Last year there were about 3000 more events than in 2013, an average of 66 earthquakes a day, almost one every 20 minutes, even if two-thirds of the total were very low-magnitude. Only 3% of the earthquakes recorded in the year were felt by the population. The central Apennine belt was the area with the highest seismicity rate of the whole national territory by number of events. This is what emerges from the article "Sismic Italy, the earthquakes of 2014", published on the IngvTerremoti Blog together with the Map Journal of seismicity.
There are 24.312 earthquakes located in 2014 by the National Seismic Network (RSN) of the National Institute of Geophysics and Volcanology (Ingv), about 3000 more events than in 2013, an average of 66 earthquakes a day, almost one earthquake every 20 minutes. These are just some of the data published on the INGVterremoti blog of the National Institute of Geophysics and Volcanology in the special "Sismic Italy, the earthquakes of 2014" (http://wp.me/pQl3O-1Iz). The article, a usual appointment at the beginning of each year, illustrates the seismic situation in Italy in the previous year, using data from the Rsn.
“From the 2014 seismicity survey”, says Franco Mele, seismologist of the Ingv National Earthquake Center (Cnt-Ingv), “it emerges that earthquakes of magnitude 1.5 or higher were less than a third of the total, a good 7.169. While events of magnitude 2.5 and above (those for which the Institute sends a communication to the Civil Protection Department - Dpc), there were a total of 731 (3% of the total) with an average of 2 communications per day".
Although the number of earthquakes in 2014 was higher than in previous years, no events with a magnitude greater than or equal to 5.0 were recorded. Two instead those of higher magnitude, Mw 4.7, both detected in April three days apart, located respectively in the Ionian Sea off the eastern Calabrian coast (April 5) and in the Cottian Alps (April 7).
"To follow the space-time trend of last year's seismicity, a video was made (http://wp.me/aQl3O-1JF) which shows, week by week, the distribution of the over twenty-four thousand earthquakes recorded by the Rsn”, adds Mele. "The video shows that even in 2014 most of the seismicity was manifested through hundreds of seismic sequences: of these, 100 consisting of at least 5 events each, some characterized by a few short-term events, others with a duration of several months, and over a thousand recorded earthquakes”.
The central Apennine band, which extends northwards from the city of L'Aquila, skirts the province of Rieti and continues in the Umbria-Marche Apennines up to Città di Castello (PG) and Sansepolcro (AR), was the area with the highest seismicity rate of the entire national territory (in terms of number of events).
“In this Apennine sector, seismicity has had an almost continuous activity concentrated in the seismic sequence of Gubbio (PG), which has had periods of great activity especially in the first months of the year. In total there were over 12.000 earthquakes recorded in this area, half of all the events recorded by the Rsn, although the vast majority of these had a very low magnitude", comments Maurizio Pignone, geologist of the Cnt-Ingv. New this year, concludes Pignone, "a Map Journal, capable of grouping all the Italia Sismica articles of 2014 thanks to an application that integrates the interactive maps of earthquakes (with various functionalities for displaying and querying seismic events and relative information on magnitude, date/time and depth) with the contents (photos, texts, images) of the individual articles". The Map Journal of the 2014 seismicity can be directly reached at the following address: http://bit.ly/16GfO34.
Rome 9 February 2015