Question

describe different patterns of river in which they flow with the help of diagram

Answer 1

In geomorphology, drainage system us also know as river system these are the patterns formed by the streams, rivers and lakes in particular drainage basin.
The primary drainage patterns are ;

1.Dendritic

A dendritic drainage pattern is the most common form and looks like the branching pattern of tree roots. It develops in regions underlain by homogeneous material. That is, the subsurface geology has a similar resistance to weathering so there is no apparent control over the direction the tributaries take. Tributaries joining a larger stream at acute angle (less than 90 degrees).

2. Trellised

It is a rectangular shaped drainage pattern that develops where bands of rocks vary in resistance. In some areas there are alternate bands of hard and soft rocks. The flowing water can erode the soft rocks and thus flows along the bands of soft rock. Many such water channels form a trellis. The streams (called subsequent rivers) cut out the valleys (called vales) and join the main river (called Consequent River) at right angles. The main river, by sheer force, cuts the hard rock and flows down the slope forming an escarpment and thus a river gap is created.

3. Rectangular
A parallel drainage system is a pattern of rivers caused by steep slopes with some relief. Because of the steep slopes, the streams are swift and straight, with very few tributaries, and all flow in the same direction. ... All forms of transitions can occur between parallel, dendritic, and trellis patterns.

4. Radial
A Drainage pattern in which consequent streams radiate or diverge outward, like the spokes of a wheel, from a high central area; it is best developed on the slopes of a young, unbreached domal structure or of a volcanic cone.