大宁—吉县区块深部煤层气富集主控因素分析及地质工程甜点区评价OA北大核心CSTPCD

Accurate evaluation and reasonable selection of geological engineering dessert areas for coalbed methane are the basis for de-tailed formulation of integrated exploration and development plans of coalbed methane.Through in-depth analysis of coal core descrip-tion,chemical analysis,logging,seismic data,and development dynamics of the 8# coal seam in the deep Carboniferous Benxi Formation of the Daning-Jixian block,the main controlling factors of deep coalbed methane enrichment were discussed from the aspects of the roof and floor lithology and thickness of coal seam,structure,sedimentary environment,and coal rock characteristics.The evaluation criteria for geological and engineering sweet areas were established,and the geological engineering sweet spot areas in the study area were fur-ther divided.The research results indicate that the enrichment of coalbed methane is mainly influenced by the roof and floor lithology,structure and coal rock characteristics,and the influence of sedimentary environment on coalbed methane enrichment is mainly reflected in the combination and sealing characteristics of the roof and floor rock.According to evaluation result,in the study area,there are geo-logical class Ⅰ-engineering class Ⅰ favorable area of 411.5 km2,with a resource volume of 1 038.75 × 108 m3,geological class Ⅱ-engi-neering class Ⅰ favorable area of 596.2 km2,with a resource volume of 1 192.4 × 108 m3 and the geological class Ⅱ-engineering class Ⅱfavorable area of 287.4 km2,with a resource volume of 574.5 × 108 m3.