Flow and transport are important in hydrology and many geo-engineering applications such as carbon dioxide storage, geothermal energy or in situ recovery. Developing a full understanding of the feedbacks between geochemical reactions and flow and transport at the reservoir scale requires investigations of geochemical mechanisms at the microscopic scale. Application of high-resolution and/or non-invasive imaging techniques like X-ray micro-tomography has considerably increased experimental capability by giving access to a spatio-temporal vision of the physical-chemical processes within the rocks [1]. New information is now accessible, which provides a better understanding of the coupled thermo-hydro-mechano chemical processes the pore scale [2,3] and allows numerical models to be better constrained. In my presentation, I will present some applications of 4D imaging related to reactive transport experiments and discuss the results and issues for reactive transport modelling. In particular, I would point out several processes that challenge the continuum description of porous media and assumptions required for reactive transport modelling at large scales [3].

[1] Noiriel C. and Renard F. (2022) 4D X-Ray Micro-Tomography Imaging of Dynamic Processes in Geosciences. Comptes-rendus Geoscience, vol. 354, 255-280, doi 10.5802/crgeos.137
[2] Noiriel C. and Daval D. (2017) Pore-Scale Geochemical Reactivity Associated with CO2 Storage: New Frontiers at the Fluid-Solid Interface. Accounts of Chemical Research, special Issue on Chemistry of Geologic Carbon Storage, DOI: 10.1021/acs.accounts.7b00019
[3] Noiriel C. (2015) Resolving time-dependent evolution of pore scale structure, permeability and reactivity using X-ray microtomography. Reviews in Mineralogy and Geochemistry, vol 80: Pore scale geochemical processes, p 247-286, C.I. Steefel S. Emmanuel and L. Anovitz Eds, DOI : 10.2138/rmg.2015.80.08
[4] Noiriel C. and Soulaine C. (2021) Pore-scale imaging and modelling of reactive flow in evolving porous media: tracking the dynamics of the fluid-rock interface. Transport in Porous Media, Special issue 35th Anniversary special issue in honour of Jacob Bear, vol. 140 (1), 201-213, doi 10.1007/s11242-021-01613-2dia

Catherine Noiriel is associate professor at University Paul Sabatier in Toulouse, France. Her research focuses on water-rock interactions, mineral reactivity, flow and reactive transport, from the experimental and numerical points of view to better understand the coupled thermo-hydro-mechanical-chemical processes (THMC) in reservoir rocks.