Enriching the GEOFON seismic catalogue with automatic energy magnitude estimations
Abstract. We present a seismic catalogue including energy magnitude Me estimated from P-waves recorded at teleseismic distances in the range 20o ≤ Δ ≤ 98o and for depths less than 80 km. The catalogue is built starting from the event catalogue disseminated by GEOFON, considering 6349 earthquakes with moment magnitude Mw ≥ 5 occurring between 2011 and 2023. Magnitudes are computed using 1031396 freely available waveforms archived in EIDA and IRIS repositories, retrieved through standard FDSN webservices (https://www.fdsn.org/webservices/). A reduced, high quality catalogue for events with Mw ≥ 5.8 and from which stations and events with only few recordings were removed forms the basis of a detailed analysis of the residuals of individual station measurements, which are decomposed into station and event specific terms, and a term accounting for remaining variability. The derived Me values are compared to Mw computed by GEOFON and with the Me values calculated by IRIS. Software and tools developed for downloading and processing waveforms for bulk analysis and an add-on for SeisComP for real-time assessment of Me in a monitoring context are also provided alongside the catalogue. The SeisComP add-on is part of the GEOFON routine processing since December 2021 to compute and disseminate Me for major events via the existing services.
Viewed (geographical distribution)