Viktoriya Yarushina (Institute for Energy Technology, Norway)

Coupled Deformation, Flow, Reaction and Heat in Geological Systems: From First Principles to Predictive Models

Deformation and fluid flow are intrinsically coupled in geological systems and are further influenced by chemical reactions and heat transport. These interactions are important across a wide range of problems, from geodynamic processes to subsurface engineering applications. Yet models that consistently account for all four components remain challenging to formulate and implement. The difficulties arise from the multiscale nature of the underlying processes, the complexity of the coupled physics, and the numerical stiffness and instabilities that often accompany strongly coupled formulations. This talk discusses approaches for building coupled thermo-hydro-mechano-chemical models that are physically transparent, thermodynamically consistent, and suitable for numerical implementation. Starting from macroscale conservation laws formulated in an Eulerian framework, we derive governing equations and constitutive constraints for porous materials undergoing elastic, viscous, plastic, thermal, and reaction-driven evolution. Particular attention is given to formulations that recover established classical models in the appropriate limiting cases, providing important checks on both their physical and mathematical consistency. Constitutive closure is then constrained by microscale processes, including pore geometry, mineral reactions, grain-scale deformation, and evolving interfaces, all of which influence effective rheology and transport properties.