Mechanical weathering is the breakdown of rock into particles without changing the identities of the minerals in the rock. Ice is the most important agent of mechanical weathering. Water percolates into cracks and pore spaces, freezes, and expands. The force exerted is sufficient to widen cracks and break off pieces, in time disintegrating the rock. Heating and cooling of the rock, with resulting expansion and contraction, also helps. Mechanical weathering contributes further to the breakdown of rock by increasing the surface area exposed to chemical agents. The breakdown of rocks and erosion of the fragments has been greatly accelerated over the past several centuries by the activities of man through farming and construction.
Mechanical weathering is the breakdown of rock into particles without changing the identities of the minerals in the rock. Ice is the most important agent of mechanical weathering. Water percolates into cracks and pore spaces, freezes, and expands. The force exerted is sufficient to widen cracks and break off pieces, in time disintegrating the rock. Heating and cooling of the rock, with resulting expansion and contraction, also helps. Mechanical weathering contributes further to the breakdown of rock by increasing the surface area exposed to chemical agents. The breakdown of rocks and erosion of the fragments has been greatly accelerated over the past several centuries by the activities of man through farming and construction.
Not applicable at this reading level.
