Natural gas before the natural gas can be transported. Natural gas extracted from oil wells is called casinghead gas (whether or not truly produced up the annulus and through a casinghead outlet) or associated gas. The natural gas industry is extracting an increasing quantity of gas from challenging resource types: sour gas, tight gas, shale gas, and coalbed methane. There is some disagreement on which country has the largest proven gas reserves. Sources that consider that Russia has by far the largest proven reserves include the US CIA (47 600 km³), the US Energy Information Administration (47 800 km³), and OPEC (48
Natural gas in Qatar Natural gas in Qatar The natural gas in Qatar covers a large portion of the world supply of natural gas. According to the "Oil & Gas Journal", as of January 1, 2011, reserves of natural gas in Qatar were measured at approximately ; this measurement means that the state contains 14% of all known natural-gas reserves, as the world's third-largest reserves, behind Russia and Iran. The majority of Qatar's natural gas is located in the massive offshore North Field, which spans an area roughly equivalent to Qatar itself. A part of the world's largest non-associated, natural-gas field, the North Field,