The delta is bounded on the east
by the Cameroon Volcanic Zone, and on the west by
the offshore Dahomey Basin and the Nigerian
crystalline massifs; to the north it feathers out onto
Cretaceous rift sediments of the Benue Trough; to
the south it progrades into deep-water above Albian
oceanic crust. The oceanic basement surface dips
landwards and is smooth, except at the apex of the
delta, where a high relief block, associated with the
Charcot Fracture Zone, has affected toe thrusting of
the delta sediments. Sedimentation in the SE
sector of the deep-water was constrained between
the rigid elements of the Charcot high and the
Cameroon Volcanic Zone (Muhuri et al., 2004). The
thickest sediments lie under the apex of the modern
delta and may exceed 30,000 ft.