Strong Ground Motions Generated by the February 11, 2014 Tatunshan Earthquake in the Taipei Metropolitan Area

Abstract

Strong-motion seismograms from the 11 February, 2014 Tatunshan earthquake were recorded at stations around the source area. These recordings were used to analyze the strong-motion characteristics in the area. The largest peak ground acceleration (PGA) values of 100.7, 93.4, and 66.6 cm sec -2 in the vertical, EW, and NS directions, respectively, were recorded at station TAP056, about 4.9 km to the northwest of the epicenter. The PGA decays fast with distance, indicating high attenuation in the Tatun volcanic area. The PGA ratio of vertical to horizontal ground motions decreases with increasing epicenter distance. The PGA values in the EW component are larger than those in the NS component. This might be associated with the focal mechanism of the earthquake. The spectral accelerations decrease rapidly with increasing period.

Morlet Wavelet Analysis of ML ≥ 3 Earthquakes in the Taipei Metropolitan Area

“…Although seismicity in the TMA is relatively lower than other areas in Taiwan, numerous earthquakes have occurred in or near the TMA (Hsu 1961(Hsu , 1971Wang 1998;Wang et al 2006;Chen et al 2010Chen et al , 2014. During the Emperor Kanshi period of the Chin Dynasty, an event might have occurred in this area in April or May 1694, resulting in an earthquake-induced lake and the destruction of aboriginal houses (Hsu 1983a, b).…”