Morainic ridges definining old glacier edges in the High Atlas (Photos: Philip Hughes)
Not many people realise that there have been many glaciers in the High Atlas Mountains of Morocco. Here's a man who knows rather a lot about them:
http://www.qpg.geog.cam.ac.uk/people/hughes/
There is now quite a substantial literature from Philip and assorted colleagues, and a chronology is being put together. It seems that there were small glaciers here in the Younger Dryas, in the highest areas (there are two peaks over 4,000 m) where snow accumulation was possible -- and snowfields and glaciers must have been much larger during the Devensian Glaciation. But it appears from cosmogenic dates that there may be some strange things going on here, and no precise synchronicity with NW Europe. Were there large ice caps in these mountains at some stages? The researchers think that is possible, since there are many troughs, cirques, roche moutonnees and glaciated pavements to be seen, but much more field evidence needs to be collected before the situation becomes clearer. All we know at present is that there are abundant moraines and traces of glacial action in at least 20 discrete areas through the High Atlas, and that the longest Devensian glaciers were up to 10 km long.
I made a mistake in a recent comment made to you Brian. Actually,it was Pro Colin Richards that found bluestones to the north-west of Stonehenge while I was there a few years ago.
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Tom.
Not that this has anything to do with Morocco -- but never mind...... So Prof Colin Richards also has evidence of bluestone fragments scattered about across the Stonehenge landscape? That doesn't surprise me -- there are assorted other mentions from geologists and archaeologists too. In the MPP et al Antiquity paper there is mention of a bluestone chunk UNDER the Avenue embankment -- meaning it must have been there before the embankment was built. There seems to be wholesale confusion just now, given that the 50 or so radiocarbon dates from Rhosyfelin tell us NOTHING about either quarrying or stone transport.
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