UPSC Prelims 2013 Q63: Geography – Economic & Mineral Geography
Consider the following statements :
1. Natural gas occurs in the Gondwana beds.
2. Mica occurs in abundance in Kodarma.
3. Dharwars are famous for petroleum.
Which of the statements given above is/are correct?
- (a) 1 and 2
- (b) 2 only
- (c) 2 and 3
- (d) None
Answer: (b) 2 only
Explanation
Minerals and rock systems of India
| Statement | Verdict | Fact |
|---|---|---|
| 1. Natural gas occurs in the Gondwana beds | Incorrect | Gondwana rocks hold coal; natural gas and oil occur in Tertiary sedimentary rocks |
| 2. Mica occurs in abundance in Kodarma | Correct | Koderma, Jharkhand, was known as the mica capital of India |
| 3. Dharwars are famous for petroleum | Incorrect | Dharwar rocks hold metallic minerals: iron, manganese, gold, copper |
Rock systems and their minerals:
| System | Minerals |
|---|---|
| Dharwar | Iron ore, manganese, gold (Kolar), copper |
| Cuddapah and Vindhyan | Limestone, sandstone, diamonds (Panna) |
| Gondwana | About 98 percent of India's coal |
| Tertiary | Petroleum and natural gas (Assam, Gujarat, Mumbai High), lignite |
Answer: (b) 2 only.
Why each option is right or wrong
- (a) Incorrect. Natural gas does not occur in the Gondwana beds.
- (b) CORRECT. Only statement 2 is right: mica is abundant in Kodarma.
- (c) Incorrect. Dharwar rocks are known for metals, not petroleum.
- (d) Incorrect. Statement 2 is true, so 'None' is wrong.
Key point
Dharwar: metallic minerals. Gondwana: coal. Tertiary: petroleum and gas. Koderma (Jharkhand): mica.
Remember
Dharwar = metals; Gondwana = coal; Tertiary = oil.
Common mistakes
- Placing petroleum in ancient Dharwar rocks.
- Confusing Gondwana coal with natural gas.
- Forgetting that oil and gas need young sedimentary rocks.
Exam tip
Old hard rocks give metals; middle-aged rocks give coal; young rocks give oil and gas.
Sources
- NCERT Class XII — India: People and Economy (Mineral and Energy Resources)
- Geological Survey of India — Mineral resources of India