Methane in aquifers and alluvium overlying a coal seam gas region: Gas concentrations and isotopic differentiation

Geological Control Mechanism of Coalbed Methane Gas Component Evolution Characteristics in the Daning-Jixian Area, Ordos Basin, China

“…19−21 The source of methane in the aquifer overlying the reservoir was obtained from CBM gas concentrations and isotopic differentiation. 22 A kinetic model of methane carbon isotope fractionation can be constructed to evaluate the CBM content and determine the stage of CBM extraction. 23 δ 13 C 1 values can also be used to explain the mechanism of the influence of flowing groundwater in coal seams on CBM carbon isotope fractionation phenomena.…”

“…It is of great significance to investigate the desorption–diffusion–transport process of CBM in the regional geological context by studying the gas components of CBM. − The geochemical characterization of CBM is an important means to study the type of CBM genesis and gas transport characteristics. , CH 4 undergoes isotopic fractionation due to desorption and diffusion during transport in porous media coal beds . Currently, a great deal of research has been conducted on isotopic fractionation after CBM generation, especially during CBM transportation processes (including primary/secondary migration, uplift and dissipation, core degassing, and gas well production). − The source of methane in the aquifer overlying the reservoir was obtained from CBM gas concentrations and isotopic differentiation . A kinetic model of methane carbon isotope fractionation can be constructed to evaluate the CBM content and determine the stage of CBM extraction .…”