Geography of South Africa and Lowveld is the southern basin of the Kalahari Desert, which borders Namibia and Botswana at an elevation of 600 meters to 900 meters. The western section of South Africa on the inland side of the Cape Fold Mountains is dominated by the Great Karoo, a semi-desert region that is divided by the Great Escarpment into the Upper Karoo (at an elevation of 1100–1600 m) and the Lower Karoo (at an elevation of 600–800 m). Separated from the Great Karoo by the Swartberg mountain range is the Little Karoo. In the southwest, running parallel to the coastline, the mountains of
Karoo Group (i.e. the oldest layer of the Cape Supergroup). The valley floor is covered, in the main, by the next (younger) layer of the Supergroup, namely the much softer Bokkeveld shales. The dolerite of the Great Karoo did not penetrate these rocks, so Karoo Koppies are not seen in the Little Karoo. The Little Karoo contains two other geological features that give the landscape a special character. During the erosion of the African interior following the bulging of the continent during the massive lava outpourings that ended the Karoo sedimentation 180 million years ago, some of the eroded material was