HR: 0800h
AN: S51A-0234    [Abstracts]
TI: Estimation of Seismic Hazard Potential in Taiwan Based on Earthquakes with Mw >5 in 1900-2006
AU: * Liu, K
EM: lk.sung99@msa.hinet.net
AF: General Education Center & Hazard Mitigation Research Center, Kao Yuan University, 1821 Chung-Shan Rd, Lu-Chu Hsiang, Kaohsiung County, Tai 821, Taiwan
AU: Tsai, Y
EM: yibentsai@gmail.com
AF: Pacific Gas and Electric Company, 481 Patrick Way, LOs Altos, San Francisco, Cal 94022, United States
AB: Taiwan is located in the circum-Pacific seismic belt with high seismicity. In last century many damaging earthquakes have taken place in Taiwan. Reliable assessment of seismic hazards is fundamental for effective earthquake disaster mitigation. Reliable seismic hazard assessment in turn requires accurate ground motion estimates. A catalog of more than 1840 shallow earthquakes with homogenized Mw magnitude ranging from 5.0 to 8.2 in 1900-2006 (Chen and Tsai, 2008) is used to estimate the seismic hazard potential in Taiwan in the form of ShakeMap (Ward et al., 1999). First, we use the empirical attenuation relationships obtained for Taiwan by Liu and Tsai (2005) to calculate the peak ground acceleration (PGA) and peak ground velocity (PGV) for earthquakes in above-mentioned catalog at each grid point, with exception of the Mw 7.7 Chi-Chi earthquake for which actual observations are used. Secondly, the site response factor is incorporated in the present PGA and PGV prediction models at all grid points. Such prediction models will result in more realistic peak ground motion estimates for assessment of seismic hazard potential. Finally, we combine above results with the observed PGA and PGV contour maps of Chi-Chi earthquake. As a result, the ShakeMap patterns show that rupturing of the Chelungpu fault definitively affected the spatial distribution of ground motions. High MMI intensity greater than IX located in the hanging wall of the northern part of the Chelungpu fault, is related to high PGV (about 300 cm/sec) recorded at TCU068 (Shihkang station). In addition, high MMI intensity greater than VIII in Nanao area in northeastern Taiwan, Taichung and Chianan areas in western Taiwan, Hualien and Taitung areas in eastern Taiwan are all related to large damaging earthquakes occurred in these areas. Nevertheless, it should be noted that relatively low seismic hazard potential in Changhua area with MMI intensity lower than VI may be misleading, considering occurrence of damaging historical earthquakes before 1900 and presence of Changhua fault in the area.
DE: 7200 SEISMOLOGY
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 7294 Seismic instruments and networks (0935, 3025)
SC: Seismology [S]
MN: 2007 Fall Meeting