Page:South African Geology - Schwarz - 1912.djvu/204

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SOUTH AFRICAN GEOLOGY

The Table Mountain Sandstone is quite typical in the south, it is a coarse false-bedded sandstone, weathering greyish white, and usually lies fairly flat. The red Waterberg sandstones in the north are similarly laid, and the unconformity that should exist between the two sandstones has not yet been discovered. These two formations formed the surface of the land bordering the Karroo lake on the eastern side, and now form the basis on which the Dwyka Conglomerate rests. No glacial pavements have been found except in the Vryheid and Utrecht divisions, where the conglomerate rests directly on the Swaziland Beds and granite.

The Cretaceous beds of Zululand consist of gritty sandstones more or less calcareous, with clays and marls, containing corals, gasteropods, and a vast number of species of Ammonites and Nautilus. The beds are Cenomanian to Lower Turonian, and are therefore a little older than the Pondoland Cretaceous beds. Similar beds have been found in Sofala, German East Africa, and Madagascar.

Along the littoral in Zululand there are exposed at very low tide a series of beds, the bottommost of which consists of shales containing the bones of extinct forms of rhinoceros, elephas, and large antelopes. Over this is a series of shales with a few scattered bones and crustacean and fish remains. Above this is a thin layer of foraminiferal sand, and then a foot or so of shales containing Tertiary mollusca. On top there are some 100 ft. of false-bedded sands of various colours, covered by the Recent sand dunes.