The Changing Earth

The Changing Earth Erosion is the transportation of weathered pieces of bedrock through the agents of wind, water (rivers and ice), and gravity. As mountains are built up by tectonic forces, they are also broken down and carried away by weathering and erosion. The pull of Gravity makes surface material move downward. Downslope movements may be rapid or very slow. They may involve only the surface material, or they may involve the bedrock underneath. Houses …

…large as the Grand Canyon. As rivers erode land, they carry deposits with them. DELTAS are formed at the mouths of rivers that empty into a lake or an ocean. The soil that is carried along a river and deposited as its mouth is the richiest and most fertile of all soils. The Nile and the Mississippi Rivers have formed deltas that are noted for their rich soil, making these regions highly desirable for agriculture.