Angola

Potential Source-Rocks

Rift-type Basins

Although, on most deep offshore seismic lines of the of SW Africa margin, the rift-type basins associated with the breakup of the lithosphere are not very visible, on this Canvas autotrace of a Cabinda offshore seismic line, the rift-type of basins, developed during the lengthening of the Gondwana small supercontinent (austral continent of the supercontinent Pangea) and capped by the breakup unconformity (picked in red color in this tentative interpretation) are easily recognized. It is in these sedimentary basins that are found the lacustrine shales that form the well known generating petroleum sub-system in Cabinda onshore and conventional offshore. The potential marine source-rocks, associated with the maximum flooding surface of the Cretaceous marine ingression (Cenomanian/Turonian) are, in these area immature, in spite of the the Tertiary uplift (truncation at the sea floor), which is quite evident on this tentative geological interpretation (the bottom of the salt and correlative salt-welds are , also, tilted seaward due to the uplift continent.