Mechanical weathering breaks rocks into smaller pieces without changing their composition. Ice wedging and abrasion are two important processes of mechanical weathering. Chemical weathering breaks down rocks by forming new minerals that are stable at the Earth's surface.

“Mechanical weathering is the breakdown of rocks into sediments through physical means. For example, weathering can carve out potholes in our streets, break down rocks to form soils, and even tear down mountains.”

Mechanical Weathering Mechanical weathering, also called physical weathering and disaggregation, causes rocks to crumble. Water, in either liquid or solid form, is often a key agent of mechanical weathering. For instance, liquid water can seep into cracks and crevices in rock.

Examples of mechanical weathering that can weaken rock include the following : Thermal expansion: temperature changes make rocks expand and contract. Frost weathering (ice wedging): water in the cracks of rock freezes and expands, making the crack bigger.

What Are the Types and Examples of Mechanical Weathering? In general, geologists identify 5 main types of mechanical weathering: Thermal expansion, frost weathering/wedging, exfoliation, abrasion, and salt weathering.

Mechanical weathering breaks rocks down into smaller fragments, and increases the surface area of the over all material. By increasing the surface area, chemical processes may act more easily upon the rock surface.

Mechanical weathering involves mechanical processes that break up a rock: for example, ice freezing and expanding in cracks in the rock; tree roots growing in similar cracks; expansion and contraction of rock in areas with high daytime and low nighttime temperatures; cracking of rocks in forest fires, and so forth.