Geophysical quantification of water phases: influence of surface conductivity and temperature modelling

Abstract

SUMMARY The quantification of frozen and unfrozen water content in porous media is essential for understanding hydrological, thermal and mechanical processes in cold regions. Petrophysical joint inversion (PJI) frameworks that integrate seismic and electrical data offer promising tools for resolving water and ice distributions, yet these are often limited by simplified petrophysical models. Here, we extend a PJI framework that accounts for both electrolytic and surface conduction by incorporating temperature dependence through a soil freezing curve, which links liquid water content to temperature and cation exchange capacity within the inversion as a petrophysical constraint. Using synthetic data, we show that this formulation improves modelling of frequency-dependent resistivity and enhances estimates of water content and interfacial conductivity quantified by cation exchange capacity. Our results highlight the critical role of temperature in controlling subsurface electrical properties and demonstrate that neglecting these effects can lead to substantial errors in the ice and water estimates. The extended PJI framework provides a physically consistent basis for geophysical imaging of water phase dynamics in partially frozen systems, with broad applicability to cold-region hydrology and seasonally or perennially frozen environments.