Faults and fractures are fundamental structural features of reservoirs and sealing units, with hydraulic and mechanical properties that differ markedly from the surrounding rock. Their behaviour governs fluid flow, containment, and fluid-rock interaction, central to the safety and performance of geoenergy applications such as CO₂ and hydrogen storage, nuclear waste disposal, and geothermal energy production.

Recent advancements in laboratory experimental capabilities, field observation techniques, monitoring technologies, and numerical modelling methods have deepened our understanding of fault/fracture deformation, failure, and (re-)activation. These discontinuities act as conduits or barriers for fluid and heat flow, enhancing or impairing reservoir performance. Of particular concern are changes in thermo-hydro-mechanical-chemical (THMC) coupling associated with injection, fluid circulation, and extraction near faulted and fractured zones, which can alter transmissibility and structural stability.

Understanding these dynamics is crucial for predicting and mitigating risks associated with induced seismicity, leakage, and other subsurface hazards. These insights also improve the accuracy of numerical models used to predict fault behaviour at reservoir scales and guide the design and management of geoenergy projects.

We invite contributions from researchers exploring the role of faults and fractures in subsurface systems, particularly those involved in applied or interdisciplinary studies related to low-carbon technologies such as CO₂ and hydrogen storage, nuclear waste disposal, and geothermal energy production. We are particularly interested in research bridging the gap between laboratory-scale measurements and reservoir-scale processes, employing methods including but not limited to laboratory investigations, outcrop studies, in-situ experiments, monitoring, subsurface data analysis, and numerical modelling and simulation. Interdisciplinary approaches integrating geological, geophysical, and engineering perspectives are especially welcome.

The session aims to provide a comprehensive understanding of the impact of faults and fractures on subsurface energy systems, showcasing innovative methods for their characterisation, monitoring, and modelling.