Question

Read the passage given below and answer the following questions.

Weathering refers to the fragmentation of the rocks (but not its removal), either due to the mechanical disintegration or chemical decomposition. It is the first step of denudation and provides the base for the subsequent processes, namely, erosion and mass movements to take place. The chief agents of weathering are the weather elements such as temperature and precipitation. The rate of weathering in a region depends upon its climatic conditions. For example, in desert type of climate, where the variations in temperature are on daily basis in the form of high diurnal range of temperature, the rate of weathering is high. Similarly in moist climate, for example, the Equatorial type of climate, which is hot and humid, the rate of weathering is high.

1. What is the term used for the removal of the weathered rock particles?
2. Why is it said that weathering provides the base for erosion and mass movement to take place?
3. Which type of weathering takes place in the areas where the diurnal range of temperature is high?

Answer 1

1. The term used for the removal of the weathered rock particles is “erosion.” Weathering refers only to the fragmentation of rocks, not their removal; the removal happens through erosion and mass movements.
2. Weathering is said to provide the base for erosion and mass movement to take place because it breaks down the rocks into smaller pieces while still in situ (at the original place). These broken pieces then serve as material that can be moved by erosion (carrying away) and mass movements (downhill movement), which leads to the evolution of landforms and landscape changes.
3. The type of weathering that takes place in areas where the diurnal range of temperature is high (such as desert climates) is physical or mechanical weathering called “block weathering.” This occurs due to fluctuations in temperature, where rocks expand during the hot daytime and contract during the cold night, leading to disintegration without chemical change.