Pore pressure evolution in media with isotropic and anisotropic permeability - analytical and numerical solutions

Understanding perturbations caused by underground fluid injection and extraction is essential for steady long-lasting operations of subsurface energy systems (e.g. geothermal systems). The systems are often too complex to obtain precise analytical solutions and computationally expensive to have fine numerical results. Simplified settings give the benefit of understanding the role of driving geological parameters as well as examining the limits of each approach. In this study, we focus on the influence of permeability on pore pressure and present analytical and numerical solutions of spatial and temporal evolutions of pore pressure in an elastic homogeneous porous media with isotropic and anisotropic permeabilities. We use COMSOL Multiphysics to build a 3D finite element model with injection/production wells and investigate where the numerical solutions of the spatially limited volume coincide and diverge from corresponding analytical solutions of pore pressure in infinite media.