The characteristics of rock fluid occurrence in oil-gas layer of coal seam roof based on pore structure characterization
The effect of pore structure characteristics on the occurrence of oil and gas in the roof sandstone of Yan'an Formation of coal seam in Fuxian mining area of Ordos Basin is discussed based on the results of cast thin section,SEM and NMR experiments.The results show that the size distribution of pore-throat in Yan'an Formation sandstone is wide and bimodal.Residual intergranular pores and solution pores form a large pore throat system,while intergranular pores form a small pore throat system.Pore throat volume and connectivity are the key factors affecting the occurrence of oil and gas in the sandstone.