Rapid Assessment of Damage Potential of Earthquakes in Taiwan from the Beginning of P Waves

To rapidly assess the potential for damage of an earthquake for purposes of earthquake early warning in Taiwan, we used the peak displacement and velocity amplitudes of the first 3 sec of the P wave. The vertical-component records, high-pass filtered at 0.075 Hz, are used. We found that the peak initial-displacement amplitude (Pd) correlates well with the peak ground-motion displacement (PGD) and the peak ground-motion velocity (PGV) at the same site. When Pd > 0.5 cm, the event is most likely damaging. If Pd is combined with the period parameter τ_c, determined in an earlier study, then τ_c × Pd provides an even more robust parameter for assessing the potential for damage.