关键词: 寿阳区块, 煤层气开发, 深部煤储层, 渗透率, 地应力, 游离气

Abstract: Qinshui Basin is the main CBM basin in China, and its deep coalbed methane has become the main object of CBM development in the future., In view of the insufficient understanding of deep CBM reservoir of the basin and the lack of targeted measures for development ,taking Shouyang block in the north of Qinshui Basin as the research area and coal 15 as the research object, the geological particularity and development countermeasures of deep CBM are discussed. Coal seam 15 is basically stable, the thickness is basically about 3m, and the thickness scale is controlled by sedimentary environment and sedimentary facies. Most of the gas content is between 10 ~ 12 m3/t, and it is affected by the buried depth and the degree of metamorphism. After the critical point appears at the buried depth of about 1200~1500m, the gas content gradually decreases with the increase of depth. Different from the "three high" characteristics in other deep areas, the deep reservoir of coal seam 15 is characterized by low pressure, high stress and medium temperature, which belongs to the category of serious low pressure gradient and geothermal gradient. The permeability is classified as high porosity and low permeability, and the permeability is generally 0.01 ~ 0.1mD. The permeability is mainly affected by the buried depth of coal seam, in-situ stress, coal structure and coal pore characteristics. According to the low moisture content, high porosity and gas production characteristics of production wells of coal seam 15, it is considered that coal seam 15 may have a high proportion of free gas content. Based on the geological particularity of CBM and the current situation of development technology at home and abroad, the countermeasures and suggestions for CBM development mode and key processes are put forward, that is, the segmented fracturing mode of horizontal well in roof rock stratum or the method of multi branch horizontal wells in surrounding rock can be used when developing coal seam 15 alone, which has made a breakthrough in gas production at 15 coal in the southern basin.The vertical well mode of surrounding rock and coal seam combined pressure can be used when developing multi coal seams, the corresponding suggestions on increasing production and drainage technology are put forward.