N.K. Chauhan 
The northern plains are about 2400 KM long and 240 to 320 KM broad alluvial deposits brought formed by the interplay of the three major river systems - the Indus, the Ganga, and the Brahmaputra along with their tributaries.
It is a densely populated physiographic division of rich soil cover, adequate water supply and agriculturally favorable climate.
1) Bhabar plains
Bhabar plains consists of the northern most layer of the plains, the width of this region is not uniform and it is wider in West(15 KM) than in East(8KM).The streams and rivers coming from the mountains, deposits heavy materials of rocks and boulders, and at times, disappear in this zone.
The porosity is due to deposition of huge number of pebbles and rock debris across the alluvial fans.
The area is characterized by big trees and is not suitable for cultivation.
2) Terai plains
Terai is an 15-30 km wide, ill-drained, damp (marshy) and thickly forested narrow tract to the south of Bhabar running parallel to it.The underground streams of the Bhabar belt re-emerge in this belt.
Terai has a luxurious growth of thickly forested natural vegetation and houses a varied wildlife.
Jim Corbett National Park in Uttarakhand and Kaziranga National Park in Assam lie in terai region.
The Terai spreads from the Yamuna River eastward across Haryana, Uttarakhand, Uttar Pradesh, Bihar and West Bengal.
Most of the Terai land, especially in Punjab, Uttar Pradesh and Uttarakhand, has been turned into agricultural land which gives good crops of sugarcane, rice and wheat.
3) The Bhangar
The Bhangar is the older alluvium along the river beds forming terraces higher than the flood plain.The terraces are often impregnated with calcareous concretions known as "KANKAR".
Bhangar contains fossils of animals like rhinoceros, hippopotamus, elephants, etc.
4) The Khadar
The Khadar is composed of newer alluvium and forms the flood plains along the river banks.A new layer of alluvium is deposited by river flood almost every year.
This makes them the most fertile soils of Ganges.
