Stratigraphic analysis of high-resolution 2D seismic allow to clarify the tectonic and stratigraphic history of the WAB.

A three step tectonic and stratigraphic scenario is proposed based on the seismic interpretation and onshore correlations.

A first subsidence pulse controlled by extensional detachment is followed by a vertical subsidence marking a sag behavior.

We explain that the subsidence of the WAB was controlled by the load of the dipping subducting lithosphere.