Structural and stratigraphic variability of the African margin of the Equatorial Atlantic
Résumé
The Transform Source to Sink Project (TS2P) objective is to link the
evolution of the sedimentary basins of the African margin of the Equatorial
Atlantic and their source areas developing on West African Craton.
The Equatorial Atlantic segment varies from a normal passive margin in
the North-West (Guinea), to an oblique margin (Sierra Leone and Liberia)
and to a transform margin (Ivory Coast and Ghana). This evolution
is associated with variation in the margin width, continental relief, drainage
organization and subsidence/accumulation patterns that we analyzed
using seismic data and onshore geology.
We compare syn-rift geometry and long-term stratigraphic history of
each of these segments. Preliminary results in Sierra Leone and Liberia
segment show that syn-rift geometries (Lower Cretaceous) are increasingly
influenced by transform faults toward the South-East and the
immediate post-rift Upper Cretaceous wedge is associated with a marine
transgression and reactivation of transform faults. These results will
then be used to estimate sediment budgets and integrated in a sourceto-
sink analysis where onshore denudation will be estimated by low-
Temperature thermochronology