ISSN:
1420-9136
Keywords:
Wave scattering
;
attenuation
;
random media
;
reflectivity method
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract The concept of attenuation operators and complex velocities is applied to scattering attenuation in two and three dimensions, using the minimum-phase assumption for the attenuation operator. Acoustic 2D finite-difference computations of synthetic seismograms show, that the attenuation operator describes well the decay and lowpass filtering of the averaged wave form, which follows from averaging travel-time-corrected wave forms along the wave front. In the case of exponential random media, analytical forms of the attenuation operators and complex velocities are available. The complex velocities are incorporated into the reflectivity method. As an application, synthetic seismograms are presented for theS n wave, attenuated by lithospheric velocity and density fluctuations. The limitations of attenuation operators and complex velocities for scattering are also discussed. With these quantities it is not possible to model phenomena related to the scattered waves themselves, such as amplitude and travel-time fluctuations along the wave front, codas and precursors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00882063
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