African Surface

The African Surface or African Erosion Surface is a land surface formed by erosion covering large swathes of Africa.[1] The type area of the surface lies in South Africa where the surface was first identified as such by Lester Charles King in the mid-20th century.[2]

The term was coined by King for certain high surfaces in Southern Africa. Over the years he redefined it various times leaving some confusion not on its reality but on the matter of its precise meaning and extent.[2][3] Burke and Gunnell redefined it as a composite surface.[4] According to Guillocheau et al. (2008) the African Surface is made up by etchplains formed between 70 and 40 million years ago. In this sense the existence of parts of the African Surface at different elevations is the result of continental-scale warping due to endogenic forces.[4]

In Central Africa the African Surface can be found in uplifted position in several domes and elongated bulges between these domes and also in downwarped basins. The domes include the East African, Ethiopian, Cameroon and Angola. The Central African Atlantic Swell and the Central African Rise. Subdued regions include the Congo Basin where the African Surface lies about 300 m a.s.l. and the Turkana Gap.[4] In the interior of Western Africa the so-called Bauxitic Surface has been identified as equivalent to the African Surface.[5]

See also

References

  1. Burke & Gunnell 2008, pp. 6–7.
  2. Burke & Gunnell 2008, pp. 13–14.
  3. Burke & Gunnell 2008, pp. 15-16.
  4. Guillocheau, François; Simon, Brendon; Baby, Guillaume; Bessin, Paul; Robin, Cécile; Dauteuil, Olivier (2017). "Planation surfaces as a record of mantle dynamics: The case example of Africa" (PDF). Gondwana Research. 53: 82–98. doi:10.1016/j.gr.2017.05.015.
  5. Beauvais, A.; Ruffet, G.; Henócque, O.; Colin, F. (2008). "Chemical and physical erosion rhythms of the West African Cenozoic morphogenesis: The 39Ar-40Ar dating of supergene K-Mn oxides" (PDF). Journal of Geophysical Research. 113 (113): F04007. doi:10.1029/2008jf000996.
Bibliography
  • Burke, Kevin; Gunnell, Yanni (2008). The African Erosion Surface: A Continental-Scale Synthesis of Geomorphology, Tectonics, and Environmental Change over the Past 180 Million Years. The Geological Society of America. ISBN 978-0-8137-1201-7.


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