Roches moutonnées are classic landforms of glacial erosion (Bennett and Glasser, 1996). They are giant stoss and lee forms carved from bedrock, with smoothly abraded up-ice or stoss faces and roughly quarried/plucked down-ice lee faces. They can occur as isolated forms, can be superimposed on larger asymmetric landforms, or occur as part of erosional landscapes subject to regional scour. Individual forms vary in size from less than 1 m to several hundred meters or even kilometers in diameter (Rastas and Seppälä, 1981). In Sweden, for example, large asymmetric hills (Flyggbergs) exceed 1 kilometer in length; however, most roches moutonnées are much smaller.
Roches moutonnées are the product of both glacial abrasion and glacial quarrying and it is this combination of processes that results in the asymmetric profile. Glacial abrasion occurs on the up-ice or stoss face of the landform, while glacial quarrying occurs on the lee. Glacial quarrying involves two processes, firstly the...
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