What is the name for the process by which rocks are broken down into smaller pieces?

The process of breaking down rocks into smaller pieces is known as weathering. This phenomenon occurs through various mechanisms, including physical processes such as freeze-thaw cycles, where water infiltrates cracks in rocks, freezes, and expands, leading to the disintegration of the rock. Additionally, chemical weathering involves chemical reactions that alter the minerals within the rocks, further contributing to the breakdown.

Weathering is distinct from processes like subduction, which refers to one tectonic plate being forced under another, and metamorphism, which involves the transformation of rocks under heat and pressure without melting. Denudation relates to the overall wearing away of the Earth's surface, encompassing both weathering and erosion, but does not specifically focus on the breakdown of rocks into smaller pieces. Understanding weathering is essential in geology as it plays a critical role in soil formation, landscape evolution, and the rock cycle.