New Delhi, Feb 6 : Oil India has sought permission from the government to hunt for shale oil and gas in several of its blocks in Arunachal and Assam.
At least two of the PSU's blocks in Arunachal Pradesh - Deomali and Jairampur - and three in Assam - Chabua, Dibrugarh and Dumduma - hold potential.
The Union cabinet has already approved the ministry of petroleum and natural gas's proposal to allow state-run oil and gas firms to hunt for shale oil and gas in their existing acreages.
Top officials said Oil India believed Dishang Shales in the 120-sq-km Deomali tract alone could prove to be a major find for the company.
Indian engineers have gathered experience on fracking - the technology to find shale gas - by spending time in the US and are now able to hunt for the scarce resource on their own. Fracking technology sends high pressure streams of water, sand and chemicals into shale formations to bring up the oil and gas.
A former Oil India chairman C. Ratnam has for long advocated that India exploit its shale reserves in Arunachal, which some experts estimate to be up to 14 billion tonnes.
In fact, there has even been speculation that part of China's renewed interest in Arunachal is linked to shale reserves.
The Dishang trap extends northwards from Tirap district of Arunachal towards Kohima and possibly Manipur.
Exploratory drilling had found shale in Arunachal Pradesh and Nagaland, but Oil India did not feel they were viable. However, the latest find could be the "big one", say company officials here.
However, most of the exploration area in Arunachal is inside virgin forests and on young hill formations. Environmentalists have objected to fracking because of the damage to forest cover and possible contamination of ground water.
Indian geologists have identified some 28 basins for shale gas exploration. They dispute US Energy Information Administration figures, which place the reserves at 96 trillion cubic feet (tcf).
One estimate by Indian scientists places potential reserves at as high as 527 tcf.
Initial finding shows shale reserves in the east, Northeast and the western states, including Gujarat and Bengal, besides isolated pockets in central India. Last year, ONGC and Oil India had identified 56 shale gas blocks that have the potential to be explored after the Centre cleared a much awaited shale oil and gas policy. ONGC had identified 50 blocks and OIL 6.
"Under the first phase of assessment of shale gas and oil, exploration and exploitation, at present, 56 petroleum exploration lease/petroleum mining lease blocks have been identified by the national oil companies," the oil ministry had said.