The Belgian gravimetric database consists of 69,000 measurements, made using relative spring gravimeters. This database is managed by the Royal Observatory of Belgium since 1925. Two superconducting gravimeters measure elusive gravity variations at the stations of Membach and Rochefort, with a precision better than 1E-10 of gravity at the surface of the Earth (g). Since 1996, an absolute gravimeter performs repeated gravity measurements at selected sites, with an accuracy of 1E-9 g.

This web service provides a display of the Administrative Units - INSPIRE datase This webservice complies with the INSPIRE specifications.

The Belgian seismic network of the Royal Observatory of Belgium (ROB), with about 45 permanent stations, is mainly dedicated to the monitoring and the scientific study of the seismic activity in Belgium. The ROB is also managing 3 stations in the Grand-Duchy of Luxemburg (in cooperation with the European Center for Geodynamics and Seismology). Earthquakes worldwide with magnitude greater than 4.5 – 5.0 are routinely recorded by the Belgian seismic network. The measurements on these recordings are sent to international seismological centers (EMSC and ISC) where data from stations worldwide are analyzed to furnish a global catalogue of earthquakes and phase arrival time models. We also provide real-time seismic signals from some Belgian stations to data exchange centers like ORFEUS (Observatories and Research Facilities for European Seismology) and IRIS (Incorporated Research Institutions for Seismology).To complement the seismic network, the Belgian accelerometric network was installed early in the 2000ies to furnish reliable data when strong ground motions saturate traditional seismometers. This network consists of 19 stations, is sensitive to accelerations of 1E-5 g (g is gravity at the Earth’s surface) and is an important tool for professionals in the field of earthquake engineering and engineering seismology (seismic hazard assessment). Currently, since 2014 the service is installing another network (“AcceleROB“) of 90 low-cost accelerometers. These sensors are calibrated to be sensitive to accelerations of 1E-3 g, which should be observed during any earthquake of local magnitude ML=3 or larger.