A team of researchers from the National Institute of Geophysics and Volcanology (INGV) has analyzed the evolution of ground deformation and seismic activity at Campi Flegrei over the past twenty-three years, highlighting an acceleration of both phenomena over time. The study, published in the journal Communications Earth & Environment (Nature), identifies an exponential relationship between the maximum uplift of the caldera and the cumulative number of seismic events.
The article, titled "Accelerating upper crustal deformation and seismicity of Campi Flegrei caldera (Italy), during the 2000-2023 unrest ," is based on data from the monitoring networks of the Vesuvius Observatory of the INGV. "We adopted a neutral, mathematical approach to represent the evolution of the bradyseismic crisis," explains Augusto Neri, research coordinator. "This allowed us to describe the volcano's behavior and its changes over time, with the aim of improving our understanding of volcanic processes."
Uplift and Seismicity: An Acceleration in Progress
Andrea Bevilacqua, lead author of the study, highlights that the uplift of the caldera's ground, measured at the Rione Terra GNSS station in Pozzuoli, follows a parabolic trend with an average acceleration of 0,7-0,8 cm/year². The earthquake rate , however, shows a superexponential growth, characterized by oscillations with periods ranging from 2 to 5 months for short cycles, and up to 1,5-3 years for longer ones. In recent years, a 10-15% reduction in the duration of these oscillations has been observed.
“These data suggest that periods of lower seismic activity do not necessarily indicate a decrease in the decadal evolution of the volcano,” adds Bevilacqua.
Relationship between uplift and seismicity
One of the most significant aspects of the study is the exponential relationship identified between the uplift of the caldera and the number of earthquakes. “Compared to the bradyseismic crisis of 1982-1984, which showed a linear relationship, today we see an exponential relationship, which has strengthened since 2020,” observes Neri. “This behavior could reflect a progressive deterioration of the mechanical properties of the surface crust, with implications for the probability of future earthquakes.”
An evolving scenario
Flora Giudicepietro, co-author of the study, emphasizes that the data updated to 2024 confirm the trends observed in the period 2000-2023. “If the uplift continues with the same characteristics, we could see an increase in seismic rates higher than those recorded in 2023, as already happened in May 2024.” However, the researcher warns that alternative scenarios cannot be ruled out, such as a reduction in the uplift process, which would lead to a decrease in seismic activity.
Scientific implications and future prospects
The research, although focused on scientific analysis, does not currently have direct implications for civil protection. However, the results represent a crucial contribution to understanding the evolution of the volcano and monitoring potential future scenarios.
This work reinforces the need for constant updating of monitoring data to anticipate any significant changes in the activity of Campi Flegrei.
The analysis of the data on Campi Flegrei seems interesting, but it is not clear how they could affect the daily life of the people who live there. It is important to understand well what these changes mean in the long term, especially for security.
The article talks about important things but sometimes it is difficult to understand because it uses technical terms. It would be useful to have a simpler summary for those who are not familiar with volcanology and seismic monitoring.