FENCAT—an update of the Fennoscandian earthquake catalogue

The Fennoscandian earthquake catalogue (FENCAT) assembles data on the natural seismicity in Fennoscandia, Northern Europe. We present an updated and standardized version of the catalogue originally published in the early 1990s. New instrumental data are recorded by the seismic networks of Denmark, Estonia, Finland, Norway and Sweden, and analysed by the Geological Survey of Denmark and Greenland, the Geological Survey of Estonia, the University of Helsinki in Finland, the University of Bergen and the NORSAR research foundation in Norway and Uppsala University in Sweden. The updated catalogue provides the available earthquake parameters in a brief, user-friendly version: origin time, source coordinates, focal depth, macroseismic data (maximum intensity and radius of the area of perceptibility), up to three observed magnitudes, seismic moment estimate and a standardized moment-related magnitude, mW(HEL), for each event. The standardized magnitude is defined in this paper and its relation to other magnitude scales is provided. Suspected non-earthquakes (e.g. frost events, explosions, human-induced events) have been removed. The standardized event magnitudes range from mW(HEL) −1.0 to 6.2. To enable the usage of earthquake data in a large variety of seismological, geological and earthquake engineering investigations, the data are not truncated at the low-magnitude end.The updated catalogue, FENCAT (2021), contains about 23 000 earthquakes for the period 1467–2021 in an area bounded by 54–75°N latitudes and 0–45°E longitudes. The completeness and quality of the earthquake solutions is best within the areal coverage of the above-mentioned networks.