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| Fractal heterogeneities in sonic logs
and low-frequency scattering attenuation | |
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Up: Scattering attenuation in 3D
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The energy spectrum,
, of von Kármán's autocorrelation
function in equation 7 is real and even:
Values of defined by equation 22 are
Coefficient , defined by equation 8, is an increasing function of exponent
and has to be calculated numerically, except for some specific values:
The dispersion relation of equation 21 solves for an explicit solution of attenuation and dispersion:
When , the derivation produces simple expressions as detailed in Appendix B.
The use of
with the Kramers-Krönig relation can be used
to determine the real part of .
In the context of the second-order approximation,
scattering attenuation in a von Kármán isotropic medium is
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(31) |
For , the scattering attenuation reduces to the Rayleigh diffusion regime:
Subsections
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| Fractal heterogeneities in sonic logs
and low-frequency scattering attenuation | |
|
Next: Penetration depth
Up: Scattering attenuation in 3D
Previous: Low-frequency waves in 3D
2013-07-26