Filters








1 Hit in 0.038 sec

On estimation of earthquake magnitude in Earthquake EarlyWarning systems

Vladimir Sokolov, Friedemann Wenzel, Takashi Furumura
2009 Earth, Planets and Space  
Determination of earthquake magnitude from the initial P-wave portion of ground motion is the key problems for Earthquake Early Warning (EEW). We analyzed performance of scaling relations between one of the frequently used early warning parameters, so-called characteristic period τ C and moment magnitude M W in respect of (a) characteristics of datasets accumulated in various regions (earthquake depth, characteristics of network) and (b) variation of initial conditions applying for
more » ... ng for determination of the parameter τ C (length of Pwave window, number of used stations). The used data contain strong-motion records from 110 earthquakes (moment magnitude range 4.4-7.6) occurred in Japan and Taiwan. We show that, although the standard error of regression τ C = f (M W ) in general becomes smaller with the increase of the length of P-wave window (PL) and the number (N ) of averaged observations (stations), the uncertainty in estimation of M W given observed τ C does not decrease further for PL > 3-4 seconds and N > 3-4 stations. The information about earthquake depth also plays an important role in reducing the uncertainty of magnitude estimations. The table of confidence limits for estimations of the moment magnitudeM W based on observations of the characteristic period τ C is provided.
doi:10.1186/bf03352981 fatcat:m5wv7gyfuffpnneufgudbavkui