ABSTRACT
GLACIAL EROSION Glaciers form where winter snowfall exceeds summer melt; snow layers accumulate, compressed lower zones recrystallize and are squeezed out as flowing ice. Most glaciers move about a metre per day. Pleistocene glaciated areas are most easily recognized by erosional landforms. Alpine glaciation: valley glaciers in mountain areas of high relief; ice further deepens U-shape valleys between high uneroded arête ridges. Sheet glaciation: thick ice moves over entire landscape; greater erosion of high ground reduces relief; ice can erode while moving uphill, to create irregular topography with over-deepened rock basins.
