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Published on: April 10, 2017
Seismoelectric reflection and transmission at a fluid/porous-medium interface
Menne Schakel1, David Smeulders
1Department of Geotechnology, Delft University of Technology, 2600 GA Delft, The Netherlands. m.d.schakel@tudelft.nl
The Journal of the Acoustical Society of America
|January 12, 2010
Summary
Seismoelectric wave propagation in poroelastic media is modeled using effective densities. Key conversion coefficients are derived, showing electrolyte concentration, viscosity, and permeability significantly impact seismoelectric conversion.
Area of Science:
- Geophysics
- Poroelasticity
- Seismoelectrics
Background:
- Seismoelectric phenomena link seismic wave propagation and electromagnetic fields in porous media.
- Understanding these couplings is crucial for geophysical exploration and fluid detection.
Purpose of the Study:
- To formulate the dispersion relation for seismoelectric wave propagation in poroelastic media.
- To derive seismoelectric conversion coefficients for P-waves at a fluid-poroelastic interface.
- To analyze the influence of various parameters on seismoelectric conversion.
Main Methods:
- Formulation of dispersion relation using effective densities incorporating viscous and electrokinetic effects.
- Application of Helmholtz decomposition to derive seismoelectric conversion coefficients.
- Computation of dependency on angle of incidence and frequency.
- Verification of energy conservation using orthodox and interference fluxes.
Main Results:
- Two seismoelectric conversion coefficients were derived, quantifying P-wave to electromagnetic wave conversion.
- The study computed the dependency of these coefficients on incidence angle and frequency.
- Energy conservation was confirmed through flux analysis.
- Sensitivity analysis revealed significant influence of electrolyte concentration, viscosity, and permeability.
Conclusions:
- The derived coefficients accurately describe seismoelectric wave conversion at interfaces.
- Poroelastic properties like permeability and fluid properties like electrolyte concentration are critical for seismoelectric signal interpretation.
- The findings enhance the understanding of seismoelectric wave phenomena in geophysical applications.
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