Erosion processes

• Freeze thaw: Water gets into cracks in exposed rock, temperatures drop then water freezes and expands, this enlarges the crack, the ice thaws and process repeat until eventually the rock breaks off.
• Freeze thaw steepens the wall of a corrie and leaves it jaggy.
• Plucking: Ice freezes onto loose rock (from freeze-thaw) on the back wall of glaciers, as glacier moves downhill it pulls the loose rocks with it.
• Plucking steepens the walls and leaves them jagged.
• Abrasion: Rock at the bottom of the a glacier (from freeze thaw and plucking) are dragged along the base of the hollow as the glacier moves downhill, this scrapes away at the rock.
• Abrasion smooths and deepens the base of the corrie.