Several calls reached the firefighters after the two strong earthquakes felt today Monday 20 May in Naples. The first at 7.51pm followed by a much more intense one at 8.10pm. According to the first calculations by the Institute of Geophysics and Volcanology, the first earthquake had a magnitude of 3.5, a power in line with the intense and persistent seismic swarm underway in the caldera of the Campi Flegrei supervolcano, the area within which the epicenter of the earthquake falls. earthquake today.
The second shock at 8.10pm was instead assessed as having a magnitude of 4.4, much more intense. The epicenter was identified by INGV sensors at a depth of 3 kilometers, an area in which the rise of high-pressure fluids coming from the underground magmatic basin was documented as we explained here.
Immediately after the main shock, other smaller shocks were clearly felt: the seismic swarm has at least 20 small earthquakes (some not felt by the population) and is still ongoing. The strongest tremor was also felt on the island of Procida.
Firefighter teams are working in the area to verify reports of cracks and falling cornices in buildings.
#Naplesshook #earthquake the highest of magnitude 4.4 recorded at 8.10 pm in the area #CampiFlegrei: arrived at the operations room of the #fire fighters some reports of cracks and falling cornices in buildings. Teams in the area for checks (#May, 20th 8.40pm) pic.twitter.com/IFFapvKjVu
— Fire Brigade (@vigilidelfuoco) May 20, 2024
With an earthquake of magnitude 4.4, today's seismic swarm becomes the most significant event since the beginning of the new activity of the caldera which began in 2005. For about twenty years, in fact, the Campi Flegrei area has been affected by a bradyseismic crisis characterized by the ascent and from the accumulation of magmatic gases (between 2 and 3 kilometers deep), and of magna at a depth of 5 kilometers.
The Phlegraean fields in yellow alarm code
Does this mean we are close to an eruption? At present there is no indication in this sense: the situation in the caldera area is under close monitoring after last September's earthquake which, with a magnitude of 4.2, was the most powerful in the last 40 years. Now this record will be updated. The maximum ground acceleration induced by the earthquake and recorded by the accelerometers recorded a value of 0.35 g near the epicenter, a decidedly notable intensity, typical of territories at high seismic risk. Structures that are not properly designed can be damaged.
In the last month, civil protection had not adjusted the population alert system which remained at code yellow, however it should be noted that the raising of the ground in the Campi Flegrei has proceeded in the last month at a rate of 20 millimetres, double compared to January this year.
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