Electrokinetic coupling in unsaturated porous media
type: Dataset
description: The aim of this PhD thesis is to study electrokinetics for unsaturated conditions, both through streaming potential (SP) and seismo-electrics conversion. Electrokinetic coupling results from the motion of charges inside the water. Using an experimental approach, (SP) have been measured during drainage experiments in sand. These measurements were combined with hydrodynamics measurements and led to the first continuous recordings of streaming potential coefficient C as a function of water saturation Sw. The normalized streaming potential coefficient was found to be not monotoneously dependent on water saturation. Values of C increases first when Swdecreases until a maximum value for Sw around 65-85 %, and then decreases for decreasing saturation. In addition, experimental electrokinetic coefficient seems to be larger up to two orders of magnitude than classical values measured for saturated conditions. A similar behaviour was observed for three drainage experiments. The second part of this manuscript deals with the modelling of this unexpected behaviour. A new model, including a dynamic component linked to pressure temporal variations, is proposed. Modelling results show that this component is necessary to explain electrokinetic coefficient data of the first experiment, particularly for Sw =[0. 65-0. 85 ; 1]. Processing of the last experiment suggests that hydrodynamic conditions, and particularly the instant fluid flow magnitude, could be involved in the behaviour of C. The third part of this work deals with a field approach using seismoelectrics. Seismoelectric amplitudes have been studied for unsaturated conditions computing transfert functions defined as Ex/üx. First, the soil water saturation map has been deduced from the joint processing of GPR and ERT data. Thus, seismoelectric amplitudes deduced from P wave and surface waves independently, have been compared to water-content and measured electrical resitance. Results suggest that these amplitudes are smaller i…
landing page: https://theses.hal.science/tel-00872163
keyword: ecoulements-non-satures
keyword: electrofiltration
keyword: electrokinetics
keyword: hydrogeophysics
keyword: hydrogeophysique
keyword: infoeu-reposemanticsdoctoralthesis
keyword: physphysphys-geo-phphysics-physicsphysics-physicsgeophysics-physicsgeo-ph
keyword: potentiels-spontanes
keyword: sdustugpsciences-of-the-universe-physicsearth-sciencesgeophysics-physicsgeo-ph
keyword: sdustusciences-of-the-universe-physicsearth-sciences
keyword: self-potential
keyword: sismoelectrics
keyword: sismoelectrique
keyword: sismomagnetics
keyword: sismomagnetique
keyword: streaming-potential
keyword: teneur-en-eau
keyword: theses
keyword: unsaturated-flows
keyword: vadose-zone
keyword: water-content
keyword: zone-non-saturee
issued: 2026-05-09T09:52:20.458235
modified: 2026-05-09T09:52:20.458239
language: fr
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

Electrokinetic coupling in unsaturated porous media
type: Distribution
format: HTML
access URL: https://theses.hal.science/tel-00872163
issued: 2026-05-09T09:52:20.488199
modified: 2026-05-09T09:52:20.429907