Open AccessGaussian beam methods and theoretical seismograms
Author(s) -
Katchalov A. P.,
Popov M. M.
Publication year - 1988
Publication title -
geophysical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0952-4592
DOI - 10.1111/j.1365-246x.1988.tb03874.x
Subject(s) - seismogram , caustic (mathematics) , gaussian , computation , fourier transform , gaussian beam , beam (structure) , spectral density , mathematics , mathematical analysis , optics , computational physics , physics , geology , algorithm , statistics , quantum mechanics , seismology
SUMMARY Two Gaussian beam methods for the computations of theoretical seismograms are suggested and tested on model problems. The first is based on using of space–time Gaussian beams instead of stationary ones. The second consists in replacing the Fourier‐frequency integral by a sum of residues at the poles of spectral density of a time pulse (some additional analytic restrictions on the spectral density are required). The main advantages of the methods are as follows (1) they enable us to avoid the computations of Fourier‐frequency transform; (2) they overcome caustic problems as does the Gaussian beam method in stationary problems. Numerical experiments confirm the efficiency of the methods for the computations of non‐stationary elastic wavefields.