UPSC Prelims 2025 Q25: Geography – Physical Geography & Geomorphology
Which of the following are the evidences of the phenomenon of continental drift?
I. The belt of ancient rocks from Brazil coast matches with those from Western Africa.
II. The gold deposits of Ghana are derived from the Brazil plateau when the two continents lay
side by side.
III. The Gondwana system of sediments from India is known to have its counterparts in six
different landmasses of the Southern Hemisphere.
Select the correct answer
using the code given below.
- (a) I and II only
- (b) I and III only
- (c) I, II and III
- (d) II and III only
Answer: (c) I, II and III
Explanation
Evidence for Continental Drift (Alfred Wegener, 1912)
| Evidence | What it shows | Listed? |
|---|---|---|
| Jig-saw fit | South America and Africa coastlines match (Bullard, 1964, at 1,000 fathoms) | Not in this question |
| Rocks of same age across oceans | 2,000-million-year-old rock belts of the Brazil coast match West Africa | Statement I — yes |
| Tillite | Glacial deposits of Gondwana found in India, Africa, Australia, Antarctica, South America, Madagascar | Statement III — yes |
| Placer deposits | Gold of the Ghana coast has no source rock there; it came from the Brazil plateau when the two were joined | Statement II — yes |
| Fossils | Mesosaurus in South Africa and Brazil; Glossopteris across Gondwana | Not in this question |
All three statements are standard NCERT evidences of drift.
The Gondwana system has counterparts in six landmasses of the Southern Hemisphere.
Answer: (c) I, II and III.
Why each option is right or wrong
- (a) Incorrect. This leaves out the Gondwana tillite evidence (III), one of Wegener's strongest proofs.
- (b) Incorrect. It leaves out the placer gold of Ghana (II), which NCERT lists as drift evidence.
- (c) CORRECT. Matching rock belts, Ghana's placer gold and Gondwana sediments all point to joined continents.
- (d) Incorrect. It leaves out the Brazil–West Africa rock belt match (I).
Key point
Drift evidences (NCERT): jig-saw fit, same-age rocks, tillite, placer deposits, distribution of fossils.
Remember
Ghana's gold came from the Brazil plateau — placer evidence of continental drift.
Common mistakes
- Rejecting the Ghana gold statement as odd; NCERT names it as the placer deposit evidence.
- Thinking the Gondwana system exists only in India; its counterparts are in six southern landmasses.
- Confusing continental drift evidence with plate tectonics evidence like sea-floor spreading and palaeomagnetism.
Exam tip
Remember 'J-R-T-P-F': Jig-saw fit, Rocks, Tillite, Placer deposits, Fossils — NCERT's five proofs of drift.
Sources
- NCERT Class XI — Fundamentals of Physical Geography, Ch 4 (Distribution of Oceans and Continents)
- Alfred Wegener — The Origin of Continents and Oceans (1915)