Page:South African Geology - Schwarz - 1912.djvu/203

 territory, which is a sunken area covered with Upper cetaceous deposits.

NATAL

The Province of Natal consists primarily of two portions: an elevated shelf along the coast made up of granite and Swaziland Beds, covered with Table Mountain Sandstone on the south, and with reddish sandstones and arkoses referable to the Waterberg System on the north, the whole further covered with Dwyka Conglomerate. The inland portion is the mountainous region commencing with the Dwyka Conglomerate, and followed by a reduced thickness of Karroo sediments with the coal measures, up to the Stormberg Formation, and finally, on the eastern border rising to the lavas of the Drakensberg. In Zululand there is the end portion of the sunken area covered with Cretaceous deposits which we saw in Portuguese East Africa, which includes St. Lucia Bay, and terminates at Port Durnford. South of the latter point the coast is bordered by the Great Fault, and only just over the border in Cape Colony do the Upper Cretaceous deposits appear at the Umzamba River. The Swaziland Beds are exposed along the deep gorges which the Rivers Umzimkulu, Umkoinaas, Umgeni, Umvoti, and Tugela have cut through the overlying Table Mountain Sandstone or Red Sandstone respectively. Along the Umzimkulu, there are beds of limestone which have been invaded by the granite, as in Worcester, Cape Colony, but on a very large scale. The rock resulting from the contact is a coarsely crystalline white marble with many lime and magnesium silicates formed as a result of the invasion of the igneous mass.