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12 Erosion/ ition EROS ION I s the remova I and s I mu I taneous transportat I on of earth materials from one location to another by water, wind, waves. or moving Ice. DEPOSITION Is the placing of the eroded material In a new location. All material which. is 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 rapid local erosion as the water carries 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, tailings 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 while soft slits and sands erode very quickly. Vegetation which holds soils 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 culverts, aggravate flooding, destroy crops and lawns by burying them, and reduce the capacity of water reservoirs as the deposited materials displace water. Severe erosion from man-made alterations of the dra i nage systems resu I ted in a large gu I I Y I n Doug I as Note man standing In the center of the picture. natural County.