HR: 0800h
AN: S31A-0285    [Abstracts]
TI: Extracting the Green's function out of ambient noise and one explicit explanation based on a wave field division method
AU: * Liang, C
EM: cliang@memphis.edu
AF: Center for Earthquake research and Information, University of Memphis, 3876 Central Ave., Memphis, TN 38152
AU: Langston, C A
EM: clangstn@memphis.edu
AF: Center for Earthquake research and Information, University of Memphis, 3876 Central Ave., Memphis, TN 38152
AB: We cross-correlate 10 hours of ambient noise data recorded by station pairs and stack to extract the Green's function between two stations. Based on particle motion analysis, the dominant signals on correlated seismograms are Rayleigh waves on vertical and radial components and Love waves on transverse components. SH waves are also clear enough to be identified on most of transverse components, however, SV and P waves are comparatively weak. Rotating seismograms to proper directions certainly helps to amplify the strength of SV waves of many station pairs. The extraction of the Green's function between two stations by cross-correlation can be explicitly demonstrated by a wave field division method based on acoustic wave propagation. This method reveals that the cross-correlation process is equivalent to solving the "horizontal" receiver function problem in the sense of deconvolving source time functions from response functions, except that the source time functions are random in this special case. Numerical experiments and mathematical derivations are presented to support this schema.
DE: 7200 SEISMOLOGY
DE: 7218 Lithosphere (1236)
DE: 7255 Surface waves and free oscillations
DE: 7290 Computational seismology
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: Fall Meeting 2005