Leaving Certificate Geography Practice Test 2026 – Complete All-in-One Guide for Exam Success!

Weathering refers to the breakdown of rocks into smaller pieces through various processes. This can occur in three main forms: physical, chemical, and biological weathering.

Physical weathering involves the mechanical breakdown of rocks without changing their chemical composition, often due to temperature fluctuations, freeze-thaw cycles, or pressure changes. Chemical weathering, on the other hand, alters the chemical structure of the minerals in the rocks, usually through reactions with water, acids, or other chemicals present in the environment. Biological weathering is a process where living organisms, such as plants and microbes, contribute to the weathering of rocks, often by secreting acids or by physical root growth that cracks the rocks apart.

The other options relate to geological processes, but they do not define weathering. Soil erosion involves the removal of the top layer of soil by water or wind, which is a separate process that can occur after weathering has already broken down rocks into soil. The movement of sediments pertains to processes like sediment transportation or deposition, which typically follows weathering and erosion. The transformation of minerals under high pressure describes metamorphism, a different geological process where existing rocks change form but does not pertain to the breakdown of rocks involved in weathering. Thus, the correct