Earthquake Early Warning (EEW) is an effective approach to mitigating earthquake 27 damages. This is the first study of evaluating the application of borehole seismographs 28 for EEW in Taiwan. We selected the inland and offshore earthquakes with ML larger 29 than 4.0 occurring between 2012 and 2014. We investigated the Pd attenuation 30 relationship as a function of hypocentral distance (R) and magnitude (M). The new Pd 31 attenuation relationship specific for the borehole records is expressed as: 32 log(Pd) = 0.689ML - 0.741 log(R) - 4.608 ± 0.248. 33 Once the earthquake location is determined, we could use this regression equation to 34 quickly estimate Pd magnitude (MPd). According to the new regression equation 35 specifically for the borehole observations in Taiwan, our result shows that the standard 36 deviation of MPd is about 0.21 relative to ML. This smaller standard deviation of 0.21 37 compared to that of the free-surface records might be attributed to the reduced influence 38 of the near-surface effect in the borehole records. We propose a new robust Pd regression 39 equation for the Taiwan borehole seismic network. 40.
All Science Journal Classification (ASJC) codes
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)