William L. Ellsworth
Shunta Noda
2017
<p><span>We propose a method that utilizes the time dependence of </span><i>P</i><span>‐wave displacement amplitudes to estimate the final magnitude (</span><span class="inline-formula no-formula-id">M</span><span>) for earthquake early warning (EEW) before the arrival of the peak amplitude. A relation between </span><span class="inline-formula no-formula-id">M</span><span> and </span><i>P</i><span>‐wave displacement amplitude is employed for the method. Its value is set as a function of time from the </span><i>P</i><span> arrival, and is determined using a K‐NET dataset recorded in Japan from a scaling relation between </span><span class="inline-formula no-formula-id">M</span><span> and the time dependence of </span><i>P</i><span>‐wave displacement. A test to check the performance of the proposed equation demonstrates in a statistical sense that this technique enables us to estimate </span><span class="inline-formula no-formula-id">M</span><span> more rapidly than conventional methods without loss of accuracy. We conclude that the approach proposed in this article effectively gains a longer lead time as well as reduces the blind zone for EEW.</span></p>
application/pdf
10.1785/0120170048
en
Seismological Society of America
Determination of earthquake magnitude for early warning from the time-dependence of P-wave amplitudes
article