Geomechanical modeling of injection-induced seismicity: Critical perspectives for a safe and sustainable geoenergy transition

Injection-induced seismicity from subsurface fluid injections has risen sharply over the past two decades, prompting public concern and mitigation measures such as microseismic monitoring and traffic-light systems (TLSs). As the energy transition accelerates, large-scale injection activities in geothermal reservoirs, CO2 sequestration sites, and underground hydrogen storage are expanding. Although essential to achieving net-zero goals, these operations increase seismic risk, underscoring the need for predictive geomechanical modeling. This paper reviews the documented mechanisms of injection-induced seismicity and critically examines the physicsbased models developed to simulate these processes. Physics-based modeling plays an essential role because it offers mechanistic insights that neither laboratory experiments nor field observations can provide alone. Field observations provide information on event magnitudes and hypocenter locations, while laboratory experiments constrain frictional behavior at the sample scale. Numerical modeling, however, uniquely provides detailed views of the co-evolution of stress, pore pressure, and slip across entire fault systems over the full course of the injection sequence. While pressure-diffusion models offer simplicity for real-time applications, they fail to capture key coupled processes such as thermoelastic and poroelastic stresses. Advances in computational power have enabled more sophisticated coupled models; however, many still rely on simplified geometries that poorly represent geological layering and fault topographies. Most also assume single-phase flow, even as CO2 and hydrogen injection projects demand multiphase simulations. Furthermore, these models inherit numerical limitations that constrain their predictive power. By analyzing key parameters controlling model performance and challenges in current forecasting frameworks, this review provides a state-of-the-art synthesis and outlines opportunities for developing robust, multi-physics approaches to support safe and sustainable geoenergy operations.