Based on the geological research of Kelasu structural belt in Kuqa depression, we analyze tight sandstone gas reservoir properties of Dabei area by using microscope and laser scanning confocal microscope (LSCM) observation, mercury-injection capillary pressure (MICP) testing, and porosity and permeability testing. The results show the followings. The major pore types in tight sandstone gas reservoirs of Dabei area are slot pores and solution pores; Expulsion pressure of tight sandstone in the study area is generally above 5 MPa, with poor pore sorting and small pore throat radius; When the sandstone reservoir porosity is less than 5%, the correlation between porosity and permeability is weak, with small porosity and high permeability, which may be resulted from the contribution of micro-fractures in tight sandstone. The major rock type in Dabei gas field is feldspar lithic quartz sandstone, and it is dominated by calcite cementation. Besides, tight sandstone reservoir shows obvious fractures reconstruction.

tight sandstone gas  /  reservoir properties  /  pore structure  /  Kuqa-depression