Tectonic style and mechanism of early proterozoic successor basin development, Southern Africa

Kaapvaal craton: Changing first- and second-order controls on sea level from c. 3.0 Ga to 2.0 Ga

“…Ebinger and Sleep, 1998), with sedimentation occurring in the quiescent intervals between such events . Clendenin et al (1988) have noted that many of the Platberg grabens exceed 200 km width, which is c. 4-6 times greater than that commonly observed for rift basins (e.g., Brun and Choukroune, 1983). This again, supports a plume-driven upper crustal tectonic regime, and large rifts would have developed a significant (inverted) sublithospheric topography to trap ponded magma beneath the individual Platberg basins (cf., Sleep, 1996Sleep, , 1997.…”

“…An extensional block-faulting model has been espoused by many (Button et al, 1981;Tankard et al, 1982;Winter, 1986;Charlesworth et al, 1986;McCarthy et al, 1987;Colliston and Reimold, 1987); Clendenin et al (1988) suggested a successor basin model for the Witwatersrand, Ventersdorp and Transvaal basins, and that aesthenospheric upwelling influenced the general extensional tectonic setting. An impactogenal rifting model, related to the Limpopo belt collision, discussed above, has also enjoyed significant support (e.g., Robb et al, 1991).…”

New U–Pb SHRIMP zircon age for the Schurwedraai alkali granite: Implications for pre-impact development of the Vredefort Dome and extent of Bushveld magmatism, South Africa

“…5. Deposition of the Transvaal Supergroup from 2.6-2.25 Ga (Armstrong et al, 1991;Walraven, 1997;Clendennin et al, 1988). 4.…”

“…Deposition of the Transvaal Supergroup began at approximately 2.6 Ga, when a shallow sea covered much of the Kaapvaal Craton. Cessation of deposition within the Transvaal Supergroup occurred at approximately 2.25 Ga (Walraven, 1997;Clendennin et al, 1988). The Bushveld magmatic event initiated at approximately 2.06 Ga (Walraven, 1997) with the extrusion of the dominantly silicic volcanic rocks of the Rooiberg Group, followed by the intrusion of mafic and ultramafic magmas (Rustenburg Layered Suite, Fig.…”

“…The collar rocks comprise a series of unconformitybounded sedimentary and volcanic sequences deposited between 3.07 and 2.25 Ga in a succession of basins on the Kaapvaal Craton (Clendennin et al, 1988). They are now overturned and young away from the core of the dome structure.…”