The Angolan margin is the type area for raft tectonics. New seismic data reveal the contractional buffer for this thin-skinned extension. A composite section from the Lower Congo Basin and Kwanza Basin illustrates a complex history of superposed deformation caused by (1) progradation of the margin and (2) episodic Tertiary epeirogenic uplift. Late Cretaceous tectonic movement was driven by a gentle slope created by thermal subsidence. Extensional rafting took place updip, contractional thrusting and buckling downdip. Some distal folds were possibly unroofed to form massive salt walls.

Oligocene deformation was triggered by kinking of the Atlantic Hinge Zone as the shelf and coastal plain rose by 2 or 3 km. Uplift stripped Paleogene cover off the shelf, provided space for Miocene progradation, and steepened the continental slope, triggering more extension and buckling.

In Neogene time a subsalt half-graben was inverted, creating keystone faults that may have controlled the Congo Canyon.

A thrust duplex of seaward-displaced salt jacked up the former abyssal plain, creating a plateau of salt 3 4 km thick on the present lower slope. The Angola Escarpment may be the toe of the the Angola thrust nappe, in which a largely Cretaceous roof of gently buckled strata may have been transported above the salt duplex as far as 1-20 km.

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