Maersk Viking Drillship, page-7

Since the Brulpadda discovery earlier this year AziNam said the result has turned the previous model on it's head for Southern Africa and the West coast. The well confirms Aptian source rock is extensive in the region and capable of filling world-class reservoirs

And from Envoi

In the Walvis basin and essentially totally undrilled Luderitz Basin though, there is now also clear evidence that many of the historic wells were drilled above the Upper Aptian Shale, which appears to be over pressured and could be acting as a seal. Equally interesting is the fact that the few wells drilled below the seal in the right parts of these and the Orange Basin to the south all found hydrocarbons where the wells encountered any reservoir. New wells that will test this concept will almost certainly result.

HTTP://www.frontierenergy.network/ceos-picks/2019/5/22/mike-lakin-managing-director-envoi-limited-at-the-africa-eampp-summit-london