Application of a Heuristic Method for the Estimation of S-Wave Velocity Structure. Earth Sci. Res. J. Vol 10, No 1 (Jun 2006): 41-51


Andrés José Alfaro Castillo

In this study seven arrays of microtremors in Tsukuba city were performed, located at North-Eastern edge of Kanto Basin, in order to estimate the deep S-wave velocity structure. The spatial autocorrelation method SPAC was used to determine phase velocity dispersion curves in the frequency range from 0.3-2.5 Hz. The determination of Vs profiles reached a depth of 750 m. Two methods were used to estimate the S-wave velocity structure: inversion method and a heuristic method means the combination of Downhill Simplex Algorithm with Very Fast Simulated Annealing Method. Comparisons with Vs from the existent results of