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12 Erosion/ ition EROSION is the removal and simultaneous transportation of earth materials from one location to another by water, wind, waves, or moving Ice, DEPOSITION Is the placing of the eroded mater i a I in a new I Deat ran. A II mater i a I wh i ch j 5 eroded Is later deposited in another location. Characteristics Erosion and deposition are occurring continually at varying rates over the earth's surface. Swiftly moving flood waters cause rap i d I Dca I eros i on as the water carr i as away earth materials. Deposition occurs where flood waters slow down, pool or lose energy In other ways and the materials settle out. Simi larly, wind erosion can occur from exposed areas such as fields, tal I logs and desert areas when the wind is strong and the materials are deposited when the wind diminishes. Another factor which controls the amount of erosion is the ease with which material can be dislodged. Hard granites erode very slowly whi Ie soft si Its and sands erode very quickly. Vegetation which holds sol Is in place can decrease significantly the rates of erosion from water and wind. Consequences Erosion can result in minor inconveniences or total destruction. Severe erosion removes the earth from beneath bridges, roads, and foundations of structures adjacent to streams. By undercutting it can lead to increased rockfal I and landsl ide hazard. The deposition of material can block cu I verts, aggravate f I oDd i ng, destroy crops and I awns by burying them, and reduce the capacity of water reservoirs as the deposited materials displace water. Severe erosion from man-made alterations of the natural drainage systems resulted in a large gully In Douglas County. Note man standing In the center of the picture.