2016 · Q20
Which of the following statements relating to Dharwar geological system are correct?
- 1They belong to Archaean geological period.
- 2They are metamorphosed sedimentary rocks.
- 3They are of great economic importance for its mineral resources.
- 4They are found predominantly in Karnataka, Tamil Nadu, Odisha and Jharkhand.
Select the correct answer using the code given below:
indian-world-geographygeomorphology
- A1, 2, 3 and 4
- B2, 3 and 4 only
- C3 and 4 only
- D1 and 2 only
Explanation
All four statements are standard: the Dharwar system is grouped with the Archaean (GSI treats it as the first sedimentary system of the Archaean), it is a highly metamorphosed sedimentary rock system, it is economically important for iron ore, manganese, copper, lead, and gold, and it occurs predominantly in Karnataka, Tamil Nadu, Odisha, and Jharkhand. One published key gives (D) '1 and 2 only', but that option absurdly excludes the unambiguously true statements 3 and 4; three other reputable keys agree on (A).