摘要
Extensive investigation on geochemical characteristics, origin and source of H2S-rich natural gas in the northeastern Sichuan Basin was processed and abundant documentation was accumulated in resent years. The correlations between the content of hydrogen sulphide and the components of hydrocarbons, the carbon isotopic compositions of methane, ethane and carbon dioxide indicate that the H2S-rich natural gases reservoir in the Feixianguan and Changxing Formations of the northeastern Sichuan Basin are the product of oil cracking under the catalysis of sulphate and possibly derived from the Silurian source rocks; and that the generation of 13C-riched CO2 in the H2S-rich natural gas is related to the reduce of H2S content in natural gas and is the result of H2S corrosion on reservoir carbonate.