In which of the following regions of India are shale gas resources found? 1. Cambay Basin 2. Cauvery Basin 3. Krishna-Godavari Basin Select the correct answer using the codes given below:

The answer is D, because all three basins have been identified as shale gas prospects. Shale gas is natural gas trapped in fine-grained, organic-rich shale rock, and it is produced by hydraulic fracturing, so the key question is where the right source rock and maturity exist.

• Cambay Basin (Gujarat): Tertiary shales here are a recognised shale gas prospect, and ONGC has drilled exploratory shale gas wells in the basin.
• Cauvery Basin (Tamil Nadu): Shale gas potential has been assessed in the Cauvery onshore area, so statement 2 is correct.
• Krishna-Godavari Basin (Andhra Pradesh): Gondwana and Permian-age shales in the KG basin are a known shale gas target, so statement 3 is correct.

Students often recall that shale gas is India's new frontier, but the official list of prospective basins is wider than the three named here, including Damodar, Assam-Arakan and Indo-Gangetic. For Mains GS-III (energy security and unconventional hydrocarbons), the policy point is that India has not yet started commercial shale gas production, and the environmental concerns around fracking are still a live debate.

Trap: Candidates tend to pick A or C by remembering only the offshore or well-known conventional basins. Check each basin against the shale gas assessments rather than the conventional oil and gas map.