Introduction
The Ventersdorp Supergroup is dominated by andesitic lavas interlayerd with subordinate agglomerate and conglomerate tuff units. The Ventersdorp Supergroup uncomformably overlies the Witwatersrand Supergroup. This Group is very thick, more than 4500m. Outcrops mostly occur in the Northern Cape and Western Transvaal. The lower Kliprivierberg Group is mafic lava and tuff. The upper Platberg Group is conglomerates and breccia on top of Kliprivierberg, with intermediate and felsic lava higher, with quartzite, shale and siltstone layers in between.
Geohydrology
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