Today I revisited the site which I first described in 1963, very close to the old lifeboat station at Cei-bach, Poppit -- at the mouth of the Teifi estuary. Grid ref. SN 14355 49124.
Not a lot has changed! The raised beach deposits, here a little over 1m thick, are still beautifully displayed, cemented by iron oxide and manganese oxide precipitates. But note that the three large angular boulders that were resting on the beach materials in 1963 have now gone crashing down onto the beach below, and it looks to me as if the whole face here (including the rock face) has retreated by maybe 50 cms, as a result of ongoing coastal erosion by storm waves at times of high tide.
This is a classic example of an unconformity, with the tilted Ordovician shales and mudstones planed across by a beautiful wave-cut platform and with pseudo-stratified raised beach cobbles and gravels resting on it more or less horizontally.
The platform mat be of composite age, but the raised beach is almost certainly Ipswichian in age -- around 100,000 - 70,000 years old.
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