The Erosion-Deposition Process Reshaping Earth’s surface A combination of constructive processes and destructive processes produce landforms. Erosion -is the removal of weathered material from one location to another. Main Agents: Water Wind Glaciers Gravity The rate of Erosion Factors that affect the rate of erosion include weather,climate,topography and the type of rock. The presence of plants and the way humans use land also affect the rate of erosion. Erosion occurs faster on barren land rather than land covered by vegetation. Rounding The shape can change when rock fragments bump into each other. Can range from poorly rounded to well-rounded(the more polished). Sorting As sediment is transported , it can become sorted by grain size. Well sorted=moved by wind or waves. Poorly sorted= by storm, volcanic eruption, floods. Deposition -The laying down or settling of eroded material. Sediment is deposited in locations called depositional environments. Depositional Environments The locations are land, along coasts, or oceans. The amount of energy determines the size and the amount sediment moved. The sediment is deposited when or where the energy decreases. Sediment layers(beds) Beds often form as layers of sediment at the bottom of rivers, lakes, and oceans. Interpreting Landforms Landforms created by Erosion 1. Landforms formed by erosion can expose several layers of rock. Multicolored mounds 2. Different rates of erosion can result in unusual landforms when some rocks erode and leave more erosion-resistant rocks behind. Tall & protruding 3. Glacial erosion and Coastal erosion. U-shaped valleys Landforms created by Deposition Flat & Low. Deposition along a riverbed occurs where the speed of water slows.