Hyderabad: While the Krishna-Godavari offshore has already been identified as having shale gas potential, recent geological surveys have shown a larger tract of the Godavari-Pranahita basin to have significant shale gas potential.
Scientists say that surveys in pockets of the basin has shown that it is a prospective shale gas reserve but further studies will have to be carried out. The Oil and Natural Gas Corporation has already planned an expedition to ascertain its exact extent and potential.
Shale gas is a form of natural gas that is found trapped within pores of sedimentary shale rocks beneath the surface of the earth. With conventional sources of energy like coal and petroleum depleting fast, scientists are looking for other forms of fossil fuels. Shale gas, gas hydrates and coal methane are now considered potential sources of energy for the future.
Shale gas has been a huge success in the United States in recent times. Shale gas exploration in the country has been kicked off by institutes like the city-based National Geophysical Research Institute, ONGC and Directorate General of Hydrocarbons.
In the state, it is estimated that the Krishna-Godavari offshore basin has a prospective shale gas reserve of about 4340 square miles out of the basin area of 7800 square miles.
The Godavari-Pranahita basin, however, has a much larger area. Dr Kalachand Sain, senior principal scientist, NGRI, said, “Based on existing data and from surveys in some pockets of the Godavari-Pranahita basin, it is a prospective shale gas reserve and further studies are to be carried out to gauge the exact potential.”
If the prospects are high, it could come as a shot in the arm for our energy starved country. Along with the Pranahita basin, regions in upper Assam and Rajasthan have also been identified as potential targets.
ONGC has also planned more expeditions in these regions to assess the quantum of shale gas. Insiders say the industry is quite sure about the potential of shale gas in these regions.
However, there are many challenges in drilling shale gas. It requires an entirely different drilling technology than that used for conventional fuels. It's extraction requires horizontal drilling technology with huge amounts of water.
“It requires water in the range of billions of gallons. Plus the water gets highly contaminated and it can’t just be drained into rivers or on land. We need technology to recycle this water,” Dr Sain explained.
The ministry of petroleum and natural gas has already identified Cambay, Krishna-Godavari, Cauvery and Damodar basins as shale exploration targets.
Meanwhile, a recent policy brief by The Energy and Research Institute had cautioned about the potential issues that shale gas explorations could lead to.
