When I was over at Pwllderi, on the west side of the Pencaer Peninsula, the other day, I was suddenly struck by the extraordinary degree of ice moulding on the west-facing cliffs. Features like these would not be out of place on the coasts of Greenland or Antarctica, and they indicate just how powerful glacier ice can be when it is moving directly onto an old coastline (here from the NW) and is being forced to move upslope. So there must have been powerful abrasion, a great deal of entrainment of loose material, and a lot of shearing within the ice mass under compression.
Much of the coastline between Abermawr and St David's Head looks like this, and hillocks on the edge of the coastal plateau have also been smoothed off and rounded. I must do some more work on this, when I can find the time...... and one interesting question (one of many) is this: to what extent are these Devensian features, and to what extent are they inherited from earlier glacial episodes?
Strange how there is almost a symmetry between the photograph of Pwllderi and the rainbow ice image in the post below
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