Precise microbeam dating defines three Archaean granitoid suites at the southwestern margin of the Kaapvaal Craton

South of the Marydale High a narrow strip of Draghoender-type Granite extends to Franzenhof where it is exposed in a Dwyka glacial outwash surface and is dated at 2931 ± 9 Ma. The southernmost exposures of granite are windows in the Dwyka group about 130 km southeast of Marydale on both sides of the Doornberg Fault. The 2905 ± 7 Ma Maritzdam Granite which is basement to Ventersdorp Supergroup volcanic rocks at Kuip is monzogranitic and corresponds to the Skalkseput type. On the southwest side of the Doornberg Fault the 2907 ± 4 Ma Welgevonden Granite underlies Marydale Group volcanic rocks, showing that the Kaapvaal basement extends across the fault.