HR: 0800h
AN: T11D-1306    [Abstracts]
TI: Coseismic displacement distribution of the strong motion records during the 10 December 2003 Chengkung, Taiwan earthquake
AU: * Wu, Y
EM: drymwu@ntu.edu.tw
AF: Department of Geosciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Chen, Y
AF: Department of Geosciences, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Kuochen, H
AF: Central Weather Bureau, No. 64, Kung-Yuan Road, Taipei, 100 Taiwan
AU: Chang, C
AF: Central Weather Bureau, No. 64, Kung-Yuan Road, Taipei, 100 Taiwan
AU: Wu, C
AF: Central Weather Bureau, No. 64, Kung-Yuan Road, Taipei, 100 Taiwan
AB: The Chengkung earthquake (Mw=6.8) took place on December 10, 2003 was located to 23.106N and121.324E along the eastern coast of Taiwan near the town of Chengkung with the focal depth of 15.7 km. The mainshock was felt throughout Taiwan Island. This earthquake triggered many strong motion stations of the Taiwan Strong Motion Instrumentation Program (TSMIP) that deployed by the Central Weather Bureau (CWB). For a large earthquake occurs at near source region, the ground motion can be on scale recording by strong motion instrument. Permanent displacement signal can be determined after twice integrations with necessary baseline correction. In this study, we calculated 120 coseismic displacements from forty TSMIP strong motion records to study the source dislocation model. Displacement results show, for the northern part (Chengkung) of the study region, magnitudes of horizontal displacements moved toward the north-east direction increase from 3-4 cm in the longitudinal valley (LV) to 7-10 cm in the coastal line. The most horizontal displacements in the southern part (Taitung) of the study area were measured 2-3 cm in the south-west directions. In the epicenter region the maximum uplift was about 18 cm. For understanding the coseismic displacements caused by the 2003 Chengkung earthquake, Okada (1992) method is used to inverse fault plane dislocation. Results show major fault was located from Taitung to Chengkung. Fault length is 40 km and width is 20 km initial at depth 10 km. Fault plane solution are strike 22, dip 50 and slip 64. The averaged slip is 60 cm and Mw is 6.7. This result is reasonable agree with the result of moment tensor inversion solution of Mw=6.8 from Harvard Centroid Moment Tensor solution (strike, 10; dip, 50; slip, 69).
DE: 1709 Geodesy
DE: 1734 Seismology
DE: 1744 Tectonophysics
DE: 1794 Instruments and techniques
SC: Tectonophysics [T]
MN: 2004 AGU Fall Meeting