What is going on with the announced billions of BOEs offshore Namibia? Short answer: only about 150 million years of change after the great global Ice Age, which was 300 million years ago. Maybe not all global warming has been “bad.”
The ice that once covered the entire planet is attributed to have carved a network of fiords 300 million years ago according to NASA, Fig. 1. Alpine “valleys” could become pathways for sediments loaded with fossil carbon debris. That ice melted without the help of man, but the original shapes of the valleys appear to have remained down to the shoreline to continue somewhat subsea. How does NASA know? Check it out.
Ever since topographers around 1650 AD compared maps of South America (Joannes de Laet, 1630) to maps of Africa (Abraham Ortelius, Antwerp, 1570), there has been, or was, a constant argument about Continental Drift vs. something else. Eugeosynclines and mountain building moved to the background when Plate Tectonics moved into the forefront of geophysical thinking, based on thermodynamics, seismicity, and ancient maps.1 Sorry, geologists were reluctant to reprint their textbooks dragging their feet up until acclaimed by the AAPG.2
Once liberated or rechanneled imaginations went wide lens, early work concentrated on diamonds in Australia, compared to paleo South Africa. Then, a few bright souls concluded that southern Africa and very southern South America were either too far from paleo sources of fossil carbons OR, the continents broke apart before bitumen generation. Oil co. experts contended that at least The Malvinas/Falklands moved faster (a vector theory) in the break-apart of their northern adjacent masses and missed the carbon events altogether. Then, chance rewarded braver souls, who explored and found oil in southern Brazil offshore, down to Comodoro Rivadavia, Argentina. The maps came back out of the drawer. Interactive digital maps today make that adventure easier, more believable, educational, and fun (https://dinosaurpictures.org/ancient-earth#120).
Further seismic results. Seismic service companies once ventured a few regional 2D lines in the 1970s. They now offer comprehensive 3D and have ships ready for more offshore exploration along the western shores of very southern Africa, Fig. 2. While geologic interpretations are only in the early stages of understanding, there now exist reasons to accept that at least hundreds of vertical feet of source rock and reservoirs are present above the continental breakup unconformity. Probably, there could be a lot more than that.
As with all post-break-up areas, subsidence continues. Deposition builds until geo periods of sediments containing bitumen form in amounts that can generate hydrocarbons. Further sedimentation and subsidence supply cooking heat and hydrodynamic potential. Opportunity is available for moderate risk exploration of structural and stratigraphic traps that are both ancient and have recently been created. Traps would focus on deepwater turbidites, maybe some sub-salt structure similar to the features to the north in Angola, and even on some Gulf of Mexico-style grow faults. The area does not quite look like Agbomi.
Plenty more to come. The takeaway? Namibia has over 300 million years in forming super geo features. The largest beach version of a desert is over 1600 km (994 mi) of the Namib that follows a 50-to-160 km (31-to-99-mi) wide strip along the South Atlantic coast. The large Fish River Canyon, 160 km (99-mi) long and about 550 m (1,804 ft) deep, can be found with metamorphic rocks and inclusions beyond wonder. The canyon began forming during the Karoo Ice Age, further opening with continental breakup. (https://www.mme.gov.na/files/publications/09c_Geology_brochure.pdf). Exploration with seismic is only about 30 years old. You still have some time for a safari, Fig. 3. WO
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WJHTEXAS@AOL.COM / WILLIAM (BILL) HEAD is a technologist with over 40 years of experience in U.S. and international exploration.