HR: 1340h
AN: T13E-1638    [Abstracts]
TI: Estimations of the S-Wave Velocity Structures at the Puli Area, Taiwan, Using the Array Records of Microtremors
AU: * Huang, H
EM: seihuey@eq.ccu.edu.tw
AF: Institute of Seismology, National Chung Cheng University, 168, University Rd., Min-Hsiung, Chia-Yi, 621, Taiwan
AU: Wu, C
EM: sei9010@eq.ccu.edu.tw
AF: Institute of Seismology, National Chung Cheng University, 168, University Rd., Min-Hsiung, Chia-Yi, 621, Taiwan
AB: In Puli, the collapse of many structures during the Chi-Chi earthquake was very closely related to the site effects (Huang and Tarng, 2005). The Shallow Shear-wave velocities have widely been used for earthquake ground- motion site characterization. Thus, the S-wave velocity structures of the Puli area are investigated using the array records of microtremors at three sites (CUH, NAK and PUL). The dispersion curves at these sites are calculated using the F-K method (Capon, 1969); then, the S-wave velocity structures at the Puli area are estimated by employing the surface wave inversion technique (Herrmann, 1991). Compared with CUH and NAK, PUL has higher phase velocities at frequencies of 2-6 Hz and lower values at frequencies of 0.3-1.3Hz. If the S-wave velocity of bedrock is assumed to be 2000m/sec, the depths of the alluvium at the Puli area are between 450m (NAK) and 660m (PUL). Besides, three distinct interfaces (330-420m, 570-630m, and 800-840m) exist in the shallow velocity structure. The above results are in good agreement with those using the seismic exploration method (Wang et al., 2002).
DE: 7200 SEISMOLOGY
DE: 7212 Earthquake ground motions and engineering seismology
SC: Tectonophysics [T]
MN: 2007 Fall Meeting