Using Stochastic Finite-Fault Method with Site Correction to Simulate Ground Motion from 2010 Jiashian,Taiwan,Earthquake

 

Speaker:Fu-Ming Wu

Date: 2013/04/18

Abstract

The stochastic finite fault method is applied to simulate records of 2010 Jiashian, Taiwan, earthquake. This study used the method which can divide the fault plane of large event into subfaults, and each subfault is treated as each point source and assigned an ω2 spectrum. The method consists of two steps. First, class B stations (NEHRP) of free field in southern Taiwan are used to calibrate model and found an excellent model with smaller average model bias. Model bias defined as the logarithm of the ratio of the FAS (Fourier amplitude spectrum) of observation to that of simulation. Second, use calibrated model to multiply transfer function to derive synthetic acceleration waveform of soil site.The transfer function in this study is H/V ratio (Nakamura, 1989; Lerom and Chavez-Garcia, 1993) of seismic event that derived by 1991 to 2009 from CWB (Central Weather Bureau) database. Then, we use the spectrum result from the calibrated model and multiply by the transfer function to get the simulated waveform of horizontal component. The result also compare with the observed record and attenuation relationship.

 

Reference

• Lee, S. J., Mozziconacci, L., Liang, W.-T., Hsu, Y.-J., Huang, W.-G., and Huang, B.-S. (2012). “Source complexity of the 4 March 2010 Jiashian, Taiwan, Earthquake determined by joint inversion of teleseismic and near field data,” Journal of AsianEarth Sciences., Doi: http://dx.doi.org/10.1016/j.jseaes.2012.11.018 .

• Motazedian, D., and Atkinson, G., (2005). “Stochastic ?nite-fault model based on dynamic corner frequency,” Bulletin of the Seismological Society of America., 95(3), 995–1010.

  Nakamura, Y., (1989), “A method for dynamic characteristies estimation of subsurface using microtremor on the ground surface,” QR of RTRI, 30(1), 25-33.