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The Kaapvaal Craton (centred on the Limpopo Province in South Africa), along with the Pilbara Craton of Western Australia, are the only remaining areas of pristine 3.6–2.5 Ga (billion years ago) crust on Earth. Similarities of rock records from both these , especially of the overlying late Archean sequences, suggest that they were once part of the Vaalbara supercontinent.Zegers, T.E., de Wit, M.J., Dann, J. and White, S.H. (1998) "Vaalbara, Earth's oldest assembled continent? A combined, structural, geochronological, and palaeomagnetic test", Terra Nova, 10, 250–259.
The Kaapvaal Craton formed and stabilised between 3.7 and 2.6 Ga by the emplacement of major granite that thickened and stabilised the continental crust during the early stages of an Volcanic arc-related magmatism and sedimentation cycle. The craton is a mixture of early Archean (3.0–3.5 Ga) granite Greenstone belt and older tonalite (ca. 3.6–3.7 Ga), intruded by a variety of granitic (3.3–3.0 Ga). Subsequent evolution of the Kaapvaal Craton (3.0–2.7 Ga) is thought to be associated with continent–arc collision that caused an overlaying succession of basins filled with thick sequences of both volcanic and sedimentary rocks. This was then followed by episodic extension and when the Gaborone–Kanye and Ventersdorp sequences were developed. Early Archean crust is well exposed only on the east side of the craton and comprises a collage of subdomains and crustal blocks characterised by distinctive igneous rocks and deformations.
Late Archean metamorphism joined the Southern Marginal Zone of the Kaapvaal Craton to the Northern Marginal Zone of the Zimbabwe Craton approximately 2.8–2.5 Ga by the wide orogeny Limpopo Belt. The belt is an east-northeast trending zone of granulite facies that separates the granitoid-greenstone terranes of the Kaapvaal and Zimbabwe cratons.
There is no indication that the Neoarchean to early Paleoproterozoic succession on the craton were sourced from the 2.65–2.70 Ga orogenic event preserved in the Limpopo Metamorphic Complex. However, younger late-Paleoproterozoic red bed successions contain of this time interval as well as many ~2.0 Ga detrital zircons. This implies that the Limpopo Complex together with the Zimbabwe Craton only became attached to the Kaapvaal Craton at approximately 2.0 Ga during formation of the Magondi Mobile Belt which in turn sourced the voluminous late Paleoproterozoic red beds of southern Africa.Beukes, N.J., Dorland, H.C., Gutzmer, J., Evans, D.A.D. and Armstrong, R.A. (2004) "Timing and Provenance of Neoarchean-Paleoproterozoic Unconformity Bounded Sequences on the Kaapval Craton" , Geological Society of America Abstracts with Programs, 36 (5), 255. Evidence of the horizontal layering and riverine erosion can be found throughout the Waterberg Massif within the Limpopo Central Zone.
These rocks consisting mainly of granodiorites constitute the third magmatic event and occupy an area of batholithic dimensions extending across most of the southern portion of the dome. The southern and southeastern parts of the batholith consist mainly of medium-grained, homogeneous, grey granodiorites dated at 3121 +/- 5 Ma....The data, combined with that from other parts of the Kaapvaal craton, further supports the view that the evolution of the craton was long-lived and episodic, and that it grew by accretionary processes, becoming generally younger to the north and west of the ca. 3.5 Ga Barberton- Eswatini granite-greenstone terrane situated in the southeastern part of the craton."Poujol, M. and Anhaeusser, C.R. (2001) "The Johannesburg Dome, South Africa: new single zircon U-Pb isotopic evidence for early Archaean granite-greenstone development within the central Kaapvaal Craton", Precambrian Research, 108 (1–2), 139–157, .
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