THE DECREASE OF UNCERTAINTY IN GROUND MOTION ESTIMATION BASED ON THE EMPIRICAL CORRECTION MODEL THE DECREASE OF UNCERTAINTY IN GROUND MOTION ESTIMATION BASED ON THE EMPIRICAL CORRECTION MODEL K. L. Wen 1,2,3), T. H. Wu 2), M. W. Huang 2), S. J. Jhang 2), C. L. Chang 2), S. Y. Liu 2), Y. W. Chang 3), C. M. Lin 3), and C. H. Kuo 3) 1)Institute of Geophysics, National Central University, Taiwan 2)National S&T Center for Disaster Reduction, Taiwan 3)National Center for Research on Earthquake Engineering, Taiwan The Next Generation of Research on Earthquake-induced Landslides: An International Conference in Commemoration of the 10th Anniversary of the Chi-Chi Earthquake Sep. 23, 2009, NCU, Taiwan

Model Setting Modeling Parameters Model diemnsion (km 3 ) 28(W) x 28(L) x 2.5(H) Absorb boundary (grids) ± 100 Source type Double-Couple Source location (km)(24,2,1) Source time function (sec) 0.16, 0.0, 0.16 Velocity (km/s 2 ) SunShang formation Vp=1.5, Vs=0.86 Basin Basement Vp=3.0, Vs=1.70 Outside the Basin Vp=4.5, Vs=2.60 3D Finite-Difference Modeling of Strong Ground Motion in the Taipei Basin

Basement + SunShang Formation by Lee et al.

Wen et al., 2009

Very Dense Strong Motion Network （ TSMIP ） ; Many Eq. Records

Attenuation Equation Geo-mean of two horizontal components. (Chien,2001)

Normalized Residual (NR i ) (Campbell, 1981) MR is the average value of Err i

Station Correction v.r.t. Attenuation Equation

Correction coefficient of each station SiteNameC0C1NdatSigma ALS ANP CHK CHN CHN CHN KAU KAU KAU WNT WSF WTP

Result from Att. Eq. 1999/9/21 Observed Result after Station Corr. Err.

Prob. of Charac. Eq. in next 50 yr. 50 年內 特徵地震發生機率 1. 米崙斷層 Milun F. 2. 新化斷層 Hsinhua F. 3. 大尖山 - 觸口斷層 Tachienshan-Chukou F % 50.60% 46.69% M L 7.3 M L 6.1 M L 7.3

Shake Map for (a) Milun Fault (M L =7.3), (b) Hsinhua Fault (M L =6.1), and (c) Tachienshan-Chukou Fault (M L =7.3) 新化斷層 Hsinhua F. 米崙斷層 Milun F. 大尖山 - 觸口斷層 Tachienshan-Chukou F.

1999/9/21 Chi-Chi Eq. Critical information available in 102 seconds ： Time ： 1:47 AM Magnitude ： M L 7.3 Epicenter ： Near Chi-Chi Regional intensity map. Shaking time histories.

EEW Ground Motion Estimation

RTD Stations as Reference Site 24 Zones Correlation

Correlation Sequence Table ChiaNan1 SiteNameRefRTSName ALS CHN5CHN4WTPWGK CHN4 CHN5ALSWGK CHN5 WTPALSWGKCHN4 CHY006CHN5WGKALSCHN4 CHY010ALSWGKCHN4 CHY011CHN5WGKALSCHN4 CHY014CHN5ALSCHN4WGK CHY024CHN4WGKALSCHN5 CHY028CHN5WGKALSCHN4 CHY034CHN4ALSCHN5WGK CHY042CHN4ALSCHN5WGK CHY045CHN4WGKCHN5 CHY074ALSCHN5CHN4WGK CHY080CHN5ALSCHN4WGK CHY083WGKCHN4CHN5ALS WGK CHN5ALSCHN4WTP CHN5ALSWGK

March 31, 2002 M L =6.8 Casualty: 5 death 272 injury

2002/03/31 Observed 2002/03/31 Result from 1st calculation 2002/03/31 Result from 2nd calculation 2002/03/31 Err i,iєS 2002/03/31 Result from 3rd calculation

PGAobs(g) Yatt(g) PGAsic(g) PGAsoc(g) σ= σ= σ= March 31, 2002 M L 6.8

PGV Estimation of the Sep. 25, 1999 M L 6.8 Earthquake 編 號編 號 發震時間 (UT) Longitude (°E) Latitude (°N) 日 期日 期時 間時 間 61999/09/2523:52: 規 模ML規 模ML 深 度 (km) 場址 修正前 σ 場址 修正後 σ 震源 修正後 σ (a) (b)(d) (c)(e) (f) (g)

~Thanks for Your Attention~ The Next Generation of Research on Earthquake-induced Landslides: An International Conference in Commemoration of the 10th Anniversary of the Chi-Chi Earthquake Sep. 23, 2009, NCU, Taiwan

A very dense microtremor survey had been done in the Taiwan area. Tokyo Sokushin: Recorder: SAMTAC-801B Sensor: VSE-311C. Total 3917 stations Station Interval ~ 2 km Sampling rate: 200 sps.