This satellite image
(Figure 4)
is derived from SEASAT radar altimeter
measurements of the shape of the ocean surface.
The ocean surface reflects ocean bottom features such as
sea-mounts, ridges and fracture zones, related to the opening of
the Atlantic.
During the drifting apart of South America and Africa, two
transfer zones have affected offshore Suriname. The southernmost
transfer zone ceased to be active as can be seen from younger
sediments covering the fault trace (from Eocene onwards?). The
original location of the Demerara high can be seen on the
west-coast of Africa. It is important to note that the Demerara
high is not part of the African Achaean shield but part of the
rift system related to the Central Atlantic rift. The carbonates
penetrated by the Demerara well belonged to the carbonate fringe
along the northern African coast. The differential movements were
relayed by the northern transfer zone, and deepened further the
pull-part basin west of the Demerara High.