Q1. [2] deep thorough-understanding
The Krishna-Godavari basin has emerged as a significant new source of natural gas along India's east coast. Given that petroleum occurrences are associated with anticlines and fault traps in tertiary rock formations, what does the discovery of gas in this basin suggest about its underlying geological structure?
Generated by claude-sonnet-4-6 · 2026-06-26 13:34 · grounding rag
Model Answer
The discovery of natural gas in the Krishna-Godavari basin suggests that the region contains tertiary age rock formations with structural traps such as anticlines (upfolds/domes) or fault traps. Since gas is lighter than oil and occurs above it in such formations, the basin likely has porous limestone or sandstone layers capped by non-porous rocks, creating conditions suitable for hydrocarbon accumulation.
Source: Conventional Sources of Energy (Petroleum & Natural Gas), Chapter 5
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Explanation
- The question links two facts from the textbook: (1) petroleum/gas occurs in anticlines and fault traps in tertiary rock formations, and (2) Krishna-Godavari basin has new gas reserves.
- Your answer must connect the discovery to the geological implication — tertiary rocks with structural traps.
- Mention that gas sits above oil (lighter) — this shows understanding of the trap mechanism.
- Don't write more than 50–60 words; examiners award marks for these two key points.