Karoo an immense volume of rocks which was formed, geologically speaking, in a short period of time. Although almost the whole of the Great Karoo is situated on Karoo Supergroup rocks, the geological Karoo rocks extend over a very much larger area, both within South Africa and Lesotho, but also beyond its borders and onto other continents that formed part of Gondwana. The Karoo Supergroup was formed in vast inland basin starting 320 million years ago, at a time when the part of Gondwana which would eventually become Africa lay over the South Pole. Icebergs that had calved off the glaciers
Karoo desert ephemerals, spaced 50 cm or more apart, and becoming very sparse going northwards into Bushmanland and, from there, into the Kalahari Desert. The driest region of the Karoo, however, is its southwestern corner, between the Great Escarpment and the Cederberg-Skurweberg mountain ranges, called the Tankwa Karoo, which receives only 75 mm of rain annually. The eastern and north-eastern Karoo are often covered by large patches of grassland. The typical Karoo vegetation used to support large game, sometimes in vast herds. Today, sheep thrive on the xerophytes, though each sheep requires about 4 ha of grazing to sustain itself. The