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Geography · Continental Drift & Seafloor Spreading

UPSC Prelims 2025, Question 25

The concept being tested: Continental drift evidence (matching rock formations, mineral deposits, sediment systems).

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.

Options

  1. AI and III only
  2. BI and II only
  3. CI, II and IIICorrect answer
  4. DII and III only

The answer: I, II and III

Continental drift, proposed by Alfred Wegener, is supported by several independent lines of evidence, and all three statements listed are genuine, textbook-recognised proofs of it. Rock correlation: the ancient rock belt along the Brazilian coast matches in age and composition with the rock belt of Western Africa, showing the two coasts were once joined. Mineral correlation: the gold deposits of Ghana correspond to the gold-bearing rocks of the Brazilian plateau, a match explainable only if the two continents once lay side by side. Sediment correlation: the Gondwana system of India — glacial tillites and coal-bearing beds — has recognised counterparts across six landmasses of the Southern Hemisphere, including South Africa, South America, Australia and Antarctica, confirming they once formed a single Gondwanaland. Because all three evidences are independently valid, the correct answer includes all three statements.

What UPSC was testing

The 'all three correct' framing is the trap here — candidates instinctively look to eliminate at least one statement, especially the less familiar gold-deposits detail, but UPSC drew all three from the standard evidence list for continental drift, so full familiarity with rock, mineral and sediment correlation together (not just coastline fit) was needed.

How often this comes up

This concept has appeared 3 times in UPSC Prelims General Studies Paper I between 2015 and 2025 — in 2018, 2023 and 2025.

The option-by-option autopsy for this question — why each of the other three is wrong, and which neighbouring concept each one was built from — is in the app.