HR: 1340h
AN: S23B-0307 [Abstracts]
TI: Scattering Wave Energy in a Random Isotropic Scattering Medium
AU: * Zeng, Y
EM: zeng@seismo.unr.edu
AF: Institute of Earth Sciences, Academia Sinica,, Taipei, 115-29
Taiwan
AU: * Zeng, Y
EM: zeng@seismo.unr.edu
AF: Seismological Lab, University of Nevada, Reno, NV 89557
United States
AB:
Among many of Aki's theoretical contributions to seismology is his work on the origin of the coda waves (Aki, 1969).
Following his work, many new theories have been proposed to explain the seismic scattering waves. For example, Zeng et al.
(1991) has extended the single isotropic scattering theory (Aki and Cheout, 1975; Sato, 1977) to multiple isotropic
scattering theory. Zeng (1993) and Sato (1994) have proposed a multiple scattering theory that includes P and S waves
scattering conversion and examined the evolving energy budget between P and S waves. Later, Sato (1995) extended the theory
to consider non-isotropic scattering. In this paper, I will show example of applying the scattering theory to near-field
strong ground motion simulation. The result shows that the scattering waves dominate the wave field at later arriving time
and of near nodal radiation components. I also extend the scattering theory to include scattered surface waves and surface
and body waves scattering conversions. The results show that scattered body wave energy can be well approximated by body to
body wave scattering at short distances. At large distances, scattered surface waves will dominate body waves for the near
surface stations.
DE: 7255 Surface waves and free oscillations
DE: 7260 Theory and modeling
DE: 7203 Body wave propagation
SC: Seismology [S]
MN: 2004 AGU Fall Meeting