Re-examination of the Epicenter of the 16 September 1994 Taiwan Strait Earthquake Using the Beam-forming Method

The source location of the 16 September 1994 Taiwan Strait earth quake was relocated based on the beam-forming method using joint seis mic observations from regional seismic networks in Taiwan and Fujian and the International Seismological Center Bulletin. The revised epicenter is located at latitude 22.37 N (0.03) and longitude 118.63 E (0.03). Re sults of this study showed that the location uncertainty has been signifi cantly reduced using this approach. Decomposition tests of this study showed that the epicenters of Taiwan Strait events can be determined by the beam forming method using data from densely distributed seismic stations in Tai wan. However, source depths of Taiwan Strait events can not be deter mined unambiguously using the first P-arrivals only. Seismic waveform data should be carefully re-examined using this method to investigate earth quake source properties and seismicity of the Taiwan Strait region.