May 17, 2012. Oil & Natural Gas Corp. (ONGC) of India and competitors may drill for at least four years before producing the first commercial shale gas in the nation as China expects to commence output next month and Australia boosts reserves. ONGC, India's biggest explorer, is studying data for shale- gas deposits and awaiting a government policy on commercial drilling for gas trapped in shale rock. China Petrochemical Corp. will start pumping the nation's first shale gas from a project in Sichuan province next month. Companies from France's Total SA to Australian mining giant BHP Billion Ltd. began shale-gas projects around the world after a surge of production in the U.S. turned that fuel-importing nation into the world's biggest producer of natural gas. The U.S. produced 96 billion cubic meters in 2009, overtaking Russia as the largest provider of the fuel. Australia's energy minister Martin Ferguson said that nation is likely to possess enough shale gas to double its total gas resources and add to 184 years of output, while China is estimated to hold the world's largest deposit of the unconventional fuel. India holds 6.1 trillion cubic feet of technically recoverable shale gas reserves in three basins. That was less than 10 percent of the 63 trillion cubic feet estimate made the previous year, in April. ONGC found shale gas at a well in India's West Bengal state. The company signed an agreement with ConocoPhillips (COP) for developing shale resources in India and North America. India has started mapping its shale resources and will have exploration rules in place by 2013, Prime Minister Manmohan Singh said. Blocks will be auctioned next year after the policy is published.