Fig. 14

Dispersion measurement for a single path by waveform fitting in a model space. a Modeled pair-specific 1-D shear velocity structure for the S-net station pair N.S2N08-N.S3N20. The thick and thin black lines represent the mean and standard deviation of the 1-D structures estimated by the bootstrap method. The gray line results from the reference model obtained by the array-based SPAC method in Fig. 13a. b Phase velocity dispersion curves of the fundamental-mode Rayleigh wave (0R), the first-overtone Rayleigh wave (1R), and the fundamental-mode Love wave (0 L). The thin blue and red lines are the means and three times standard deviations of the estimated pair-specific dispersion curves. The thick blue and red curves represent the frequency ranges that meet the quality control criteria based on variance reductions within narrow frequency bands. The gray ones are the results of the array-based measurement in Fig. 13b, c. c Fitting of the cross-spectra for this pair. The black and red are the data and the modeled cross-spectra, respectively. d Same as in (c), but both cross-spectra are normalized by the standard deviation of the cross-spectral data estimated from the array-based SPAC method. Taken from Takagi and Nishida (2022)