I've just done this new map of the proposed LGM (Last Glacial Maximum) limit on the isles of Scilly. The map (with grateful thanks) is from James Scourse 1991 and 1998. The solid black line is the limit as accepted by James and most other recent researchers. The dashed line, showing the extent of the Hell Bay Gravel, does not in my view have any significance. My ice limit for the Devensian, based upon observations in April 2016, is shown by the red line.
The biggest changes are the tongues of ice which I believe to have penetrated along the sounds between St Martin's and Tresco and Tresco and Bryher, and a much bigger lobe that pushed in from the west across St Mary's Road right up to the west coast of St Mary's. St Agnes was certainly affected by Devensian ice, but I am uncertain about Annet, Samson and the Eastern Isles. Maybe somebody else can gather evidence from those, over the coming summer season.........
It's interesting that the latest dating suggests that the maximum ice extent here was around 25,000 - 23,000 years ago -- earlier than previously supposed.
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