STUDY ON OCCURRENCE CHARACTERISTICS AND CONTROLLING FACTORS OF PERMIAN DEEP COALBED METHANE IN LINXING BLOCK

In order to implement the occurrence characteristics and controlling factors of Permian deep coalbed methane in Linxing block, the Permian coalbed methane in Linxing block was studied by means of core analysis and isothermal adsorption experiment. The occurrence characteristics of coalbed methane are studied from three aspects: chemical composition, distribution law and adsorption of coalbed methane. The results show that the Permian coalbed methane in Linxing block has good preservation conditions, and the gas content in the plane has the distribution law of "high in the west and low in the east". Isothermal adsorption parameters (Lander volume and Lander pressure) prove that Permian coalbed methane in Linxing block has broad prospects. The controlling factors of coalbcd methane occurrence arc studied from five aspects: geological structure, coal material composition, coal seam buried depth, hydrogcological conditions and surrounding rock properties of coal roof and floor. The results show that the occurrence of Permian coalbed methane in Linxing block is comprehensively affected by multiple factors, mainly controlled by structural conditions, hydrogcological conditions and surrounding rock properties of coal roof and floor.