Question

Consider the following statements with respect to drainage patterns;

1. The drainage pattern resembling the branches of a tree is known as “trellis”.
2. When the rivers originate from a hill and flow in all directions, the drainage pattern is known as ‘radial’.
3. When the primary tributaries of rivers flow parallel to each other and secondary tributaries join them at right angles, the pattern is known as ‘dendritic’.
4. When the rivers discharge their waters from all directions in a lake or depression, the pattern is know as ‘centripetal’.

Which of the above is/are correct?

1. 1, 2 and 4 only
2. 2 and 4 only
3. 2 and 3 only
4. 1, 2, 3 and 4

Answer 1

Correct Answer - Option 2 : 2 and 4 only

The correct answer is 2 and 4 only.

• The pattern of tributaries within a drainage basin depends largely on the type of rock beneath, and on structures within that rock (folds, fractures, faults, etc.)
  • Important Drainage Patterns
  • Radial Patterns
    • ​When the rivers originate from a hill and flow in all directions, the drainage pattern is known as ‘radial’. Hence, statement 2 is correct.
    • Volcanoes usually display excellent radial drainage.
    • The rivers originating from the Amarkantak range present a good example of it.
  • Centripetal Patterns
    • ​When the rivers discharge their waters from all directions in a lake or depression, the pattern is known as ‘centripetal’. Hence, statement 4 is correct.​

• ​Dendritic patterns
  • These are by far the most common, develop in areas where the rock (or unconsolidated material) beneath the stream has no particular fabric or structure and can be eroded equally easily in all directions.
  • The drainage pattern resembling the branches of a tree is known as “dendritic” the examples of which are the rivers of northern plain. Hence, statement 1 is NOT correct.
• Trellis drainage
  • When the primary tributaries of rivers flow parallel to each other and secondary tributaries join them at right angles, the pattern is known as ‘trellis’. Hence, statement 3 is NOT correct.
  • These patterns typically develop where sedimentary rocks have been folded or tilted and then eroded to varying degrees depending on their strength.
  • The Rocky Mountains of B.C. and Alberta are a good example of this, and many of the drainage systems within the Rockies have trellis patterns.