GeoElectricMixing · Geophysical Signature of Subsurface Reactive Mixing
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2017-04-01 → 2019-03-31
- EU contribution
- €173,076
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Geophysical Signature of Subsurface Reactive Mixing
Subsurface reactive processes play a key role in dictating the evolution of subsurface environments, their interaction with surface water bodies and the migration and remediation of transported contaminants. In particular, reactive hot spots tend to concentrate in mixing fronts between fluids of different compositions, such as recently infiltrated/injected fluids and resident groundwater, which develop in a range of situations, including CO2 sequestration operations and geothermal systems, and contaminant remediation operations. Our understanding of the development and temporal dynamics of these hotspots is currently hampered by the limited spatial resolution of the sampling offered by boreholes. Recent breakthroughs in geoelectrics may however profoundly change our vision of these phenomena by providing non-invasive techniques with a large spatial resolution and high sensitivity to many geological processes. The overall objective of the project “GeoElectricMixing” is to quantitatively link reactive mixing dynamics to geo-electrics signals (complex impedance and electrical self-potential) to open a new window on the in situ characterization of subsurface mixing hotspots and associated reaction rates. The key idea behind the project is to consider special reactions which can potentially generate chemical species with a stronger sensitivity to externally applied electric fields than that of the reactants, so that the electrical measurements can provide accurate detection of mixing hotspots in the subsurface. This overall objective was divided into two specific objectives. The SO1 is mainly associated with (i) developing theoretical models to couple electrokinetics (or, electrohydrodynamics) to flow-induced reactions in a porous medium, and (ii) subsequent upscaling of the coupled transport processes to Darcy and Field scales. The SO2 was devoted to experimental investigations of the electrical signatures of reactive mixing at laboratory scale.
Data: CORDIS, © European Union
Project objective
Subsurface reactive processes play a key role in dictating the evolution of subsurface environments, their interaction with surface water bodies and the migration and remediation of transported contaminants. In particular reactive hot spots tend to concentrate in mixing fronts between fluids of different compositions, such as recently infiltrated/injected fluids and resident groundwater, which develop in a range of situations, including CO2 sequestration operations and geothermal systems, contaminant remediation operations, and reactive hyporheic zones beneath rivers. Our understanding of the development and temporal dynamics of these hotspots is currently hampered by the limited sampling offered by boreholes. Recent breakthroughs in geoelectrics may however profoundly change our vision of these phenomena by providing non-invasive techniques with high sensitivity to many geological processes. GeoElectricMixing will hence develop a novel approach to investigate the temporal dynamics of reactive mixing processes from Complex Impedance and Self Potential signals. The coupling of reactive mixing and geoelectrics will be quantified and upscaled by integrating charge transport and polarization phenomena in a new modeling framework, recently developed by the host to predict the spatial distribution of chemical species and reaction rates across mixing fronts (WP1). Dedicated experiments will then be designed by integrating electrodes in a novel millifluidic setup to monitor jointly the temporal evolution of geoelectrical parameters and the spatial distribution of concentrations and reactions rate in a reactive mixing front progressing through the cell (WP2). GeoElectricMixing is thus expected to open a new window on subsurface reactive mixing phenomena, expanding our capacities to detect and quantify these processes in situ, and thus providing critical data to unlock current open questions on the dynamics of mixing processes and their role in reaction enhancement.
Original text from CORDIS.
Participants
- UNIVERSITE DE RENNES · RennesCoordinatorFrance
Links
Data: CORDIS, © European Union