Sonia Calvari of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) reported that the 2007 eruptive episode at Stromboli started on 27 February and finished on 2 April (BGVN 32:04) Additional details about this eruption can be found in Barberi and others (2009) and Calvari and others (2010). Eruptions later in 2007 and during 2008 will be reported in a later issue; summaries of activity in 2009 and January 2010 are included below.

Activity during 2009. The summit activity in 2009 was very unusual, producing four or five intracrater lava flows. Lava within the crater depression was extruded on 22-25 April, 3 May, and 30 August 2009. On 8 November a major explosion from the vents in the central crater fragmented and destroyed part of the E flank of the cinder cone there. The explosion produced an eruptive column over 350 m high that drifted SE and was soon followed by a lava flow from the widened central vent. The lava flow spread within the crater depression for a few minutes and reached a maximum distance of ~ 60 m. After the 8 November explosion, activity returned to background levels.

Strong seismic activity was recorded on 24 November 2009. Observers saw an explosive eruption cloud and the emission of a lava flow. Ejecta fallout affected the summit area, particularly the Pizzo sopra la Fossa, where numerous volcanic bombs landed. Also affected was the eastern downwind flank, where a layer of pumice was deposited on the beach. The fallout of incandescent material caused some vegetation fires on the E flank. After this explosive activity, seismicity returned to the level previously observed.

Activity during January 2010. According to the INGV website, at 1912 UTC on 4 January 2010, the network of surveillance cameras recorded an explosion that affected the central vent area. During a first phase, coarse pink pyroclastic materials (bombs and possibly lithic particles) were erupted from the entire crater terrace. A second phase followed with the emission of a small ash plume. Beginning at 0757 UTC on 7 January, the IR camera located on the Pizzo sopra la Fossa showed spattering lava in the central portion of the crater, leading to a series of lava flows; the lava stopped around 0100 UTC on 8 January. At 1448 UTC on 10 January, the INGV network of surveillance cameras recorded a strong explosion that affected the N portion of the crater, causing a major fallout of volcanic bombs at Pizzo sopra la Fossa and high on the NE part of the volcano.

References. Barberi, F., Rosi, M., and Scendone, R. (eds), 2009, The 2007 eruption of Stromboli: Journal of Volcanology and Geothermal Research, v. 182, no. 3-4, p. 123-280.

Calvari, S., Lodato, L., Steffke, A., Cristaldi, A., Harris, A.J.L., Spampinato, L., and Boschi, E., 2010, The 2007 Stromboli eruption: Event chronology and effusion rates using thermal infrared data: Journal Geophysical Research, Solid Earth, 115, B4, B04201, doi:10.1029/2009JB006478.

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.

Information Contacts: Sonia Calvari, Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione di Catania, Piazza Roma 2, 95123 Catania, Italy (URL: http://www.ct.ingv.it/).