On 3-C geophone orientation and wave modes polarization

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CREWES 2003 Sponsors Meeting Weve presented our
research results and educational progress in
geophysical exploration in partnership with the
resource industry. Weve enjoyed visiting with
you! Thank you for your interest, comments, and
support.
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Continuing CREWES Focus in 2003-2004
SEISMIC LITHOLOGY FLUID IMAGING
INTERPRET. CASES
BOREHOLE HIGH-RES.
NUMERICAL MODELING
SIGNAL PROCESSING
PHYSICAL MODELING
FIELD OPS. INSTRUMENTS
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Future Research Risk and Reward
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Non-linear wave equation Non-welded contacts,
etc.
where u is local displacement
r0 is the density
b, d are amplitudes in nonlinear terms.
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Overtones generated by non-linear
propagation (Physics Today, 2001)
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Attenuation-relaxation imaging
Fluid-saturated rock
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• Seismoelectric phenomena (Gharibi, Bentley,
  Stewart)
• Elastic waves can induce electromagnetic fields
  through various coupling mechanisms.

rock matrix
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Linear relationship between EM and elastic
waveforms
Using a quasi-static approximation, ?(?)gtgt??(?),
(? electrical conductivity, ? dielectric
permittivity, ? angular frequency) and
plane-wave solution for an isotropic and
homogenous whole-space
E electric field H magnetic field U grain
displacement
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L(?,?,?,?,) is a function of fluids electric
conductivity (?), fluids dielectric constant
(?), shear viscosity (?), and bulk density
(?). T(?,?,?,?,G,) is a function of porosity
(?), fluids dielectric constant (?), shear
viscosity (?), bulk density (?), and shear
modulus (G).
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Estimation of physical properties
Compute L using
or
or
Compute T using
or
Invert L and T to estimate
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Seismoelectromagnetic survey
Layout of grounded dipole antennas, magnetic
sensors, and geophones about the shotpoints in
simultaneous recording of seismic and
seismoelectromagnetic surveys.
Single shot and receiver illustration of
simultaneous seismic and seismoelectromagnetic
survey.
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Thanks, see you soon!