Estimation of shear wave velocity profiles by the inversion of spatial autocorrelation coefficients

摘要: The subsurface shear-wave velocity (Vs) is considered to be a key parameter for site characterization and assessment of earthquake hazard because its great influence on local ground-motion amplification. Array microtremor measurements are widely used the estimation velocities. Compared other methods such as frequency-wavenumber (f-k) methods, spatial autocorrelation (SPAC) method requires fewer sensors thus relatively easier implement gives robust estimations profiles depths down few hundred meters. quantity derived from observed data SPAC coefficient, which function correlation distance, frequency phase velocity. Generally, Vs two stage process: Estimation dispersion coefficients inversion structure. In this study, instead inverting curves, more practical approach used; that is, directly inverted S-wave A synthetic case field application presented test potential algorithm. We obtain an iterative damped least-squares solution with differential smoothing. smoothing constrains change in velocities adjacent layers stabilizes inversion.