A Reservoir and Geomechanical Coupling Simulation Method: Case Studies in Shale Gas and CBM Reservoir

To investigate the time-lapse, three-dimensional (so-called four dimensional/4D) stress during production/injection, a 4D multi-physical modeling method is proposed. A finite difference method (FDM) reservoir simulator is used to couple thermal-hydrological-chemical (THC) processes, while a finite element method (FEM) geomechanical simulator takes on the role of a thermal-hydrological-mechanical (THM) coupling calculator. Heterogeneity and anisotropy of the reservoir flow and geomechanical properties as well as the permeability stress-sensitivity can be considered in modelling based on field and experimental data. In order to couple the flow model with the geomechanical model, an improved interface (coupling) Python code is provided to communicate data between the finite difference (FD) and finite element (FE) grids. Ultimately, this method is applied to analyze the stress and poro-elastic parameters evolution of hydraulic fractured Sichuan Basin shale gas reservoir and Qinshui Basin coalbed methane (CBM) reservoir in production.