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 been washed away by denudation. Now the continent rose, and in doing so the rift valleys caused slips of the earth's crust to sink into fault pits arranged in linear series. The mountains, towering once more, caused great precipitation; rivers coursed over the plains, scouring off all the newly formed and still loosely compacted shales, sands, and gravels, and all would have disappeared had not some of them been dropped into the fault pits, where the rims of harder rocks protected them from being carried away. It is in these fault pits alone, therefore, that we now find the Uitenhage Beds. They formed originally a continuous deposit certainly from Uitenhage to Worcester, a distance of 200 ml., but they probably extended all over the east, and the Emboyti Conglomerates on the Pondoland coast east of St. John's are probably a remnant. They certainly were formed in the north of the mountain ranges, filling in the space between the folded mountains and the escarpment of the Nieuwveld, Cambdeboo, and other mountains, which had already been cut, but all trace of these inland Uitenhage Beds has disappeared.

The Uitenhage Beds are lower Cretaceous; the freshwater fossils are Wealden, and the marine Neocornian, the two terms indicating different facies of contemporary beds. The most interesting fossils in the marine series are the Ammonites and Trigonias, which occur very plentifully; one Plesiosaurus has been discovered, at Redhouse.

The Pondoland Formation

These Upper Cretaceous beds have been also called the Umzamba Beds and the Izinhluzabalungu Beds. They occur just on the Cape Colony side of the Umtamvuna