What is weathering?
Earth's surface is exposed to water, wind, ice, and growing plants. Each of these can break down rocks into smaller pieces. Weathering is breaking down and wearing away rocks. There are two types of weathering. Physical and chemical weathering. Physical weathering is where rocks breakdown without altering their composition. For example the Colorado River is a water source that slowly carved the Grand Canyon. It took about 6 million years. Chemical weathering breaks down the bond of rock and can be seen in oxidation of rocks. For example, when you see a rock that has rust on it, then it has been chemically altered.