- Karoo Supergroup
The Karoo Supergroup is the largest stratigraphic unit in Southern
Africa , covering almost two thirds of the present land surface, including centralCape Province , almost all ofOrange Free State , western Natal, much of south-eastTransvaal ,Zambia ,Zimbabwe andMalawi .Its strata, mostly
shale s andsandstone s (Hamilton & Finlay 1928), record an almost continuous sequence of marine glacial to terrestrial deposition from the Late Carboniferous to theEarly Jurassic , a period of about a hundred million years. These accumulated in aretroarc foreland basin called theKaroo Basin. Its sediments attain a maximum cumulative thickness of 12 km, with the overlying basaltic lavas (the Drakensberg Group) at least 1.4 km thick.(Adelmann and Fiedler 1996).Fossils include
plant s (both macro-fossils andpollen ), rareinvertebrate s andfish , common and diversetetrapod s (mostlytherapsid reptiles, temnospondyl amphibians, and in the upper stratadinosaur s), andichnofossil s. Theirbiostratigraphy has been used as the international standard for global correlation ofPermian toJurassic nonmarine strata. (Hancox & Rubidge, 1997)The Karoo Supergroup is divided into the following strata (from oldest to youngest):
*
Dwyka Group (glacial marine)
*Ecca Group
*Beaufort Group (terrestrial)
*Stormberg Group (including basalts)ee also
*
Waterberg References
* Adelmann, D. and Fiedler, K., (1996), [http://www.adelmann.geosciences.de/doc/Karoo-Sedimentoloy.html Sedimentary development of the Upper Ecca and Lower Beaufort Groups (Karoo Supergroup) in the Laingsburg subbasin (SW Karoo Basin, Cape Province/South Africa)] , "Schriftenreihe der Deutschen Geologischen Gesellschaft", 1: 88-89, Bonn
* Hamilton, G.N.G. and Finlay, J.G. (1928), "Outline of Geology for South African Students", Central News Agency Ltd, Johannesburg
* Hancox, P.J. & Rubidge, B.S. (1997), The role of fossils in interpreting the development of the Karoo basin. "Palaeontol. Afr." 33: 41-54.
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