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Weathering, in geology, processes of physical disintegration and chemical decomposition of solid rock materials at or near the

There are three main types of weathering: physical weathering, chemical weathering and organic weathering.

Factors affecting the type and rate of weathering

The main factors are the hardness of the rocks (minerals composition), the texture of rocks (their crystalline state), rock joining, relief and climate.

Rock Resistance

Rocks vary significantly in resistance to weathering. Resistance depends on the constituent minerals of the rock, the coherence of these minerals (how they are cemented together in the rocks), and the extent to which the minerals have been compressed.

System of Weathering

At one time, weathering was seen as a distinction and separate process of landscape formation. In the same way, mechanical and chemical weathering processes were regarded as separate types of weathering. Today the process of weathering is placed in the broader context of landform development and various types of weathering are seen as simultaneous and interrelated influences.

In the system analysis of landscape formation known as the rock material cascade, for example, weathering is seen as the contributing to the formation of rock waste which is the initial input into the system. The cascade is seen as being comprised of input (weathering and erosion), throughput (transportation) and output (deposition). Parts of the deposited output are cycled back into the crystalline rocks where the cascade begins again.