Indo-Gangetic Plain, also called North Indian Plain, extensive north-central section of the Indian subcontinent, stretching westward from (and including) the combined delta of the Brahmaputra River valley and the Ganges (Ganga) River to the Indus River valley. The region contains the subcontinent’s richest and most densely populated areas.
The greater part of the plain is made up of alluvial soil, deposited by the three main rivers and their tributaries. The eastern part of the plain has light rains or drought in the winter, but in summer rainfall is so heavy that vast areas become swamps or shallow lakes.
The plain becomes progressively drier toward the west where it incorporates the Thar (Great Indian) Desert.
PLATE TECTONICS & FORMATION OF NORTHERN PLAINS
- Due to the uplift of the Himalayas in the Tethys Sea, the northern flank of the Indian Peninsula got subsided and formed a large basin/ trough. That basin was filled with sediments from the rivers which came from the mountains in the north and from the peninsula in the south. Thus, an extensive flat land of alluvial soil was formed which is known as the northern plains of India.
From the north to the south, these can be divided into three major zones: the Bhabar, the Terai and the alluvial plains. The alluvial plains can be further divided into the Khadar and the Bhangar.
Bhabar:
- Lies at the foothills of Shivalik.
- It is porous and pebbled plain and hence not suitable for agriculture.
- The rivers flowing through this region disappears.
Terai:
- Lies south of the Bhabar.
- Rivers re-appear on the surface and thus it has waterlogged conditions.
- Covered with dense forests.
Bhangar:
- It is made up of old alluvium.
- It is mainly present in Ganga-Yamuna doab and Doabs of Satluj.
Khadar:
- It is made up of new Alluvium.
- It is a low land and hence flood water reaches it frequently.
- Eastern U.P, Bihar and West Bengal has its presence.
REGIONAL DIVISION
Indus Plain:
- The plain west to Indus is made up of mainly Bangar constituents and East of the rivers has deltaic relief.
- Numerous saliferous lakes are found near dry beds.
Punjab plains:
- Bist doab – > between Beas and Satluj
- Bari doab -> Between Beas and Ravi
- Rachna doab -> between Ravi and Chenab
- Chhaj doab -> between Chenab and Jhelum
- Sindh Sagar doab -> between Jhelum-Chenab and Indus
Gangetic plains:
- Upper Gangetic plain -> Western U.P
- Middle Gangetic plain -> Eastern U.P + Bihar
- Lower Gangetic plain -> West Bengal
Brahmaputra plains:
- Situated between Himalayas and Meghalaya plateau.
- Majuli (largest riverine island) in Assam is built on it.
Rajasthan plains:
- It extends from west of Aravallis.
- It is divided into two parts; the Eastern part is ‘Rajasthan Bangar’, and the Western part is ‘Thar desert’
- Many Barkhans (crescent shaped sand dunes) are present here.
