A series of laboratory experiments, including measurements of electrical properties, permeability, and porosity, were performed on saturated sand-clay mixtures. Different mixtures and packing geometries of quartz sand and 0 to 10% Na-montmorillonite clay were investigated using solutions of CaCl2 and deionized water. Two main regions of electrical conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. For low fluid conductivities, the sample geometry was found to greatly affect the magnitude of the surface conductance. The influence of the microstructural properties on the electrical properties was quantified by estimating formation factors, Λ-parameters, and surface conductances. The surface conductances estimated using the theory of Johnson et al. 1986 agreed well with measured values. We suggest that high and low bounds on the expected surface and bulk conductances in a natural system can be derived from the measurements on these artificial geometries.
Description
On the relationship between microstructure and electrical and hydraulic properties of sand‐clay mixtures
%0 Journal Article
%1 dortherelationship
%A Wildenschild, Dorthe
%A Roberts, Jeffery J.
%A Carlberg, Eric D.
%D 2000
%I American Geophysical Union
%J Geophys. Res. Lett.
%K 200 electrical-conductivity hydraulic microstructure properties relationsship sand-clay
%P --
%T On the Relationship between Microstructure and Electrical and Hydraulic Properties of Sand-Clay Mixtures
%U http://dx.doi.org/10.1029/2000GL011553
%V 27
%X A series of laboratory experiments, including measurements of electrical properties, permeability, and porosity, were performed on saturated sand-clay mixtures. Different mixtures and packing geometries of quartz sand and 0 to 10% Na-montmorillonite clay were investigated using solutions of CaCl2 and deionized water. Two main regions of electrical conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. For low fluid conductivities, the sample geometry was found to greatly affect the magnitude of the surface conductance. The influence of the microstructural properties on the electrical properties was quantified by estimating formation factors, Λ-parameters, and surface conductances. The surface conductances estimated using the theory of Johnson et al. 1986 agreed well with measured values. We suggest that high and low bounds on the expected surface and bulk conductances in a natural system can be derived from the measurements on these artificial geometries.
@article{dortherelationship,
abstract = {A series of laboratory experiments, including measurements of electrical properties, permeability, and porosity, were performed on saturated sand-clay mixtures. Different mixtures and packing geometries of quartz sand and 0 to 10% Na-montmorillonite clay were investigated using solutions of CaCl2 and deionized water. Two main regions of electrical conduction exist: a region dominated by surface conduction and a region where the ionic strength of the saturating fluid controlled conduction. For low fluid conductivities, the sample geometry was found to greatly affect the magnitude of the surface conductance. The influence of the microstructural properties on the electrical properties was quantified by estimating formation factors, Λ-parameters, and surface conductances. The surface conductances estimated using the theory of Johnson et al. [1986] agreed well with measured values. We suggest that high and low bounds on the expected surface and bulk conductances in a natural system can be derived from the measurements on these artificial geometries.},
added-at = {2009-10-02T10:50:22.000+0200},
author = {Wildenschild, Dorthe and Roberts, Jeffery J. and Carlberg, Eric D.},
biburl = {https://www.bibsonomy.org/bibtex/2ecab6aa9545c41558e07ec02635f8611/aglinda},
description = {On the relationship between microstructure and electrical and hydraulic properties of sand‐clay mixtures},
interhash = {72c78a6c1451851c3ffb6469d5421f93},
intrahash = {ecab6aa9545c41558e07ec02635f8611},
journal = {Geophys. Res. Lett.},
keywords = {200 electrical-conductivity hydraulic microstructure properties relationsship sand-clay},
pages = {--},
publisher = {American Geophysical Union},
timestamp = {2009-10-02T10:50:22.000+0200},
title = {On the Relationship between Microstructure and Electrical and Hydraulic Properties of Sand-Clay Mixtures},
url = {http://dx.doi.org/10.1029/2000GL011553},
volume = 27,
year = 2000
}