| Summary: | The distribution of ice-scoured landscapes correlates with zones of basal ice melting as reconstructed for a Pleistocene Scottish ice sheet. Areas of no apparent ice sheet erosion are associated with a zone of basal ice freezing. The morphological and morphometric characteristics of ice-scoured landscapes and landforms are more closely- related to bedrock lithology and structure, in particular to patterns of bedding plane strikes and dips, joints and faults, than to ice-movement directions . Where the latter were perpendicular to the strike of bedrock structures dipping up-ice, hierarchies of typical roche moutonnee forms are developed with plucked and cliffed lee-side facets. However, where the ice flow direction and the strike of the structures were sub-parallel, the plucked and cliffed facets occur parallel to the former. In some massive rocks fresh fracturing of the bedrock may occur on the lee sides of obstacles and is thought to be related to a process of glacier crushing. The correlation structure of a number of cirque morphometric variables indicates that as cirque size increases, the degree of enclosure in plan, profile and overall dimensions increases. Also length tends to increase relative to amplitude, but' length to breadth ratio remains relatively constant. A space-time transformation suggests that dimensional cirque equilibrium forms are not present. However, dimensionless equilibrium forms appear to be developed in plan and also at an overall level. Cirque headwall retreat proceeds slightly faster than downcutting, but there is no evidence for widespread landscape destruction by cirque erosion. The form of the pre-glacial relief may be more important in explaining variationa in the character of cirque landscapes. Variations in cirque morphometry tend to be a function of local-scale factors, in particular the maximum altitude of the area draining into each cirque.
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