There are 16,095 earthquakes located on the Italian territory and in the neighboring areas of the National Seismic Network in the course of 2021: an average of 44 earthquakes per day, or one event every half hour, with Sicily, Umbria and Marche among the most affected regions.
The balance is drawn up by the National Institute of Geophysics and Volcanology (Ingv).
The number of earthquakes located in Italy in 2021 is slightly lower than in 2020 (16,597) and has remained stable since 2019 (16,584). Numbers lower than those recorded in the years 2016-2017-2018, characterized by the seismic sequence in central Italy. The contribution of this sequence that began on 24 August 2016, in terms of the number of events, is however important also in 2021, representing about 30% of the total seismicity in Italy.
"The trend of the last three years was also confirmed in 2021, with the strongest earthquakes located outside the Italian territory - says Alessandro Amato, Ingv seismologist - As can be seen from the map published on INGVterremoti, the seismic events that have recorded a magnitude equal to or greater than 5.0 took place in Algeria, Croatia and the Adriatic Sea, even if some of them had resentment also in the Italian territory ".
“The first Italian earthquake of 2021 occurred in the Modena area, in Pavullo nel Frignano, 1 hour and 3 minutes after the start of the new year.
The last, however, we located in Sefro, in the province of Macerata, less than half an hour from midnight: both recorded a magnitude of less than 2.5 ”explains Maurizio Pignone, geologist of Ingv.
“Sardinia is confirmed as the region with the lowest number of earthquakes, while Sicily has had over 80 events of magnitude equal to or greater than 2.5, more than all other regions. If, however, we also counted very small earthquakes, the primacy would be conditioned by the density of the seismic network and Marche and Umbria would “win” with approximately 3,000 and 5,000 events respectively ”. The strongest earthquake occurred in Sicily, near Motta Sant'Anastasia, on December 23, 2021, within a seismic swarm with over 50 events in three days and was characterized by a magnitude 4.3. The smallest, however, was recorded near Gubbio on August 13, 2021 with a magnitude that in this case was 0.0 (since the Richter scale can also have negative values),located by the National Seismic Network in an area of Italy where the sensitivity of the network is maximum.