As a glacier moves, it alters the landscape in two main ways:
Plucking – Glacial meltwater flows underneath glaciers, which helps to lubricate the glacier’s movement. Plucking occurs when meltwater under a glacier freezes on the rock surface. As the glacier moves forward, it pulls away large pieces of rock from the surface.
Abrasion – As the glacier moves, it transports pieces of rock with it, which help the glacier to shape and wear away the landscape. As the pieces of rock in the ice grind against the rock over which the ice is moving – like rough sandpaper – the land is worn away.
A glaciated valley
A glacier can "carve" a valley, wearing away rocks and soil through abrasion and plucking up and moving large pieces of rock and debris. The glacier pushes this frozen earth and rock forward as it advances, like a bulldozer and dumps it to the side along the way or at the end of the glacier (deposition).
Glaciers & Glaciation
