Soils of India Quiz

Study Notes

A horizon sits above the C horizon and includes soils formed on various substrates such as sand dunes and volcanic materials.
Various agencies, including the Soil Survey of India (1956), have conducted comprehensive soil surveys post-Independence.
The Indian Council of Agricultural Research (ICAR) classified Indian soils based on USDA Soil Taxonomy.
Indian soils are classified into categories like Alluvial, Black, Red and Yellow, Laterite, Arid, Saline, Peaty, and Forest soils.

Alluvial soils cover approximately 40% of India, primarily located in northern plains and river valleys.
These are depositional soils transported and deposited by water bodies.
In Rajasthan, they extend to Gujarat, and they are also found in peninsular deltas and river valleys.
In the Ganga plain, alluvial soils divide into Khadar (new alluvium deposited annually by floods) and Bhangar (older alluvium).
Khadar is enriched by annual floods while Bhangar is located further from floodplains.
Both Khadar and Bhangar contain calcareous concretions known as Kankars.

Seismometers measure ground motion caused by seismic waves from earthquakes and volcanic eruptions.
Seismographs, an older term for seismometers, record seismic activity, producing a seismogram.
The Mercalli Scale measures earthquake intensity based on observed effects, ranging from 1 to 12.
The Richter Scale quantifies earthquake magnitude, with each whole number indicating a tenfold increase in power.

Circum-Pacific Zone: Predominantly features subducting oceanic plates with varying depths of earthquake foci (300-700 km).
Mediterranean and Trans-Asiatic Zone: Characterized by shallow to intermediate earthquakes due to continental plate collisions.
Mid-Oceanic Ridges and African Rift System: Experience shallow-focus earthquakes along ridges and rift zones.
In India, four seismic zones are identified based on historical seismic activity: Zone II, III, IV, and V.

Nebular Hypothesis: Proposed by Immanuel Kant and revised by Laplace, suggesting planets formed from a rotating cloud of material around a young sun.
Planetesimal Hypothesis: In 1900 by Chamberlain and Moulton, positing a wandering star's proximity to the sun influenced planet formation.
Binary Theories: Suggests a companion star to the sun existed alongside it during the formation of the solar system.
Big Bang Theory: Introduced by Edwin Hubble, stating the universe began from a singular point around 15 billion years ago, resulting in an expanding universe and creation of galaxies, stars, and planets.