I was looking at some photos of glacial things the other day when I came across this one. It shows landslide debris on the surface of a small glacier near Mont Blanc, in the French Alps. You can see the scar left on the mountainside following the landslide, and also the disruption on the snowy surface right at the head of the glacier caused by thousands of tonnes of debris ploughing downslope. The glacier will now carry this debris inexorably further and further away from its source -- and eventually, maybe after decades or centuries, it will be dumped as an erratic train or as a "cluster" of erratics like the Darwin Boulders of Tierra Del Fuego (see earlier posts on this topic -- use the search facility.)
We have had much discussion on this blog about the Foothills Erratic Train of North America; it is thought that the material which makes up that "trail"of erratics was dumped following a series of "landslide events" high above the glacier surface near Jasper, Alberta. The scene following each event will have been very much like that shown in the photo above.
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