Water Erosion and the Cycle of Deposition and Erosion By Sarah C.
Processes that wear down the surface <ul><li>When new mountains form the cycle of erosion and deposition starts. Erosion is always happening to these mountains even when they are forming. The erosion wears down the mountains and fills the valleys (that erosion has made) with sediment. Together erosion and deposition have almost made the land flat again. When new mountains form it all starts over. </li></ul>This is an alluvial fan, it forms when a river deposits it’s sediments. http:// www.earthscienceworld.org/images/search/index.html
Applying what you know…. <ul><li>Use Google Maps and create a tour of at least 5 concepts you learned about in this unit. Add a placemark on your map along with an annotation of what can be observed at that site as well as citing the source of information. Be sure to name your placemark. </li></ul><ul><li>11/20, 11/27-11/28 </li></ul>
Key words to know in talking about weathering and erosion <ul><li>Erosion -the process by which wind, ice, water, or gravity moves weathered rock and soil </li></ul><ul><li>Sediment -earth materials deposited by erosion </li></ul><ul><li>Deposition -the process in which sediment is laid down in new places </li></ul><ul><li>Gravity -a force that moves rocks and other materials down hill </li></ul><ul><li>Mass Movement -any one of several processes which moves sediment downhill </li></ul><ul><li>Weathering -the chemical and physical processes that breaks down rocks at Earth’s surface </li></ul>
How water erosion shapes the surface. <ul><li>How can water move soil and sediment? </li></ul><ul><li>When land gets eroded by water, the water some of the soil and sediment comes with it. Then when the stream dries up the sediment and soil are left there. </li></ul><ul><li>What evidence can you find of the effects of water on Earth’s surface? </li></ul><ul><li>You can find the effects things have from eroding water. You can see meanders and oxbow lakes. You can see waterfalls and V-shaped valleys. </li></ul>This is a meander, it happens when the water on the outside of the stream moves faster, So the river curves. http:// www.earthscienceworld.org/images/search/index.html This is an alluvial fan, and it also appears from water erosion
Pictures of water erosion A river is an effect of water erosion http:// www.mbgnet.net / This is an oxbow lake. It is also something that happens from water erosion. http://www.earthscienceworld.org/images/search/index.html This is a waterfall. http:// www.waterfallsnorthwest.com / A delta (above) is a deposit by rivers. There are stalagmites and stalactites in this cave and they are caused from groundwater erosion.
Applying what you know…. <ul><li>How fast the particles depends on the river’s slope, volume of flow, and it’s streambed. The way the particles move depend on the size they are. The particles of clay will probably be suspended in the water. They will move along with the flow or current. The pebbles will move by bouncing along the stream floor. </li></ul>
Sources used to research and answer questions from the surface change and water erosion sections. <ul><li>Wysession, Michael. Earth's Changing Surface . Boston, Massachusetts: Pearson Education Inc., 2007. </li></ul>