Geochronological arguments for a close relationship between surficial formation profiles and environmental crisis (c. 3000-2000 BP) in Gabon (Central Africa).

Denis Thiéblemont (1) , Christine Fléhoc (1) , Michel Ebang Obiang (2) , Christophe Rigollet (1) , Jean-Pierre Prian (1) , François Prognon (1)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
2 DGMG - Direction Générale des Mines et de la Géologie

We present new 14C data on charcoal fragments recovered from the lower (coarse-grained Stone Line) and upper (fine-grained Cover Horizon) portions of surficial formation profiles in Gabon. These data and others compiled from the literature enable a reconstruction of the Upper Holocene geological regional history of Gabon. The connection between the geological events recorded in the surficial formations and the upper Holocene environmental crisis is discussed and a scenario connecting geological events with climatic and environmental changes is proposed. Such a scenario suggests that following the climatic crisis, the reconstitution of soils by aeolian sedimentation could have been an important factor of Bantu expansion.

Mots clés: Central Africa; aeolian deposit; Quaternary; Holocene; surficial formations; climatic crisis; Bantu expansion

Domaines: Sciences de la Terre

Denis Thiéblemont, Christine Fléhoc, Michel Ebang Obiang, Christophe Rigollet, Jean-Pierre Prian, et al.. Geochronological arguments for a close relationship between surficial formation profiles and environmental crisis (c. 3000-2000 BP) in Gabon (Central Africa).. Comptes Rendus Géoscience, 2013, 345 (7-8), pp.272-285. ⟨10.1016/j.crte.2013.06.002⟩. ⟨hal-00904029⟩