Glaciers form in places where snow piles up, rather than melts. Glaciers appear stationary, however they are constantly moving. The ice moves down the slope due to the force of gravity. There are two types of glaciers, continental glaciers, and valley glaciers. A continental glacier is a thick sheet of ice that covers a huge area, such as a continent, or a massive island. A valley glacier is a glacier that is found in a high mountain valley. Glaciers erode the earth while traveling downhill. Glaciers move rock by abrasion and plucking. Plucking is when glacial ice widens cracks in the bedrock beneath the glacier. Glacial erosion causes many distinctive features in the landscape including and not limited to cirques, horns, U-shaped valleys, and glacial lakes. Glaciers can also carve huge bowl-shaped valleys out of a mountainside. These are called cirques. When a glacier melts, it deposits its load of sediment (till) creating landforms.
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