Wind is the agent of erosion that creates sand dunes. The wind blows grains of sand into a sheltered or otherwise secure location, allowing gradual accumulation.Know More
Each dune features a windward face and a slip face. The windward face is the area where the sand is blowing and pushing materials upward. The slip face is the side that does not experience wind. Dunes that are formed underwater experience a similar phenomenon but through currents of water instead.
Sand dunes are classified by shape. Crescentric dunes are crescent-shaped, while linear dunes are mostly straight. Star dunes occur when wind from many different directions blows sand. Dome dunes are circular, lacking a slip face. Parabolic dunes are formed by wind that blows outward from their center.Learn more about Erosion & Weathering
Beach erosion, often referred to as coastal erosion, occurs when the area’s sand is washed into the ocean. Beach erosion is a constant process, and the persistence of a beach depends upon local rivers and streams to transport more sand to the area. If the area loses more sand than it gains, it begins to shrink over time.Full Answer >
"Wave erosion" occurs when the energy and pressure of waves combines with the chemical composition of water to erode rock and sand. Wave erosion is also known as coastal erosion and occurs not only in oceans, but also in other large bodies of water.Full Answer >
Wind and water erosion are least likely to affect igneous sills and cooled lava flows. Limestone, basalt and quartzite are also unlikely to undergo erosion or weathering, as are sandstone and chert. Soil and soft rocks such as clays erode very quickly without protection.Full Answer >
Headward erosion occurs when the source of a stream channel is lengthened by erosion of the rock and soil in its basin. This type of erosion occurs in the opposite direction of the flow of the stream.Full Answer >