Effective Sand Scale Evaluation of Tight Sandstone Gas Reservoirs Based on Production Performance Constraints

Effective sand body size is the key to well location selection, well pattern optimization and residual reserve evaluation of gas reservoir. Tight gas reservoirs have strong heterogeneity and high uncertainty of sand body spatial distribution characteristics. The reservoir fine description method based on structural characterization and sedimentary facies constraint has a large deviation and low static and dynamic consistency for complex gas reservoirs with small channel scale, multiple phases and rapid migration. Based on the detailed geological description, combined with the gas reservoir engineering method, the production dynamic analysis and monitoring results such as interference test, formation pressure, discharge area and gas production profile are applied to verify or feedback the connectivity of sand bodies in plane and vertical, and the key parameters such as effective sand body distribution range, sand body size and direction are constrained according to the distribution characteristics of gas well discharge area. Effective sand body distribution is defined by dynamic and static combination. Thus, an effective sand body size evaluation method is established to improve the reliability of effective sand body characterization, and provide a basis for well location deployment, reserve evaluation and development adjustment of complex tight gas reservoirs.