Analysis on relationship between coal structure and gas production quantity in deep coal seam of Yanchuannan Area at Southeast Ordos

According to the problems of the high depth,ultra low permeabity of the coal reservoirlow pressure co.eficient and geothermal radientcoalbed methane production slow occurred in No. 2 seam of Permian ShanxiFormation in Yanshuangnan Block at the Southeast edge of Ordos Basin.itfine description of the deep coal reservoir conducted on the great basic information of the block, based on the establishment of the coal structure standard quantitative divided with the logging curve,in combination with the observation of the parial ogging rock core,the coal structure of No.2 major seam inShanxiformation of Yanchuannan gas field was divided to the primary structure cal fractured structure coal and broken partical structure coal .According to the trial drainage production of the gas fel.,th fited diferent coal structure thickness found that the second crack of the fractured structure coal was developed,the permeability was good and the single well gas production was high.Among them the second crack developed zone with the t ickness of the broken structure coal more than1 m was the most favorable high production zone.T'he gas production effect of the sean was good and the sustainable and stable drainage could realize the area reduced,so as to improve the production of single wel.