Geological overview of the Angola–Congo margin, the Congo deep-sea fan and its submarine valleys

Bruno Savoye (1) , Nathalie Babonneau (2, 3) , Bernard Dennielou (1) , Martine Bez (4)

1 LGS - Laboratoire Géodynamique et enregistrement Sédimentaire
2 LDO - Domaines Océaniques
3 UEB - Université européenne de Bretagne - European University of Brittany
4 CSTJF - Centre scientifique et Technique Jean Feger

The Congo deep-sea fan is one of the largest fans in the world still affected by presently active turbidity currents. The present activity of deep-sea sedimentary processes is linked to the existence of a direct connection between the Congo River estuary and the Congo canyon head that allows relatively continuous sediment feeding of the deep-sea environment, in spite of a wide continental shelf (150 km). Because of this important activity in terms of sedimentary processes, the deep-sea environment of the Congo–Angola margin presents major interests concerning physical, chemical and biological studies near the seafloor. The main aim of this paper is to present the initial geological context of the BioZaire Program, showing a synthesis of the major results of the ZaïAngo Project including (1) the brief geological setting of the Congo–Angola margin, (2) the structure of the modern Congo deep-sea fan, (3) the sedimentary architecture of the recent Congo turbidite system (from the canyon to the distal lobes) and (4) the recent and present turbidite sedimentation. In order to provide useful information and advice relevant to biological and geochemical studies across the Congo sedimentary system, this article is particularly focused on the present sedimentary processes and the present activity of turbidity current along the Congo canyon and channel.

Keywords: Congo–Angola margin; Congo channel; Sedimentary deposits; Turbidite

Domains: Geomorphology

Bruno Savoye, Nathalie Babonneau, Bernard Dennielou, Martine Bez. Geological overview of the Angola–Congo margin, the Congo deep-sea fan and its submarine valleys. Deep Sea Research Part II: Topical Studies in Oceanography, 2009, 56 (23), pp.2169-2182. ⟨10.1016/j.dsr2.2009.04.001⟩. ⟨insu-00429479⟩