Weathering
Topic: Geomorphic Processes: Weathering, Mass Movement, Erosion and Soil Formation · NCERT: Class 7, Ch 1 "The Story of Indian Farming"; Class 9, Ch 2 "Shaping of the Earth's Surface"; Class 11, Ch 5 "Geomorphic Processes"
Meaning
Weathering is the mechanical breaking (disintegration) and chemical rotting (decomposition) of rocks by weather and climate. It happens in situ, meaning in place, and little or no material moves. Climate matters most, so the weathered layer is deepest in the humid tropics and thin in deserts and polar zones. Weathering produces regolith (loose rock cover) and soil. It also prepares material for mass movement and erosion.
Example
At Hampi in Karnataka, granite has weathered along its joints (natural cracks). This has left piles of rounded boulders called tors.
Don't confuse with
- Erosion: this needs an agent, such as water, wind or ice, to carry material away. Weathering breaks rock where it stands.