In relation to the seismic swarm that has affected the Campi Flegrei area since the evening of July 31st, the President of theIstituto Nazionale di Geofisica e Vulcanologia (INGV), Fabio Florindo, expresses his closeness to the citizens who are experiencing hours of understandable discomfort and concern following the magnitude 4.7 earthquake recorded yesterday evening.
The INGV is constantly monitoring the evolution of the seismic swarm. The Vesuvius Observatory's operations room is fully operational, and all personnel involved are engaged in real-time analysis of data from the seismic, geodetic, and geochemical monitoring networks, ensuring a constant flow of information to the Civil Protection Department, the relevant institutions, and the public.
President Florindo convened the INGV Crisis Unit, during which scientific updates and assessments of the evolution of the current phenomena were shared.
The magnitude 4.7 earthquake represents the strongest recorded during the current phase of bradyseism in the Campi Flegrei. It is a significant event that demonstrates how the ongoing ground deformation process can produce earthquakes of significant energy. However, a single earthquake, even of this magnitude, is not sufficient to indicate a change in the state of the volcanic system.
Scientific assessments are not based on the observation of a single parameter, but on an integrated analysis of the entire monitoring network: seismicity, ground deformation, gas emissions, and all other geophysical and geochemical indicators. It is the overall evolution of this data that allows us to assess whether significant changes in the phenomenon have occurred.
In the coming hours, the swarm may continue with further earthquakes, as typically occurs after an event of this magnitude. At this time, it is not possible to predict with certainty either the number or the strength of any subsequent tremors. For this very reason, continuous monitoring is a fundamental tool for promptly identifying any changes in the various parameters of the geophysical framework.
I would like to extend my sincere thanks to the researchers, technologists, technicians, and all the staff at the Vesuvius Observatory and the INGV who, since yesterday evening, have been working with professionalism, expertise, and a sense of responsibility to ensure continuous monitoring of the phenomenon and provide the authorities and the public with reliable and timely scientific data. Their commitment represents an essential service to the country.
I fully understand the public's concern. A shock of this energy was felt very strongly and caused panic, damage, and disruption for the population. For this very reason, it is essential to rely exclusively on information released by the competent institutions and the scientific community, avoiding interpretations or unverified reports that risk needlessly fueling alarm.
Scientific research has the task of observing, measuring, and interpreting natural phenomena with the utmost rigor, providing objective evidence to support authorities' decisions. We will continue to do so with transparency, timeliness, and a sense of responsibility, placing our expertise at the service of the country.
The INGV will continue to provide timely updates on ongoing phenomena through its institutional channels and those of the Department of Civil Protection.
The INGV is constantly monitoring the evolution of the seismic swarm. The Vesuvius Observatory's operations room is fully operational, and all personnel involved are engaged in real-time analysis of data from the seismic, geodetic, and geochemical monitoring networks, ensuring a constant flow of information to the Civil Protection Department, the relevant institutions, and the public.
President Florindo convened the INGV Crisis Unit, during which scientific updates and assessments of the evolution of the current phenomena were shared.
The magnitude 4.7 earthquake represents the strongest recorded during the current phase of bradyseism in the Campi Flegrei. It is a significant event that demonstrates how the ongoing ground deformation process can produce earthquakes of significant energy. However, a single earthquake, even of this magnitude, is not sufficient to indicate a change in the state of the volcanic system.
Scientific assessments are not based on the observation of a single parameter, but on an integrated analysis of the entire monitoring network: seismicity, ground deformation, gas emissions, and all other geophysical and geochemical indicators. It is the overall evolution of this data that allows us to assess whether significant changes in the phenomenon have occurred.
In the coming hours, the swarm may continue with further earthquakes, as typically occurs after an event of this magnitude. At this time, it is not possible to predict with certainty either the number or the strength of any subsequent tremors. For this very reason, continuous monitoring is a fundamental tool for promptly identifying any changes in the various parameters of the geophysical framework.
I would like to extend my sincere thanks to the researchers, technologists, technicians, and all the staff at the Vesuvius Observatory and the INGV who, since yesterday evening, have been working with professionalism, expertise, and a sense of responsibility to ensure continuous monitoring of the phenomenon and provide the authorities and the public with reliable and timely scientific data. Their commitment represents an essential service to the country.
I fully understand the public's concern. A shock of this energy was felt very strongly and caused panic, damage, and disruption for the population. For this very reason, it is essential to rely exclusively on information released by the competent institutions and the scientific community, avoiding interpretations or unverified reports that risk needlessly fueling alarm.
Scientific research has the task of observing, measuring, and interpreting natural phenomena with the utmost rigor, providing objective evidence to support authorities' decisions. We will continue to do so with transparency, timeliness, and a sense of responsibility, placing our expertise at the service of the country.
The INGV will continue to provide timely updates on ongoing phenomena through its institutional channels and those of the Department of Civil Protection.
Figure 1: The image shows the epicentral and hypocentral distribution of seismic events localized by the Operations Room of the Vesuvius Observatory in the Campi Flegrei area between July 31 and August 1, 2026. 
Figure 2: The image shows the spatial distribution of the maximum ground acceleration (PGA) values, expressed as a percentage of the gravitational acceleration (%g), recorded by seismic stations in the Campi Flegrei area for the magnitude Md 4.7 event at 19:46 PM on July 31, 2026. As can be seen from the map, the earthquake caused strong shaking with localized accelerations that exceeded 80% of g.