The unified catalogue of earthquakes in central, northern, and northwestern Europe (CENEC)-updated and expanded to the last millennium

New databases motivate improvements and extensions of the catalogue by Grunthal and Wahlstrom (J Seismol 7:507-531, 2003a) - G&W03 - of earthquakes in central, northern, and northwestern Europe with M (w) a parts per thousand yenaEuro parts per thousand 3.50. Data from over 30 regional catalogues, the International Seismological Centre and U.S. National Earthquake Information Center bulletins for the NE Atlantic Ocean, and many special studies were analysed, largely along the lines of the previous study. Non-tectonic, non-seismic, and non-existing as well as duplicate events were identified and removed according to our current stage of knowledge. If not given by the original source, the moment magnitude, M (w), was calculated for each event with a specified epicentral location and a given strength measure (i.e., an original magnitude of any type or, for onshore events only, an intensity). The calculations follow transformation relations derived in the present or in our previous study. The investigated area is subdivided into 22 polygons, in each of which one or more local catalogues, supplemented by data from special studies, are used. If more than one catalogue lists an event, one entry was selected according to a priority algorithm specific for each polygon. If the selected catalogue entry contains more than one strength type, one was selected for the M (w) calculation according to another priority scheme. The final catalogue, CENEC, is confined to the time period 1000-2004 and magnitudes M (w) a parts per thousand yenaEuro parts per thousand 3.50. This is an extension of the time period covered by G&W03 (1300-1993). The number of events has increased from about 5,000 to about 8,000. For each entry, available information on the date, time, location (including focal depth), intensity I (0), magnitude M (w), and source (i.e., the local catalogue or special study) are given. The strength type and value from which M (w) was calculated are also indicated. The catalogue is available on the website of the GFZ German Research Centre of Geosciences.