Magma is accumulating at shallow depths, increasing the risk of an eruption at the Campi Flegrei

A new study highlights that the rise of magma up to 4 kilometers is the main driver of the ongoing bradyseismic crisis

ROME – The Campi Flegrei volcano has shown signs of a progressive accumulation of magma at relatively shallow depths.Experts warn that, although there are currently no signs of an imminent eruption, the possible continued accumulation of magma and increased pressure underground represent a risk that must continue to be monitored and managed with great care.

Understand whether seismic activity, soil deformation and gas emission, phenomena which have progressively increased since 2007 due to the ongoing bradyseism in the Campi Flegrei volcano, involve the movement or accumulation of magma in depth and, therefore, trace it evolution over time.
These are the objectives achieved by an international team of researchers led by the National Institute of Geophysics and Volcanology (Ingv), in collaboration with the Roma Tre University and the Université de Genève, as part of the “LOVE-CF” project funded by Ingv for the multidisciplinary investigation of the Campi Flegrei.

The results of the study are reported in the article “Tracking the 2007-2023 magma-driven unrest at Campi Flegrei caldera (Italy)”, recently published in the journal Nature – Communications of Earth and Environment, which addresses these important aspects to define the dynamics and the current state of a volcano in an area of ​​high population density.

For years, scientists have carefully monitored the activity of the Campi Flegrei, the vast volcanic caldera located west of Naples, the volcano known in recent decades for bradyseismic crises.Using advanced techniques, such as geodesy, numerical simulations and petrology, the researchers managed to map the movement of magma in the depths of the caldera over 16 years, from 2007 to 2023, i.e. from the beginning of the new bradyseismic phase of the volcano that still lasts today. The analysis highlights that the rise of magma at depths of less than 8 kilometers is the main driver of the ongoing activity, characterized by a slow and constant lifting of the ground, which has reached approximately 1.3 meters in the Rione Terra of Pozzuoli since 2006 to present.

Considering different scenarios, the researchers deduced that the deformation source is progressively shallower over the years, from about 6 km up to about 4 km deep.This source is the result of the ascent of magma and magmatic gases from the main accumulation zone, 8 km deep, to lower depths.Furthermore, the rise of magma and magmatic gases has contributed to the intensification of seismic activity and the increase in gas emission phenomena, in particular in the Solfatara area, which iconographically represents one of the main volcanic manifestations of the caldera.

“It is essential to constantly monitor the behavior of this volcano, especially considering that it is located in one of the most densely populated areas of Europe,” declares Elisa Trasatti, researcher at the INGV National Earthquake Observatory and coordinator of the research group.
“In recent decades, the ground deformation measurement network using GNSS has reached a very high level of technological development due to the number of stations throughout the volcanic area, and the reliability of data processing, which is acquired continuously. and processed daily.Furthermore - continues the researcher - the satellite data allowed a reconstruction with great areal coverage.Thanks to the high quality of the data, it was possible to develop advanced models to identify the cause of the monitored deformations.This allowed us to take a further step in determining the origin of the activity of the Campi Flegrei".

Mauro Antonio Di Vito, director of the INGV Vesuvian Observatory and co-author of the study, explains:“Any statement regarding the activity of the Campi Flegrei must be carefully considered.Although it is not possible to define with certainty the presence of magma at around 4 km depth, the study establishes for the first time that magma, rising from 8 km, is the main driver of the activity underway at Campi Flegrei.Although there are currently no imminent signs of an eruption, the continued accumulation of magma and increased pressure underground represent a risk that should not be ignored."

Valerio Acocella, professor at Roma Tre University, research associate at INGV and co-author of the study, highlights:“This study provides important elements to better understand and constrain the current state of the Campi Flegrei magmatic system”.It also underlines the importance of international collaboration:“The study also demonstrates how important it is to integrate different disciplines and use the skills of different institutions to address complex problems such as that of the Campi Flegrei.Only through a multidisciplinary approach can we hope to fully understand the dynamics of volcanoes."

Scientists recall that the volcano is constantly monitored through a dense multi-parameter network which allows detecting even the slightest changes in the caldera.“The most recent data, from 2023 to today, show similarities with what was observed in the previous 16 years, with a slight intensification of the demonstrations.Therefore – concludes Di Vito – at the moment there are no reasons to believe that the magmatic activity is not still continuing as defined in the study.We are constantly in contact with the Civil Protection to ensure that every small development is followed with the utmost attention."