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What is EROSION?. I. Erosion . A . Erosion is a process that moves weathered rock and soil from one place to another. B. Gravity, Water, Glaciers, Waves, and Wind can all cause erosion. C. Weathering produces sediment, but erosion moves it.
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I. Erosion A. Erosion is a process that moves weathered rock and soil from one place to another. B. Gravity, Water, Glaciers, Waves, and Wind can all cause erosion. C. Weathering produces sediment, but erosion moves it. D. Deposition lays down the sediment, which changes the shape of the land. E. Weathering, erosion and deposition act together in a cycle that wears down and builds up Earth’s surface.
II. Gravity • Mass movement is the process that moves sediment downhill by gravity. • Mass movement can be rapid or slow. • Different types of mass movement include landslides, mudslides, slumps, and creeps.
Slumps often occur when water soaks the base of a mass of soil that is rich in clay. Unlike a landslide, the material in slump moves down in one large mass.
III. Water Erosion • Moving water is the major agent of erosion. B. Erosion by water begins with splashes of rain. C. Through erosion, rivers create valleys and waterfalls.
Channels caused by water erosion in the Coconino Sandstone, West Beaver Creek Canyon
IV. Ice Erosion • Ice erosion is caused by the movement of ice, typically glaciers. • A glacier is any mass of ice that moves slowly over land. • Glaciers can form only in areas where more snow falls than melts. • Glaciers erode by two processes: abrasion and plucking, in which glaciers pick up rocks when it moves and carries the rock with it.
Valley Glacier is a long narrow glacier that forms when snow and ice build up in a mountain valley.
V. Wave Erosion A. Waves are a major force of erosion along coasts. B. Waves also erode land by abrasion. C. Waves can hit rocks along the shore with great impact and break the rocks apart.
VI. Wind Erosion A. Wind is the weakest agent of erosion. B. However, wind is very effective in causing erosion in deserts. C. The main way wind causes erosion is by picking up small particles of sediment, moving it through the air allowing it to fall back to the ground, called deflation. D. Sand dunes, a deposit of wind blown sand, are created by wind erosion.
