Glacial erosion refers to the processes by which glaciers modify the landscape through the removal and transportation of sediment and bedrock. This is primarily achieved through the actions of plucking and abrasion.
Plucking
Plucking occurs when glaciers pick up rocks and sediments as they flow over bedrock. As the ice melts and refreezes, it can "pluck" or pull loose pieces of rock from the underlying surface, transporting them with the glacier as it moves.
Abrasion
Abrasion is the process by which the glacier grinds and wears away the bedrock beneath it as it moves. The debris carried by the glacier acts like sandpaper, smoothing and polishing the underlying rocksurface.
Glacial erosion results in the formation of several distinct landforms, including:
U-shaped valleys:Glaciers carve out deep, wide valleys with gently sloping sides, creating a characteristic "U" shape.
Cirques: Bowl-shaped depressions formed at the head of glacial valleys as a result of erosion by the glacier.
Arêtes and horns: Sharp-edged ridges (arêtes) and pyramid-shaped peaks (horns) created by the erosive action of glaciers on multiple sides of a mountain.
Fjords: Deep, narrow inlets of the sea with steep cliffs, formed by the submergence of glacially carved valleys.
