In addition, 12 induced events, i.e. man-made events (geothermal exploitation, extraction of rock masses in mines, etc.), 367 quarry explosions and at least 9 explosions at sea linked to Controlled destruction of WWI and WWII bombs by Belgian, Dutch or French armies has been recorded. The two most significant seismic events measured in 2021 by the observatory occurred on January 2 and 14, and both had a local magnitude of 2.6 on the Richter scale, which traditionally has nine steps. They were felt from Rott in the German Eifel Hills to Eupen. The greatest seismic activity measured by the ORB occurred within a 1.5 km radius of the town of Rott. During this seismic sequence felt as far as Belgium, 126 earthquakes were located at an average depth of 9.7 km below the Earth’s surface. Seven events in this sequence were felt by the local population.
The largest earthquakes recorded on Belgian territory in 2021 took place on June 20 in Dampremy near Charleroi and on August 28 in Baelen near Eupen. These two events had a local magnitude of 1.7 and were not felt by the local population. The twelve induced events measured are linked to a deep geothermal project in Dessel, in the province of Antwerp.
In 2020, 52 earthquakes occurred in Belgium and neighboring regions. The largest earthquake was that of May 5, 2020 in Modave, with a local magnitude of 1.7.
The seismic monitoring network of the Royal Observatory of Belgium currently includes 30 seismometric stations and 18 accelerometric stations.