Geometry of the African margins of theEquatorial Atlantic

National audienceThe objective of the Transform Source to Sink Project (TS2P)is to link the dynamics of the erosion of theWest African Craton tothe offshore sedimentary basins of the African margin of the EquatorialAtlantic at geological time scales. This margin, alternatingtransform and oblique segments from Guinea to Nigeria, shows astrong structural variability in the margin width, continental geologyand relief, drainage networks and subsidence/accumulationpatterns. We analyzed this system combining onshore geologyand geomorphology as well as offshore sub-surface data. Syn-riftarchitectures (Early Cretaceous) are largely impacted by transformfaults that define sub-basins with contrasted width of crustal neckingzone (narrower in transform segments than in oblique/normalsegments). During the Late Cretaceous post-rift, sedimentarywedges record a transgression along the all margin. Proximal partsof the sedimentary wedge are preserved in basins developing onsegments with wide crustal necking zone while they were erodedaway in basins developing on narrow segments. As a difference, theCenozoic wedge is everywhere preserved across the whole widthof the margin