Keywords: 
• coal-type gas /
• thermal simulation /
• carbon isotope

Abstract: Through research of gaseous hydrocarbon geochemistry of thermal simulating experiment and productive gaseous matter of nature evolution process from coal- measure source rocks, author think changeable of methane carbon isotope (δ¹³C₁) are been from light t weight along with add of degrees in course thermal evolution of coal-measure source rocks. The changeable range of ethane carbon isotope(δ¹³C₂) are rather narrow from-28.3‰ to-20‰(PDB). δ¹³C₂ value ware-28‰±(Ro=0.45%-0.65%)is the lower thermal evolution stage of coal-measure source rocks, when the rocks ware getting into mainly hydrocarbon-generating stages (Ro=0.6%-1.5%)δ¹³C₂ value of the gases are generally distributed -26‰ - -23‰,along with going step further evolution of the rocks,ethane carbon isotope ware gradualty got weight and δ¹³C₂ vaice or generally large than -20‰. It is not the only characteristics of mixed-source gathered of differentially stem from gases that partial opposites sequence of the carbon isotope,on condition that specified styles of organisic,hydrocarbon source rocks have to from for its oneself vcolution.On the lower evolution stages of the rocks,it is mainly may decided by organic mather-source that gaseous hydrocarban carbon isntope are crccLlrrdr: features of partial opposites seqence and ethane carbon isotope value relatively lower,the features are related to geochemical compositions of primary soluble organic matter.