At 9.29 (Italian time), an explosive sequence took place on Stromboli lasting a total of about 3 minutes, with characteristics similar to the one that occurred on 23 October last. The analysis of the images from the thermal and visible surveillance cameras showed that the sequence began with an event of greater intensity from the central-southern crater area, followed by some minor explosions in the following minutes (Fig. 1).
Fig 1 – Initial phases of the explosive sequence filmed by the thermal (SQT) and visible (SQV) cameras located at an altitude of 400m.
The sequence generated the fallout of abundant coarse pyroclastic material on the Sciara del fuoco and in the direction of Pizzo sopra la Fossa, with a dense plume of ash rapidly dispersed by the wind on the southern slope of the volcano.
From the analysis of the seismic tracing, it was possible to highlight that it was a typical explosive sequence, characterized by a series of events, followed by a persistent signal (tremor) lasting a few minutes. This phenomenon is not necessarily linked to the ascent of new magma.
In the hours following the sequence, no other significant phenomena occurred. Even the seismic parameters have returned to the situation prior to the event.
An inspection is expected in the coming days to characterize the event in more detail.
At present, it is not possible to exclude that events of this type could also be repeated in the short term.