Rayleigh waves in the period range 0.2 - 3.0 s from eight quarry blasts are analyzed to obtain S-wave velocity model beneath the Příbram seven-station array in the Czech Republic. Locations and origin times of blasts are estimated using P- and S-wave onsets and then verified at the quarry in the vicinity of the location. This blind test confirms a sufficient precision of the location procedure for identification of quarries. Epicentral distances are in the range from 16 to 52 km. Group velocity dispersion curves of Rayleigh waves are determined by the frequency-time analysis. An average group velocity beneath the array for each period is computed with the help of mean travel-time curve for all blasts and stations. The resultant group velocity dispersion curve is inverted to obtain a 1-D S-wave velocity model using the Isometric method. The results are compared with known geological structure in the area of interest., Renata Gaždová, Petr Kolínský, Jiří Málek and Jan Vilhelm., and Obsahuje bibliografii
We apply a traditional method of surface wave tomography as a new approach to investigate the uppermost crust velocities in the Western Bohemia region (Czech Republic). It enables us to look for velocity distribution in a small scale of tens of kilometers. We measure Rayleigh wave group velocity dispersion curves in a period range 0.25 - 2.0 s along paths crossing the region of interest. We use modified multiple-filtering method for frequency-time analysis. We compute 2-D tomography maps of group velocity distribution in the region for eight selected periods using the standard methods and programs described in literature. We discuss the velocity distribution with respect to results of former study by Nehybka and Skácelová (1997). We present a set of local dispersion curves which may be further inverted to obtain a 3-D shear wave velocity image of the area., Petr Kolínský and Johana Brokešová., and Obsahuje bibliografické odkazy