The black cotton soil of India has been formed due to the weathering

The black cotton soil of India has been formed due to the weathering of

[amp_mcq option1=”brown forest soil” option2=”fissure volcanic rock” option3=”granite and schist” option4=”shale and limestone” correct=”option2″]

This question was previously asked in
UPSC IAS – 2021
The correct answer is B) fissure volcanic rock.
– The black cotton soils of India, also known as Regur soils, are predominantly found in the Deccan Plateau region.
– These soils are formed by the weathering of basaltic lava rocks, which are the result of massive fissure volcanic eruptions that occurred during the formation of the Deccan Traps in the late Cretaceous period.
– Basalt is a type of extrusive igneous rock formed from the rapid cooling of magnesium-rich and iron-rich lava exposed at or very near the surface of a terrestrial planet or a moon.
– Black cotton soils are rich in clay minerals like montmorillonite, which causes them to swell when wet and shrink when dry, leading to characteristic cracks. They are known for their fertility and suitability for cotton cultivation, hence the name.
– Weathering of granite and schist typically produces red or yellow soils (e.g., in the Peninsular Plateau).