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| Titel |
Frequency-dependent streaming potential of porous media: Experimental approaches and apparatus design |
| VerfasserIn |
Paul W. J. Glover, Jean Ruel, Eric Tardif |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250074176
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| Zusammenfassung |
| Electro-kinetic phenomena link fluid flow and electrical flow in porous and fractured media
such that a hydraulic flow will generate an electrical current and vice versa. Although such a
link is likely to be extremely useful, especially in the development of the electro-seismic
method, surprisingly few experimental measurements have been carried out, particularly as
a function of frequency because of their difficulty. We have carried out a study
that considers six different approaches to making laboratory determinations of the
frequency-dependent streaming potential coefficient of geomaterials. These are (i)
motor and scotch yoke, (ii) motor and cam, (iii) pneumatic drive, (iv) hydraulic
drive, (v) electro-magnetic drive, and (vi) piezo-electric drive. In each case, we
have analysed the mechanical, electrical, and other technical difficulties involved.
We conclude that the electro-magnetic drive is currently the only approach that
is practicable, while the piezo-electric drive may be useful for low permeability
samples and at specified high frequencies. We have used the electro-magnetic drive
approach to design, build, and test an apparatus for measuring the streaming potential
coefficient of unconsolidated and disaggregated samples such as sands, gravels,
and soils with a diameter of 25.4 mm and lengths between 50 mm and 300 mm. |
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