Cenozoic Geology of the Southern Cape Coastal Plain, Particularly the area between the Kafferkuils and Gouritz Estuaries

A marine peneplain truncates Cape Supergroup and Enon Formation sediments between the Kafferkuils and Gouritz Estuaries and is overlain by the Bredasdorp Formation. Unconsolidated iron-stained, quartzose sand of the Jongensfontein Silica Sand Member sporadically underlies younger calcarenites. The transgressional Kafferkuils Shelly Gravel Member underlies the well-cemented regressional Canca Calcarenite Member which is up to 300 m thick and has an outcrop 12 km wide. The lithological difference between the Jongensfontein and Canca Members probably reflects climatic deterioration from the Palaeogene to the Neogene. The outcrop of the Late Pleistocene transgressional Velddrif and regressional Langebaan Members which form semi-consolidated cliffs at Rooikrans, east of Still Bay, is only 60 m thick and only about 0,5 km wide. The major coast-parallel, closed depressions of Canca se Leegte and Grootkloof, NE of Still Bay, are karst landforms called poljes. The Recent Witzand Member consists of the modern beaches and dunes.