A fine photo from Casey Cilshafe showing the exposed peat beds exposed as a result of the lowering and re-configuration of the pebble storm beach. As we can see, the surface has been modified by rills -- partly because of sea water running downslope when the tide is high, and partly because impounded fresh water from behind the storm beach is infiltrating the beach and flowing down towards the sandy beach (which is submerged in this photo). This exposure has been partly re-covered by pebbles in the past few days.
Stream water flowing across an exposure of the peat beds -- this is not pure peat but "peaty mud" containing abundant plant remains and occasional tree roots and fallen branches.
Remains of a tree stump and root system on the surface of the peat bed.
A sharp contact between an overlying peat layer (up to 10cm think nowadays -- it may well have been much thicker prior to millennia of erosion beneath the storm beach) and light grey / bluish clay with sand and silt. This does not appear to be classic Irish Sea Till -- but it is probably part of the glacial sequence.
Vertical section showing how sharp the contact is between the dark brown peat layer and the underlying grey clay.
About 10 m away from the peat bed exposures, there is an exposure of Irish Sea till, also showing through the pebble beach. This confirms how thin and ephemeral the storm beach actually is. Near the trowel we see a disintegrated lump of lignite. Shell fragments are also present, as in the main exposure of Irish Sea till in the northern drift cliff.
Some previous posts on the Abermawr submerged forest and peat beds:
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