What is weathering?

• A. The process of breaking down rocks into smaller pieces through physical or chemical means.
• B. The movement of soil by wind.
• C. The deposition of sediments.
• D. The formation of rocks from molten lava.

Answer: (A)

Weathering is the breakdown of rocks into smaller pieces through physical or chemical processes, happening in place at or near the surface. Physical weathering includes freeze-thaw cycles that crack rocks, abrasion from wind or water, and plant roots pushing rocks apart. Chemical weathering involves reactions that weaken or dissolve minerals, such as rainwater forming weak acids that dissolve minerals or oxidation that changes minerals to different compounds. Weathering gradually reshapes rocks and contributes to soil, but it does not move rock material away—that’s erosion. The other descriptions refer to erosion (movement of sediment by wind or water), deposition (settling of sediments), and rock formation from molten lava (igneous processes).