Many thanks to Hugh for publishing this wonderful photo on his Preseli 360 Facebook page. It's one of the best photos I have seen which portrays the landscape on the north face of Preseli -- with the craggy tor of Carn Goedog in the centre of the photo.
This north flank was perfectly placed for the accumulation substantial thicknesses of snow and firn -- and maybe glacier ice -- during the Early and Middle Devensian -- prior to the arrive of the Irish Sea Ice at the time of the LGM. This might have been a snowy tundra wilderness for the best part of 70,0-00 years.
To the left, on the rolling plateau ridge, I am now more than ever convinced that a Preseli ice cap waxed and waned several times as the climate oscillated between interstadial and continuous permafrost conditions. There is local till on these slopes, and across the moor to the right of the photo there are abundant spotted dolerite boulders that must have been carried NORTHWARDS by glacier ice. There is a lot of till on Brynberian Moor as well. On the slopes there are also traces of meltwater channels and morainic accumulations, and there are many examples of ice moulded forms on the tors -- I am still trying to work out how old these features are, and how they were formed.........
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