A new "major explosion" was recorded today, April 27, on the Stromboli volcano by the National Institute of Geophysics and Volcanology (Ingv), after the intense explosive sequence that last April 24 involved the mouths of the central-southern area placed on the crater terrace. At 00:53:50 (local time) the first strong explosion which affected the vent called "N2", located in the northern area of the Stromboli crater terrace (frame ADG). The duration of this event was approximately 5 seconds. The coarse products, both lithic (fragments of already consolidated lava) and pyroclastic (shreds of incandescent magma), were mainly distributed in a west-northwest (W-NW) direction, covering the upper part of the Sciara del Fuoco and rolling abundantly along its slopes (frame BEH).
Seventeen seconds after the first explosion, at 00:54:07, a modest fountaining activity began (continuous jet of lava, in this case expelled at a height of the order of a few tens of metres) which gradually it passed to discontinuous Strombolian explosions (spattering), interspersed with some explosions of ash and incandescent material of low intensity which reached a maximum height of about 80 m.
The entire explosive sequence lasted about three minutes. Subsequently, the volcano returned to producing its normal Strombolian activity.
As known, these explosive events are characterized by greater violence than the "ordinary" Strombolian activity which, on the other hand, characterizes this volcano in everyday life.
These are unpredictable events that can cause the fall of volcanic bombs, lapilli and rock fragments, even quite large ones, in the summit portion of the volcano, and which are therefore potentially dangerous for any observer passing through the areas of the Pizzo sopra la Fossa belvedere. or along the paths that lead there.
However, the explosion that took place yesterday evening, perhaps due to the wind, produced an abundant fallout of incandescent material only inside the crater terrace and along the Sciara del Fuoco, sparing the Pizzo area.
Stromboli's eruptive activity is constantly monitored by INGV through the observational, geophysical and geochemical systems managed by the Sections of Catania, Naples and Palermo.
Figure 1 - Explosion of 27 April 2018. Significant frames taken by the infrared spectrum camera of the Pizzo above the Fossa. The time displayed in the images corresponds to UTC (Coordinated Universal Time).
Figure 2 - Explosion of April 27, 2018. Significant frames taken by the infrared spectrum camera of Quota 400. The time displayed in the images corresponds to UTC (Coordinated Universal Time).
Figure 3 - Explosion of April 27, 2018. Significant frames taken by the visible spectrum camera of Quota 400. The time displayed in the images corresponds to UTC (Coordinated Universal Time).