Nonlinear diffusion-based Interpretation of Hydraulic Fracturing Induced Seismicity

We present a microseismicity-based approach to characterise the hydraulic transport during borehole fluid injections. This approach allows to reconstruct the enhanced permeability evolution inside of the stimulated rock. We apply our approach to seismicity recorded during a hydraulic fracturing treatment in the Barnett Shale. The spatio-temporal analysis of induced events reveals a significant nonlinear fluid-rock interaction. To explain this, we consider an effective poroelastic medium representation. We suppose a nonlinear diffusional relaxation of the pore-pressure perturbation with a power-law pressure-dependence of permeability. We generate synthetic seismicity distributions whose spatio-temporal features are similar to the ones which we observe in Barnett Shale. Our results indicate that the fluid transport during the hydraulic fracturing treatment can be described by a nonlinear diffusion based on a power-law dependent permeability.