These plate cycles may also lead to volcanic activity. For example, the Pacific Ocean is surrounded by a nearly continuous plate-collision zone, called the 'Ring of Fire'. Both earthquakes and volcanoes are the results of the instability of this zone. There are different forces that erode the earth s landforms. Weathering is the physical disintegration and chemical decomposition of earth materials at or near the earth's surface.
Water is a mechanical weathering force.
Evidence shows that water molds the earth's surface through, rivers, and ocean waves. One of the largest examples of water as a weathering force is the Grand Canyon. The Colorado River has molded and shaped the canyon over the last 5 million years. Physical weathering breaks rocks into pieces. Animals, insects, worms, and burrowing mammals all work to loosen the soil by aeration and by mixing loose materials.