Page 12 - KBHA BULLETIN 2

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calcareous deposits deposited, we know from the marine micro-fossils in them, under the sea

and partly on, or near, a beach. These deposits, in which no fossils occur, created a large bay.

Much farther south, at Milnerton beach, marine fossils of this age or possibly the end of the
Miocene are washed up after storms. These include whales, sharks and some terrestrial

elements that include rhino, possible ancestral elephants and antelopes. Similarly, in early
Pliocene deposits at the Koeberg Power Station, excavations 26 m below present sea level

revealed marine molluscs, whales, sharks and other fish and seabirds. These included three

extinct species of penguin, petrels and shearwaters, Cape, Crowned and other cormorants,
and a gannet. A francolin was the only terrestrial species found, although isolated pieces of

antelope have been reported. An exposure at Ysterplaat also yielded remains of extinct

penguins.

Five million years ago False Bay and its surrounds would have been significantly different.
Many of the Langebaanweg animals would have lived in the area where suitable habitat

existed. The Fish Hoek/Noordhoek Valley would have been breached. Glencairn and
Clovelly would have been narrow, steep-sided inlets. The Cape Flats would also have been

breached leaving much of the Cape Peninsula Mountain Chain as an island. (Fig. 1.4.)

Middle to Late Pliocene and Early Pleistocene Epochs (4 – 1,7 mya to 0,75 mya)

Later, between about 3 to 4 mya, the sea-level dropped again and most of the earlier Pliocene

sediments were washed out to sea by the rivers as they cut valleys over the newly-exposed
land; the coastal barrier, however, protected the underlying earlier deposits at Langebaanweg,

thereby preserving the phosphates in them and the unique fossil remains which were revealed

during mining.

Subsequent fossil assemblages are small by comparison, and our information about later

times is limited. They include “carpets” of shells of landsnails and numerous tortoises above
the phosphate quarry which are thought to have been accumulated during the period of lower