glaciated landscapes

• freeze-thaw weathering: when water freezes and expands, it cracks rocks.
• corries form when snow falls into a north to north-east facing hollow and cant melt as it is facing away from the sun. over time a glacier forms as the snow builds up. the glacier starts to move under it's own weight and the force of gravity.
• plucking steepens the back wall of the corrie. plucking happens when the glacier comes across rock loosened by freeze-thaw weathering. the process of plucking is made easier if the rocks have been weathered by freeze-thaw.
• the plucked rocks are used to abrade the base of the hollow. abrasion deepens and smooths out the hollow by grinding away the ground beneath.
• once the glacier is melted an arm-chair shaped hollow is revealed. a rock lip is formed as a result of depositing plucked and abraded moraine. this accompanied by over deepening of the hollow causes a lip to form (but not always) on the back wall of the corrie freeze-thaw weathering creates a build up of scree.
• Aretes form when there are two corries back to back. freeze-thaw weathering steepens the backs of the corries, meaning they retreat towards each other. a sharp ridge forms between the two corries
• a pyramidal peak forms when there are 3 or more corries back to back. freeze-thaw weathering steepens the backs walls of the corries, meaning the corries retreat towards each other. a sharp peak forms between the corries
• The u shaped valley is formed when a glacier flows out of a corrie and looks for the quickest route it can take downhill. this is via an existing V-shaped valley. plucking steepens the sides of the valley. abrasion flattens and widens the floor of the valley. the interlocked spurs of the V-shaped valley are bulldozed as the glacier advances. this creates truncated spurs.
• when the glacier retreats a steep sided wide and flat floored valley is revealed. the river that flowed through the original V-shaped valley starts to flow once again however, now it's called a misfit stream as it is too small to have created the valley itself