Determining the Success of Strong Motion Records in Calculating P-Wave Moment Magnitude

Abstract

Earthquake early warning systems have high importance and improving continuously using different analysing techniques. The system depends on calculating a magnitude in a short time with as high accuracy as possible. Large earthquakes that have tsunami potential occurred and will be occurred especially in the Mediterranean and Aegean Seas Turkey has settlements along these coastlines. In practice, weak-motion (velocity) records are generally used to determine the magnitude, but these seismic records have a disadvantage: a clipping problem around the epicentre. Up to now, there is not much work on the study of the strong-motion (acceleration) records to calculate the magnitude of an earthquake in a short time with high accuracy. This study focused on calculating the P-wave moment magnitude using P-wave body waves recorded at strong motion seismic stations caused by possible tsunami source region earthquakes. For that reason, we used three earthquakes that have a magnitude larger than 6.0 Mw. The difference between the Global Centroid Moment Tensor (GCMT) moment magnitude is about 0.2 m.u. which is acceptable considering an early warning purpose.