UPSC Prelims 2014 GS Paper I · Q38 of 100 General Science medium

With reference to two non-conventional energy sources called 'coalbed methane' and 'shale gas', consider the following statements : 1. Coalbed methane is the pure methane gas extracted from coal seams, while shale gas is a mixture of propane and butane only that can be extracted from fine-grained sedimentary rocks. 2. In India, abundant coalbed methane sources exist, but so far no shale gas sources have been found. Which of the statements given above is/are correct?

  1. (a) 1 only
  2. (b) 2 only
  3. (c) Both 1 and 2
  4. (d) Neither 1 nor 2 ✓ UPSC's answer

Why the answer is (d)

• Statement 1 is wrong: coalbed methane is mostly methane with some other gases, and shale gas is also predominantly methane (with ethane, propane and butane), not 'propane and butane only'.

• Statement 2 is wrong: India has identified shale gas resources in the Cambay, Krishna–Godavari, Cauvery, Assam–Arakan and Gondwana basins, alongside CBM in Jharkhand, West Bengal and Madhya Pradesh.

• Hence neither 1 nor 2, option (d).

Why the other options are wrong

(a) 1 only
Statement 1 is wrong: shale gas is mainly methane.
(b) 2 only
Statement 2 is wrong: India has shale gas resources.
(c) Both 1 and 2
Both statements are wrong.

Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2014, held on 24 August 2014. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

Reading the answer is not the same as getting it right under a clock. Practise this question with UPSC's negative marking, and anything you miss goes into an error notebook until you get it right twice.

Practise this paper free