Project

Geothermal energy is an important component of the transition to a low-carbon energy system. However, the development of enhanced geothermal systems (EGS) is challenged by induced seismicity caused by high-pressure fluid injections used to increase subsurface permeability. A key hazard management strategy is to stop injection and sometimes depressurize the reservoir when seismic activity exceeds predefined thresholds. Yet earthquakes often continue after injection stops, and the strongest events may occur during this period, known as trailing seismicity. Understanding and controlling trailing seismicity is essential for improving the safety and reliability of geothermal projects. 

Existing statistical and numerical studies have attempted to predict and explain trailing seismicity, but results remain inconclusive because they rely mainly on injection and seismicity data, while direct observations of pressure propagation and deformation are limited. To address this gap, we propose a series of controlled hydraulic stimulation experiments at the BedrettoLab. Its dense pressure and deformation monitoring network provides a unique opportunity to observe the hydromechanical processes that drive trailing seismicity. 

Combining these experiments with advanced numerical modelling will improve understanding of the mechanisms controlling trailing seismicity, evaluate the influence of shut-in protocols and fracture properties, and assess the relevance of findings for full-scale geothermal operations. The project aims to enhance predictive models and develop optimized shut-in strategies that reduce seismic risk and support wider deployment of geothermal energy. 

Project Contact

Valentin Gischig

Partners

Jordan Aaron
Stefan Wiemer
Ryan Schultz

Funding

Swiss National Science Foundation