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Shaping Earth’s Surface |
A glacier is a large mass of snow and ice that moves over land. Glaciers are formed when more snow falls in winter than melts in summer. Over time the snow collects in layers, which turns the lower layers into ice. The weight of the snow causes the layers to flow downhill. Glaciers contain debris which is found at the bottom and along the sides of the glacier. Bedrock is a rock that comes in contact with solid rock below the soil.
The features of a glacier are terminus, moraines, and glacial till. Terminus is at the end of a glacier. Moraine is rock debris left behind. Glacial till is anything made by ice or glaciers. Glaciers create steep cliffs, circular basins, and U shaped valleys.
Erratics are glaciers left behind long ago. Outwash plains are gravel, sand and clay carried from glaciers by melting water and streams. An ice age is a long period of very cold temperatures and many glaciers. Interglacial periods are periods of warmer weather that existed between ice ages.
Wind erosion picks up small particles of dust, soil and sand. Over time these particles wear down exposed surfaces. Waves carry away materials and break up rocks and deposit them elsewhere. A delta is made up of particles picked up from far away and dropped at a river’s mouth. Gravity moves loose materials from high to low places. It causes landslides and mudflows. |
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