of knowledge, this boundary merges with an erosional paleosurface which coincides with the erosional discordance that separates the two units composing the sandy–argillaceous complex of the “Continental terminal” in this basin. The two units are the Kpogame pebble bearing formation which corresponds to “Continental terminal sensu stricto” (upper Miocene–Pliocene) and the “Formation de la Terre de barre” of Quaternary age. Future investigations will allow a more accurate determination of the Neogene/Quaternary boundary in this basin.