A new study by the INGV and the University of Catania has analyzed the deep structure of Etna and the link between seismic activity and the rise of magma, revealing new details on the internal dynamics of the volcano.
The hidden heart of Etna has been the subject of a joint study by theNational Institute of Geophysics and Volcanology (INGV) and University of CataniaThe research results have allowed us to reconstruct the dense network of active faults present under the volcano. By analyzing more than 15.000 earthquakes over a period of about two decades, researchers have traced the structures that drive crustal deformation and their interaction with magma movements.
Published in the international journal Scientific Reports, the study entitled “Earthquake clustering and structural modeling unravel volcano-tectonic complexity beneath Mount Etna” highlights how the most intense eruptions, such as those of 2018 and 2021, are preceded by a significant release of seismic energy that affects the entire geological architecture of the area up to depths of about 30 km. During eruptive events, the pressure exerted by the magma in the layers of the crust can activate faults even at considerable distances and depths from the summit craters.
“We observed that the magma, rising towards the surface, exerts a pressure that interferes with the fault system, significantly modifying the equilibrium of the Earth's crust,” explains Luciano Scarfi, first author of the study and researcher at INGV. “It is not just a phenomenon localized to the crater area, but a mechanism that involves the entire volcanic system”.
Of particular interest is the dynamics of the eastern flank of Etna, known for its slow and constant sliding towards the Ionian Sea. Research shows that this movement is not uniform, but occurs along different structures, triggered by a combination of ancient faults, magmatic pressures and surface subsidence.
“We are faced with a complex system”, he adds Giovanni Barreca, co-author of the study and researcher at the University of Catania. “The volcano’s short-term seismotectonics are governed by the reactivation of structures inherited from the long geological and tectonic history of the area. Many of these do not correspond to faults already known on the surface.”
According to the research team, which also includes Carmelo Cassisi e Horst Langer, researchers at INGV, the new evidence of the internal structure of Etna represents an important step forward also in the evaluation of volcanic risk.
“Our methodology, which combines three-dimensional models, advanced seismological techniques and the use of data mining algorithms, can be applied to other active volcanoes located in complex geological contexts”, the authors conclude.
The study not only improves the ability to interpret the behavior of Etna, but also provides a replicable scientific tool for analyzing other volcanic systems around the world.
Fig.1 – Spatial distribution of seismic clusters identified through advanced analysis: (A) map representation with event location and (B) three-dimensional visualization highlighting their depth and relative arrangement.
Fig.2 – 3D seismic-tectonic model with a view oriented towards the north-east, which highlights the correlation between the seismic clusters and the main geological structures of the study area.