Boreham, ChristopherEdwards, Dianne S.Hope, JanetChen, JunhongHong, Ziqing2015-12-080146-6380http://hdl.handle.net/1885/32233In severely biodegraded gases, every common C1-C5 hydrocarbon (methane, ethane, propane, iso-butane, n-butane, iso-pentane, n-pentane) and CO2 have been altered, negating the power of carbon and hydrogen isotopic compositions as correlation tools. Here, we show that neo-pentane (2,2-dimethylpropane) is recalcitrant, having an extreme resistance to biodegradation. In a gas biodegradation series with a common source from the Carnarvon Basin, Western Australia, the carbon and hydrogen isotopic compositions of neo-pentane provide the sole means by which a severely biodegraded gas can be correlated with a moderately biodegraded gas and a non-biodegraded gas. As such, the sterically hindered structure involving 2,2-dimethyl hydrocarbons can be exploited in gas (and oil) correlation studies. CrownKeywords: Carbon-and-hydrogen; Gas industry; alkane; biodegradation; carbon isotope; hydrocarbon; hydrogen isotope; natural gas; Australasia; Australia; Carnarvon Basin; Western Australia200810.1016/j.orggeochem.2008.06.0102015-12-08