Question

Define the term 'drainage'. Describe different drainage patterns.

Answer 1

The term `drainage' describes the river system of an area. The streams within a drainage basin (the area drained by a single river system) form certain patterns which are given below:
(i) Dendritic pattern: The dendritic drainage pattern develops where the river channel follows the slope of the terrain. The stream with its tributaries resembles the branches of a tree, thus the name dendritic.
(ii) Trellis: This drainage pattern develops when a river is joined by its tributaries at approximately right angles. This drainage pattern also develops where hard and soft rocks exist parallel to each other.
(iii) Rectangular: This drainage pattern develops on a strongly jointed rocky terrain.
(iv) Radial Pattern: This drainage pattern develops when streams flow in different directions from a central peak or a dome like structure.