By: Libby Thien
Weathering is the breaking down of rocks and minerals on Earth's surface. Weathering wears away exposed surfaces over time. It smoothes sharp, rough areas on rocks. It also helps create soil as tiny bits of the rock would mix with plant and animal remains. Weathering can be a mechanical or a chemical process. Often, these types of weathering work together. When ever the weather outside is either hot or cold the rock could expand or contract. When you look at a mountain range and see piles of loose boulders and debris from landslides, it is weathering that has loosened them from the solid rock of the mountain. Also water gets into cracks and joints in bedrock. When the water freezes it expands and the cracks are opened a little wider. Over time it could make a big boulder break into smaller rocks and gravel. This process can also break up bricks on buildings.
Mechanical weathering processes tear apart rocks by breaking them, by physically destroying them. During mechanical weathering, no new substances are produced. The rock gets smaller, but it stays the same kind of rock. Mechanical weathering is a physical process that is constantly happening in nature because nature is always active.
Chemical weathering is the break down of rocks atom by atom. Water plays an important role here, it carries small pieces to and from the microscopic sites at which chemical weathering takes place. Chemical weathering is what happens when rocks are broken down.
That is the two types of weathering and what weathering is and does.
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