the west. The average width of these plains varies between - km. The maximum depth of alluvium deposits varies between , - , m. From the north to the south, these can be divided into three major zones: the Bhabar , the Tarai and the alluvial plains.
The alluvial plains can be further divided into the Khadar and the Bhangar . Bhabar is a narrow belt ranging between - km parallel to the Shiwalik foothills at the break-up of the slope. As a result of this, the streams and rivers coming from the mountains deposit heavy materials of rocks and boulders, and at times, disappear in this zone. South of the Bhabar is the Tarai belt, with an approximate width of - km where most of the streams and rivers re-emerge without having any properly demarcated channel, thereby, creating marshy and swampy conditions known as the Tarai .
This has a luxurious growth of natural vegetation and houses a varied wild life. The south of Tarai is a belt consisting of old and new alluvial deposits known as the Bhangar and Khadar respectively. These plains have characteristic features of mature stage of fluvial erosional and depositional landforms such as sand bars, meanders, ox- bow lakes and braided channels. The Brahmaputra plains are known for their riverine islands and sand bars.
Most of these areas are subjected to periodic floods and shifting river courses forming braided streams. The mouths of these mighty rivers also form some of the largest deltas of the world, for example, the famous Sunderbans delta. Otherwise, this is a featureless plain with a general elevation of - m above the mean sea level. The states of Haryana and Delhi form a water divide between the Indus and the Ganga river systems.
As opposed to this, the Brahmaputra river flows from the northeast to the southwest direction before it takes an almost ° southward turn at Dhubri before it enters into Bangladesh. These river valley plains have a fertile alluvial soil cover which supports a variety of crops like wheat, rice, sugarcane and jute, and hence, supports a large