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HIGH-LEVEL GEAVELS OF THE CAPE AND THE 

 PROBLEM OF THE KARROO GOLD. 



By E. H. L. Schwarz, A.R.C.S., F.G.S. 



(Read January 27, 1904.) 



Plates IL-V. 



The high-level gravels of South Africa have attracted a good deal' 

 of attention for some considerable time owing to the peculiar position 

 they occupy. They are found capping the flat-topped hills all over 

 the southern coast-regions of the Colony — at one time as a flinty 

 quartzite, when they have been mistaken for lava-flows ; at another 

 as thick beds of gravel- and boulder-beds perched many hundreds of 

 feet above the present levels of the rivers, when they have been 

 mistaken for the Enon Conglomerate, a member of the Uitenhage 

 Series of Jurassic age. 



They were first studied by Mr. Rogers and myself along the 

 seaward face of the great coast-ranges, especially in Caledon, Swel- 

 lendam, and Riversdale, and later, in the extreme east, in Komgha. 

 and Kentani. For some time it was not clear whether the gravels 

 here were old sea-beaches, and that the level flats which they must, 

 have originally covered were not surf-cut terraces. As a matter of 

 fact the sea is at the present time cutting ledges along the coast, 

 which at low tide are exposed and continue the rocky land- surface 

 for a considerable distance out to sea ; east of Cape Agulhas, as far 

 as the Pondoland shore, these surf-cut terraces occur repeatedly, and 

 form the home of the oyster, the octopus, the ollycrock, and other- 

 sea delicacies. The gravels, however, have more the appearance of 

 river-borne material, and the fine sands that of river-sand, and the 

 question has been practically settled by the discovery of the fruits of 

 Cham — a typical fresh-water weed embedded in the hardened sands, 

 in Komgha. 



Inland the evidences of the gravels were not so abundant, though 

 Mr. Rogers and myself have recorded them as occurring in Ladi- 

 smith, Oudtshoorn, and Prince Albert. For the whole of the last 

 year I have been working on the watershed between the Gouritz 

 and Gamtoos river-systems, and have found the high-level gravels- 



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