ausblenden:
Schlagwörter:
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Zusammenfassung:
Magnitude is a fundamental source parameter facilitating the characterisation of the size and amount of energy released by earthquakes and other types of seismic events. It provides an important input to a wide variety of seismological studies, from seismic hazard to statistical analysis of seismicity and nuclear explosion discrimination. Seismic network operators and observatories routinely estimate standard types of body- and surface-wave magnitudes using established procedures, however, the reported results are often inconsistent due to the differences in the implemented waveform processing schemes. These inconsistencies become more evident with the increasing volumes of recorded data currently faced by seismic networks. With the scope to address the issue, the International Seismological Centre (ISC; www.isc.ac.uk) aims to provide a routine estimation of the standard body- and surface-wave magnitudes using the global waveform data. We take the advantage of the comprehensive event-related information at ISC and the increasing amount of openly available, from the seismological data management centres, waveform data to provide an automatic and reproducible estimation of standard magnitudes following the guidelines of the International Association of Seismology and Physics of the Earth’s Interior (IASPEI) Working Group on Magnitude Measurements.
In this presentation we describe the details of the procedure and examine the results of the magnitude estimations for over 69,000 earthquakes (M > 4.0) reported in the ISC Bulletin for 2016-2020. We will further discuss the performance of the procedure, compare obtained estimated magnitudes with those in the ISC Bulletin and present the advantage of including broadband body- and surface-wave magnitudes.
