Porosity, Permeability And Favorable Production Region Of Coal Reservoirs In Gujiao Block, Xishan

Gujiao mining area in Xishan has a strong business development potential of coalbed methane(CBM). Yet not enough cognitions on coal reservoir heterogeneity has been concluded. Consequently, the CBM commercial-scale development is difficult to support. On this research, we firstly mastered the geological structure background. And then combining the method of poroperm physical simulation on high temperature and pressure and the geothermal and the simulation result of geostress, we built the permeability prediction model corresponding to geological conditions. The prediction model was used to predict the 3D space distribution characteristics of porosity and permeability. Then combined the poroperm characteristic under Atmospheric Pressure and Temperature, and divided Gujiao mining area into six porosity and permeability geological units. At the same time, the geological factors and control mechanism that affect porosity and permeability was discussed. At last, some exploitation suggections has been put forward for different units. We concluded that: Tunlan Mining Area has higher permeability, better reservoir connectivity and poorer heterogeneity, is the most favorable production blocks and should give priority to exploit. The Dongqu Mining Area has higher quantitative of pore and fracture and better permeability, but the coal structure is seriously crushing and producing much coal pulverized coal particles and filling the fissure space, hindered the seepage of CBM, therefore eliminating the pulverized coal in the process of production is important. The permeability of Malan, Zhenchengdi and Xiqu Mining Area is in the medium level, the quantitative of pore and fracture is relatively lower. So the fracturing technology is necessary in the process of production. The unexploited areas, Ximing and Duerping Mining Area has poorer permeability, so the fracturing technology is necessary.