EGU23-6640, updated on 15 Jan 2024
https://doi.org/10.5194/egusphere-egu23-6640
EGU General Assembly 2023
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

A petrophysical model for the spectral induced polarization of clays

Philippe Leroy1, Alexis Maineult2, Aida Mendieta2, and Damien Jougnot2
Philippe Leroy et al.
  • 1BRGM, Water, Environment and Ecotechnologies, Orléans, France (p.leroy@brgm.fr)
  • 2Sorbonne Université, CNRS, EPHE, UMR 7619 METIS, Paris, France

Clays are sedimentary minerals that are ubiquitous in the Earth’s continental crust. They have remarkable adsorption, catalytic and containment properties due to their high surface charge and very large specific surface area. However, their microstructural and electrochemical properties are not completely understood. In this study, we have developed a new petrophysical model to interpret laboratory spectral induced polarization measurements on kaolinite, illite and montmorillonite muds when salinity increases (from around 0.01 mol L-1 to 1 mol L-1 NaCl initially). Our model considers electrical conduction in the bulk and diffuse layer waters as well as polarization of the Stern layers of illite aggregates and Stern layers and interlayer spaces of Na-montmorillonite aggregates with different shapes and sizes. Maxwell-Wagner polarization was considered as well. By fitting predicted to measured SIP spectra, we found that the basal surface of clays controls Stern layer polarization and that the interlayer space of Na-montmorillonite may polarize in the mHz to kHz frequency range. Our study is a step forward to better understand the high surface conductivity response of clays inferred from resistivity and induced polarization measurements.

How to cite: Leroy, P., Maineult, A., Mendieta, A., and Jougnot, D.: A petrophysical model for the spectral induced polarization of clays, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-6640, https://doi.org/10.5194/egusphere-egu23-6640, 2023.