摘要This study investigates seismic interferometry in which the Green’s function is estimated between two receivers by cross-correlation and integration over sources. For smoothly varying source strengths, the dominant contributions of the correlation integral come from the stationary phase directions in the forward and backward directions from the alignment of the two receivers. Gaussian beams can be used to evaluate the correlation integral and concentrate the amplitudes in a vicinity of the stationary phase regions instead of completely relying on phase interference. Several numerical examples are shown to illustrate how this process works. The use of Gaussian beams for the evaluation of the correlation integral results in stable estimates, and also provides physical insight into the estimation of the Green’s function based on seismic interferometry.
Abstract：This study investigates seismic interferometry in which the Green’s function is estimated between two receivers by cross-correlation and integration over sources. For smoothly varying source strengths, the dominant contributions of the correlation integral come from the stationary phase directions in the forward and backward directions from the alignment of the two receivers. Gaussian beams can be used to evaluate the correlation integral and concentrate the amplitudes in a vicinity of the stationary phase regions instead of completely relying on phase interference. Several numerical examples are shown to illustrate how this process works. The use of Gaussian beams for the evaluation of the correlation integral results in stable estimates, and also provides physical insight into the estimation of the Green’s function based on seismic interferometry.
基金资助:U.S. National Science Foundation EAR06-35611 and U.S. Air Force contract FA8718-08-C-002 and partly by the members of the Geo-Mathematical Imaging Group (GMIG) at Purdue University
通讯作者:
Robert L. Nowack
E-mail: nowack@purdue.edu
引用本文:
Robert L. Nowack. Seismic interferometry and estimation of the Green’s function using Gaussian beams[J]. 《地震学报》英文版, 2010, 23(5): 417-424.
Robert L. Nowack. Seismic interferometry and estimation of the Green’s function using Gaussian beams. Earthquake Science, 2010, 23(5): 417-424.
