Local ice caps in the Auvergne, France

Two spectacular peaks on the flanks of a short steep trough which carried northwards flowing ice in the last glacial episode.  The photo was taken from a popular viewing point in a broad cirque -- at some stages this must have held its own small glacier which flowed between containing valley sides 

into the distance.

I have just had the pleasure of a week in the Auvergne in the company of old friends, seeing something of the spectacular landscape bathed in autumn colours.  

I had not previously known anything about the role of ice in shaping the landscape of the Massif Central, since most of the big landscape features (and many of the smaller ones) are related to a volcanic history stretching back many millions of years. There are 450 extinct volcanoes.There are basalts, lavas, ignimbrites and ash beds everywhere, with many volcanic plugs (such as Puy de Dome), ash cones, circular volcanic lakes etc all over the place -- but in the main upland ranges there is complex topography made up of landslide scars and debris accumulations, cirques, morainic ridges and even some features that look like outlet glacier troughs.

There have been several glaciations, but the LGM features are quite well mapped, and there appear to have been two ice caps, one in the west and the other in the east.  Both of them formed on extensive plateau surfaces more than 1,000 m above sea level.  These were perfect breeding grounds for Weichselian / Devensian glaciers -- formed from thickening snowfields and icefields which kept on growing until they started flowing outwards and over the edges of the plateau.  While glacier ice was present, volcanic activity was ongoing -- rather as in Iceland today.

The “Chaîne des Puys” is comprised of a series on monogenetic volcanoes, formed between 70,000 and 6,000 years ago, as well as the Limagne Fault, which forms the western edge of the Limagne Graben.

We stayed in Groire, Murol, not far from Clermont Ferrand to the NE and Puy de Sancy (1,886 m) to the SW.  Unfortunately the weather was too unsettled for us to go and check it out -- but we caught many fascinating glimpses of what must be glacial traces in the nearby upland ridge around Mont Dore.

Chateau de Murol, perched on top of a very fine volcanic plug.

Uplands near Puy de Sancy

In the LGM there were six or seven small ice caps in the Massif Central, some of them less than 20 km in diameter.  The largest was in the west, incorporating the uplands of Cantal, Sancy and Mont Dore; this was around 100 km from north to south and about 60 km from west to east.  It was more active than the others because it received greater precipitation than the others, but there were no distinct long outlet glaciers.  Some of the LGM outer moraines have been mapped, but the Riss moraines appear to indicate a more extensive and maybe more protracted glacial episode.

On the left, the known ice caps of the Massif Central, and on the right, the known limits of the Cezallier / Cantal ice cap. The photo at the head of this post was taken at the extreme northern edge of the area affected by the ice cap.