The researchers of the National Institute of Geophysics and Volcanology (INGV) managed to reconstruct the mechanism at the origin of the Pyroclastic avalanches (or pyroclastic currents), High speed and temperature flows consisting of gases, ashes and rocky fragments, which periodically take place onEtna. In particular, the study, published in the magazine Nature Communications Earth & Environmentwas based on the analysis of the pyroclastic avalanche that took place the February 10, 2022.
These events are potentially very dangerousdespite Etna’s eruptions are generally considered “quiet”. The most recent took place the June 2, 2025with one New pyroclastic avalanche which occurred on the north-eastern side of the South-east crater Etna.
The study of pyroclastic avalanches on Etna has made it possible to create one danger of dangerousness updated of the summit area of Etna, indispensable for Improve prevention of volcanic risk.
What are the pyroclastic avalanches
The pyroclastic currents They are one of the potentially most dangerous phenomena associated with volcanic eruptions. Usually accompany the explosive eruptions more violent than volcanoes fed by Silice and viscous magmas. These are sudden Flows of gas, ashes and rocky fragments Which move at very high speed and temperature along the sides of the volcanoes, overwhelming everything they encounter. These flows are the consequence of the collapse of eruptive columnsOf explosions from lateral craters or of the collapse of lava domes. However, even the eruptions powered by Basaltic magma, poor in silica and fluidlike those of Etna, are able in some cases of originating dangerous pyroclastic currents. In these cases we speak more precisely than Pyroclastic avalanchesbecause mainly due to collapse for gravity of deposits of pyroclastic materials (rocky fragments of various sizes) present on the slopes of the volcano. During its eruptive history, theEtna has often given rise to pyroclastic avalanches, which have mostly involved the South-east craterthe youngest and most active among the top craters of Etna.
The study of the pyroclastic avalanches of Etna
Over time, the volcanic activity of Etna has meant that the South-east craterwhich was initially a depression, became a Growth -sized coneconsisting of pyroclastic materials. This growth was accompanied by the opening of New eruptive mouths and cracks in the cone. The structure has thus become increasingly unstable and frequent paroxysmsthat is, the most intense explosive events have caused collapses and generated Pyroclastic avalanches above all Starting from 2020. The most significant and potentially dangerous episode occurred the February 10, 2022 And the study of Ingv researchers was based on it, who managed to reconstruct the dynamics. The researchers used a multidisciplinary approach By integrating the analysis of avalanche materials, data from remotection, video recording of eruptive activity and numerical modeling.
From the analysis it turned out that the pyroclastic avalanche of 10 February 2022 was caused by collapse of the side of the cone of the South-East crater due, as he declares Daniele AndronicoIngv researcher and co-author of the study, “al rapid accumulation of unstable materialcombined with high residual temperatures and alteration of surface deposits“. The flow that derived from it involved a volume of approx one million cubic meters of material And he left a deep scar on the volcano. These studies have made it possible to create a danger of dangerousness Updated in the top area of Etna, fundamental for better volcanic risk prevention.
