Rome, April 10, 2018
Seismic event in the province of Macerata, Ml 4.7, 10 April 2018
This morning, at 05:11 Italian time of 10 April 2018, the National Institute of Geophysics and Volcanology (INGV) localized an earthquake of magnitude ML 4.7 (Mw 4.6) in the province of Macerata, 2 km from Muccia (MC), at a depth of 9 km. The municipalities closest to the epicenter are: Muccia, Pieve Torina, Pievebovigliana.
This earthquake, like the events that have occurred in the last few days in this area, fall within the area of the seismic sequence that began on August 24, 2016 with the magnitude Mw 6.0 event that occurred near Amatrice and Accumoli (RI) and culminated with seismic event of October 30, 2016 of magnitude Mw 6.5. This sequence has gradually developed involving a large strip of the central Apennines, an area of about 1200 km2, extended for about 80 km in the NNW-SSE direction and about 15-20 km wide, from the province of Macerata, in the Marches, to the province of L'Aquila, in Abruzzo.
The area affected by the earthquakes of recent days was activated at the end of October 2016, between 26 and 30 October, when some of the strongest seismic events of the sequence occurred: those of 26 October with magnitude Mw 5.4 and magnitude Mw 5.9 and that of magnitude Mw 6.5 of 30 October 2016.
If one considers the temporal evolution of the overall seismic sequence and the energy released by all seismic events, it can be seen that in the last months of 2017 an average of 30-40 events were localized per day. In early March 2018, seismicity increased, exceeding 100 events per day in one case and also in these first days of April it exceeded 140 events per day. This increase in seismicity is mainly concentrated in the northernmost sector of the fault system activated in 2016, near the municipalities of Muccia, Pieve Torina, Pievebovigliana (MC). Today's event therefore represents an increase in energy released compared to the last two months of the sequence.
According to the accelerometric data, the event has peak accelerations which correspond to an instrumental intensity on rocky ground equal to the VI degree of the MCS scale (http://shakemap.rm.ingv.it).
The event was felt in a large area, particularly in the area north-east of the epicenter, in the provinces of Macerata, Ancona, Pesaro, in Umbria, in Lazio and, to a lesser extent, in Rome, as evidenced by the 590 questionnaires completed so far on http://www.haisentitoilterremoto.it/ and from the seismic effect map in MCS scale (Mercalli-Cancani-Sieberg) which shows the distribution of earthquake effects on the territory.
Map of seismic effect in MCS scale (Mercalli-Cancani-Sieberg) showing the distribution of the effects of the earthquake on the territory as reconstructed from the online questionnaires. The map contains a legend (on the right). The purple star indicates the epicenter of the earthquake, the colored circles refer to the intensities associated with each municipality. The caption above shows the characteristics of the earthquake: date, magnitude (ML), depth (Prof) and local time. The number of questionnaires processed to obtain the map itself is also indicated.
For more information on this event: http://cnt.rm.ingv.it/event/18673351
At the moment (07:50) another 18 events of magnitude Ml greater than 2.0 have been located, two of which had a magnitude of 3.5
Link to the INGVterremoti Blog: