Our research has mainly focused on earthquake early warning and observational seismology in the Taiwan region.

    One of our major efforts has been the establishment of an earthquake early warning system in Taiwan to enable speedy response to damaging earthquakes. Following a large earthquake in Taiwan, utilizing a quick magnitude determination based on the first 10 sec of signals from a virtual and sub-network of seismic stations configured automatically, this system reduces the earthquake reporting time to 30 sec or less. This represents a significant step forward in earthquake early warning capability. This early warning system has been in operation at CWB since 2002 (Wu and Teng, BSSA, 2002; Wu et al., Springer Book chapter, 2007). Comprehensive earthquake reports have been issued mostly in less than 30 sec, with an average of about 22 sec from earthquake origin times. At 3 km/sec for a typical crustal shear-wave speed, the present performance is not useful if an earthquake occurs within 70 km from a city, but the lead time can be more than 10 sec for cities 100 km away from the earthquake source. In the latter case, a lead time of several seconds will allow pre-programmed emergency response to take place prior to the arrival of strong ground shaking.



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