Micro-tremors at 37 sites were observed and measured. Correlations among the micro-tremor H/V spectra predominant frequency and site characteristic parameters including thickness of sediment, equivalent shear wave velocities in different depths, and site period were studied. Comparing these correlations and the study results of ground motion H/V spectra in different regions, the feasibility and accuracy of using the micro-tremor H/V spectra method to quickly measure site characteristic parameters were explored. Results showed that the predominant frequency of micro-tremor H/V has a strong correlation with the thickness of sediment, if using the micro-tremor H/V spectra method to measure thicknesses of sediment in different regions, their relative differences within a frequency range of 1~2Hz are less than 15%, the relative differences increase beyond this frequency range; the predominant period of the micro-tremor H/V spectra is almost the same as the site sediment equivalent period; when the micro-tremor H/V spectra’s predominant period >0.5s, the site’s equivalent shear wave velocities Vs20 and Vs30 as well as equivalent periods Ts20 and Ts30 have little changes, they have average values of 200m/s，250m/s，0.8s and 0.6s, respectively.
Key words
micro-tremor /
H/V spectra /
thickness of sediment /
site period /
equivalent shear wave velocity
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