Abstract:
Based on stable organic carbon isotopic analysis for 24 coal sample and 12 gas samples from six coal seams in Qidong coal mine, Huaibei coalfield, the paper has studied distribution characteristics and variation trend of the coal and gas carbon isotope, providing the theoretical basis for the analysis of different coal seams and gas sources. The study shows:Variation range of
δ13C is -22.76‰~-25.11‰.
δ13C value in coal seams 6-1 to 9 presents undulated variation, probably influenced by the coal depositional environment; Variation range of methane
δ13C
1 is -52.51‰~-63.65‰, The variation range of
δ13C
1 is characterized by containing secondary biogenic gas. And the CO
2 carbon isotopic values (-22.61‰~-17.96‰) demonstrated that CO
2 in methane was resulted from coal pyrolysis.