How much do we know about Stonehenge? Less than we think. And what has Stonehenge got to do with the Ice Age? More than we might think. This blog is mostly devoted to the problems of where the Stonehenge bluestones came from, and how they got from their source areas to the monument. Now and then I will muse on related Stonehenge topics which have an Ice Age dimension...
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Wednesday, 5 March 2014
Westdale Bay -- close to the Devensian ice edge?
These 3 photos are from Westdale Bay, not far from the mouth of Milford Haven and quite close to the village of Dale. The deposits there are seriously confusing.
If you look at the top photo, taken at least 50 years ago when I was young and innocent, you can see clearly the banded nature of the sediments high in the sequence -- suggesting water deposition or maybe flowage of saturated sediments very close to an ice edge.
But the ice edge at the maximum extent of the Devensian wasn't here -- it was, according to my interpretation of the evidence, further to the east across the peninsula, where a wonderful kame terrace was once exposed in all its glory when gravel working was going on there. This was at Mullock Bridge. That having been said, at the base of the sequence there is certainly an excellent exposure of Irish Sea till, coloured reddish because the rocks hereabouts are ORS. This layer is shown in the middle photo.
The bigger problem is associated with the lower photo, showing a deposit from higher in the sequence -- I thought at first that it showed a finer-grained till, but now I'm not sure. It looks more like a soliflucted or rearranged till, composed mostly of rather angular fragments of locally derived sandstones.
Must get back there one day and have a look...... so little time, and so much to do...
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