Flow2Quake, an integrated multiphase flow, geomechanical and seismicity model for efficient forecasting of injection and extraction induced earthquakes

Abstract

Efforts to secure and decarbonize the energy sector are driving various subsurface reservoir operations. These operations carry a risk of inducing surface deformation and earthquakes. To assess these risks, modeling tools integrating fluid flow, geomechanical and seismicity modeling are needed. Here, we demonstrate the use of an efficient Vertical Flow Equilibrium (VFE) multiphase fluid flow model in an integrated framework for deformation and seismicity modeling both under fluid extraction or injection configurations. The VFE-computed spatio-temporal pressure evolution is fed to a geomechanical module to compute surface deformation and stress changes in and around the reservoir. Stress changes feed a seismicity module to calculate earthquake probabilities. First, we apply the benchmarked model to gas extraction from Groningen. There, we can reduce the variance of pressure measurements by $\sim$38% with respect to a pre-existing single phase flow model while remaining computationally efficient. The surface deformation and seismicity simulations show remarkable agreement with observed data. Second, we study induced seismicity due to CO${}_2$ sequestration in the Decatur phase 1 project. We find that, for the Decatur phase 1 project, poroelastic stress changes can account for most of the non-clustered observed seismicity within modeling uncertainties. Finally we simulate scenarios for CO${}_2$ sequestration using the Quest field. The sloping reservoir topography significantly impacts the predicted position of the CO${}_2$ plume but the effects on geomechanical deformation (and seismicity) are minimal. Incorporating VFE models with geomechanical and seismicity forecasts with real-world case applications can allow real-time hazard assessment and mitigation procedures.