Reliance Industries will invest 1.7 billion dollars in a project in the US for extracting gas from shale, a sedimentary rock, in joint venture with US based, Atlas Energy Inc. Atlas Energy said it has reached an agreement with Reliance for the project in Marcellus, which spans parts of Pennsylvania, West Virginia, and New York, and could hold enough natural gas to satisfy US demand for a decade.Atlas said Reliance will acquire a 40 per cent undivided interest in about 300,000 acres of undeveloped leasehold held by Atlas. Shale gas is natural gas stored in organic rich rocks. Atlas Energy said in a press statement that Reliance will pay approximately 340 million dollars in cash upon closing, and an additional 1.36 billion dollars in the form of a drilling carry.