Pressure transient characteristics of a fractured horizontal well in shale gas reservoirs

Abstract

Shale gas reservoirs have extremely low matrix permeability and complicatedly-distributed natural fractures. Because of ultralow permeability, they have a significantly long period of transient flow. The pressure transient response for a horizontal well with transverse multiple fractures is controlled by many of important fracture properties and nonlinear flow processes. This paper presents a comprehensive reservoir simulation model to investigate the characteristics of pressure transient responses under the influences of hydraulic fracture properties and nonlinear gas flow mechanism. Factors considered in this study include the number of hydraulic fractures, fracture half-length, fracture spacing, non-Darcy flow, and adsorption under reservoir flow condition as well as skin effect. Results from the numerical simulations showed various flow periods in log-log plots of pseudo-pressure and derivative of pseudo-pressure versus time. This study provides insights into the pressure transient characteristics of a hydraulically fractured horizontal well under realistic scenarios of shale gas production.