摘要
Based on the research of the CO2 gas reservoir in the middle fault zone of Hailaer-Tamtsag Basin,the origin of CO2 was researched using the exclusive method by composition analysis of carbon,helium and argon isotope,data of CO2 amount and the research achievements of CO2 gas by the scholars.The results show that the average content of CO2 in the study area is more than 85%,and the value of the δ13CCO2 ranges from -13.1‰ to -8.8‰. With the characteristic of light δ13CCO2,the gas reservoir is the scarce one with a special isotopic composition.