Science Essay

How do mass movements and fluids transform or change landforms?

Mass movement and fluids change landforms because of gravity. Gravity is the force that moves rock and other materials, pulls everything toward the center of the earth, causes mass movements which is one of several processes that move sediment downhill. It happens when one of the four types of movements occur. The four mass movements are landslides, mudflows, slump, and creep. Landslides are the most dangerous movements, it happens when rock or soil slide quickly down on slope. Slumps are a mass of rock and soil suddenly slips down a slope. Creeps are a slow downhill movement of rock and soil. It takes place on gentle slopes. Mudflows are rapid downhill movement of mixtures of water, rock, and soil. An example of Mudflows is erosion. Erosion is the process by which natural forces move weathered rock and soil from one place to another. When you see water carrying soil and gravel down a driveway after it rains, it is an example of erosion. Then there is water erosion, Erosion is what destroys houses and landscapes due to rain, which erodes the soil and causes rills and gullies, streams and rivers, and tributaries erosions. Moving water is the major agent of the erosion that has shaped the Earth’s land surface. When the rain moves it carries particles with it, this moving water is called Runoff. Runoff is water that moves over the Earth’s surface, When Runoff travels, it forms tiny grooves in the soil which rills. A gully is a large groove or channel in the soil that carries runoff after a rainstorm. They join together to form a larger channel called a stream. A stream is a channel along which water is continually flowing down a slope, unlike gullies, streams rarely dry up.  Small streams are also called creeks or brooks, a large stream is often called a river, and a stream gets larger by receiving water from tributaries. A tributary is a stream or river that flows into a larger river. For example, the Missouri and Ohio rivers are tributaries of the Mississippi River. Through erosion, a river creates valleys, waterfalls, flood plains, meanders, and oxbow lakes. Waterfalls may occur where a river meets an area of rack that is very hard and erodes slowly. A waterfall forms where a flat layer of tough rock lies over a layer of softer rock that erodes easily. When the softer rock erodes, pieces of the harder rock above break off, creating the waterfall’s sharp drop. During this process, the river spreads out and erodes the land, forming a wide river valley. The flat, wide area of land along a river is a flood plain. A river often develops meanders where it flows through easily eroded rock or sediment. A meander is a loop like bend in the course of a river. The southern stretch of the Mississippi River is one example of a river that meanders on a wide, gently sloping flood plain. Sometimes a meandering river forms a feature called an oxbow lake. An oxbow lake is a meander that has been cut off from the river. An oxbow lake may form when a river floods. As the flood waters fall, sediments dam up the ends of a meander. The meander has become an oxbow lake.