Erosion

Erosion is the process of natural forces moving rocks and soil. Rocks and soil can be referred to as earth materials.

The natural forces that make erosion happen are:

water	water	Happens when water moves the pieces of rock or soil downhill and carries small pieces of material with it.
	waves	Carry away small pieces of material. A wave can wash up onto the surface of rock or soil and then carry away pieces of material as it flows back into the ocean or lake.
Wind		Occurs when wind moves pieces of earth materials. Wind erosion is one of the weakest kinds of erosion. Small pieces of earth material can be rolled along the ground surface by wind. Very small pieces can be picked up and carried by the wind. Occasionally, wind can carry small pieces of earth materials over large distances.
Ice		Usually happens when a glacier moves downhill. As the ice of the glacier moves downhill, it pushes and pulls earth materials along with it. Ice erosion is one of the strongest kinds of erosion because glaciers can move very large rocks.
Gravity		Is the simplest kind of erosion. Gravity simply pulls loose earth materials downhill. Landslides are dramatic examples of gravity erosion).

Erosion is a geological process. Geology is the study of the structure of the earth and the processes that change the earth. Erosion occurs only at the earth's surface.

Most of the energy that makes erosion happen is provided by the sun. The sun's energy causes the movement of water and ice in the water cycle and the movement of air to create wind. If the sun did not provide energy for erosion, only gravity erosion would still occur.

Erosion can cause problems that affect humans. Erosion can also cause problems for humans by removing rocks or soil that support buildings.