INGV reported that eruptive activity continued at Stromboli during 25 September-1 October. Webcam images showed Strombolian activity at three vents in Area N (two at N1 and one at N2), within the upper part of the Sciara del Fuoco, and from three vents in Area C-S (South-Central Crater) in the crater terrace. Explosions of variable intensities occurred at a rate of 7-13 per hour at Area N. Explosions at N2 ejected mainly coarse material (bombs and lapilli), sometimes mixed with ash, up to 150 m above the vents. Spattering occurred at N1 and was intense during 27-28 September, coinciding with the effusion of a lava flow. The flow was first visible at 1428 on 27 September as it moved out of Area N and onto the upper part of the Sciara del Fuoco. By 2107 on 28 September spattering had decreased and the flow was no longer being fed. Spattering again increased and at about 0833 on 3 October lava from Area N flowed onto the upper part of the Sciara del Fuoco.

High-intensity explosions in sector S2 (Area C-S) averaged 6-8 per hour from the vents, ejecting a mix of coarse material as high as 150 m. Material was deposited in a wide area along the crater terrace. Intense spattering was visible on 26 September. The Dipartimento della Protezione Civile maintained the Alert Level at Yellow (the second lowest level on a four-level scale).

Geological Summary. Spectacular incandescent nighttime explosions at Stromboli have long attracted visitors to the "Lighthouse of the Mediterranean" in the NE Aeolian Islands. This volcano has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small island is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period took place between about 13,000 and 5,000 years ago. The active summit vents are located at the head of the Sciara del Fuoco, a prominent scarp that formed about 5,000 years ago due to a series of slope failures which extends to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild Strombolian explosions, sometimes accompanied by lava flows, have been recorded for more than a millennium.

Sources: Sezione di Catania - Osservatorio Etneo (INGV), Dipartimento della Protezione Civile