Near-Source Strong Ground Motion Characteristics of the 2018 MW 6.4 Hualien Earthquake in Taiwan

Zengping Wen

Submitted August 11, 2019, SCEC Contribution #9419, 2019 SCEC Annual Meeting Poster #008

The free-field strong ground motions recorded at 30 sites in near fault regions in the 6 February 2018 Mw 6.4 Hualien Earthquake in Taiwan were used to examine the near-source strong ground motion characteristics. The magnitude of vertical and horizontal peak ground accelerations (PGAs), frequency content of acceleration histories are analyzed. The rupture directivity mainly affects PGV and spectral acceleration for periods of larger than 1 s, whereas it does not affects PGA and spectral acceleration for periods of shorter than 1 s. The pulse-like ground motions are mainly concentrated along the Milun fault and are characterized by a long pulse period and a highly amplification. Spectral acceleration for periods of larger than 1 s, the residual ground motions (i.e., removed the pulse from the observed ground motion) are show good coincidence with the NGA-West2 models in both horizontal and vertical direction, Whereas spectral acceleration for periods of shorter than 1 s, the residual ground motions were significantly lower than the NGA-West2 models.

Key Words
strong motion, pulse, near source

Citation
Wen, Z. (2019, 08). Near-Source Strong Ground Motion Characteristics of the 2018 MW 6.4 Hualien Earthquake in Taiwan. Poster Presentation at 2019 SCEC Annual Meeting.


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