CAPF AC 2025 Q73: Geography – Physical Geography & Geomorphology
Which of the following types of mass movements are categorized as rapid movements?
1. Creep
2. Mudflow
3. Solifluction
4. Slump
Select the answer using the code given below.
- (a) 1 and 2
- (b) 1 and 3
- (c) 2 and 4
- (d) 3 and 4
Answer: (c) 2 and 4
Explanation
Rapid mass movements
How to think: mass movements are classed by speed.
Creep and solifluction are slow (centimetres in a year).
Mudflow and slump are rapid.
| Movement | Speed | Description |
|---|---|---|
| 1. Creep | Slow | Gradual downhill shifting of soil and debris |
| 2. Mudflow | Rapid | Water-saturated debris flows quickly down a slope |
| 3. Solifluction | Slow | Soil flows over frozen ground in cold regions |
| 4. Slump | Rapid | A mass slips down along a curved surface |
So statements 2 and 4 are rapid movements.
Answer: (c) 2 and 4.
Why each option is right or wrong
- (a) Incorrect. Creep (1) is a slow movement.
- (b) Incorrect. Creep (1) and solifluction (3) are both slow.
- (c) CORRECT. Mudflow and slump are rapid movements.
- (d) Incorrect. Solifluction (3) is slow.
Key point
Mass movements: slow (creep, solifluction), rapid (earthflow, mudflow, debris avalanche) and sliding (slump, debris slide, rockslide, rockfall). Triggered by water, slope and vibration.
Remember
Slow: creep, solifluction. Rapid: mudflow, slump.
Common mistakes
- Treating solifluction as rapid because it involves flow.
- Calling creep rapid because it happens everywhere.
- Leaving out slump, which is a quick slide.
Exam tip
Educated guess: anything with 'creep' or the slow freeze-thaw flow of solifluction is slow. That removes 1 and 3, leaving 2 and 4.
Sources
- NCERT Class XI Fundamentals of Physical Geography, Chapter 6 (Geomorphic Processes: mass movements)
- Savindra Singh, Geomorphology, chapter on Mass Movements