Question

Which of the following statements accurately describes the upper or mountain course of a river?

1. The water flows slowly through a wide valley with stable banks.
2. The river has significant erosive power, capable of moving large stones.
3. Angular stones are smoothed into rounded pebbles by friction.
4. The river primarily deposits silt and mud in this stage.

• A. All
• B. ii, iii
• C. ii only
• D. iii only

Answer 1

Answer:

B. ii, iii

THE UPPER OR MOUNTAIN COURSE

• Here the water is fast flowing and runs through a 'V' shaped valley with unstable banks.

• The fast flowing water has great erosive powers, particularly after rains, being able to move large stones and roll them along.

• Angular stones washed into the river are rubbed against one another, to form rounded pebbles.