Many thanks to Ruth Crofts for these photos, taken at Abereiddi after one of the winter storms had exposed quite a large expanse of the submerged forest at Abereiddi.
These photos are important bcause they show a stratigraphy of three layers:
3. Peat bed incorporating tree roots and branches and other detrital debris
2. Purple clay layer which is clearly "churned"
1. Buff clay layer which contains many erratic clasts of all shapes and sizes
It is possible that the purple layer is the weathered "cap" of the layer below, but the churning is quite spectacular. In this situation we cannot be dealing with a violent liquified mud flow -- and the interpretation must be that this is a periglacial feature, created at a time of permafrost. In the lowest layer I think we are looking at a deposit of the Irish Sea till, similar to that of the Abermawr exposure some miles to the east.
So my interpretation here would be: Late Devensian glaciation and deposition of Irish Sea till >>> late glacial cold climate episode with permafrost and creation of involutions >>> Holocene temperate conditions with peat growth and climax woodland >>> sea level rise and inundation of the woodland and peat bed, probably within the past 5,000 years.
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