Report on Stromboli (Italy) — July 2003
Bulletin of the Global Volcanism Network, vol. 28, no. 7 (July 2003)
Managing Editor: Edward Venzke.
Stromboli (Italy) Flank eruption finished as of 22 July; activity resumed at summit craters on 17 April
Please cite this report as:
Global Volcanism Program, 2003. Report on Stromboli (Italy). In: Venzke, E (ed.), Bulletin of the Global Volcanism Network, 28:7. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.BGVN200307-211040.
38.789°N, 15.213°E; summit elev. 924 m
All times are local (unless otherwise noted)
Effusion of lava from vents located at about 600 m elevation on the upper eastern corner of the Sciara del Fuoco decreased in early June and completely stopped between 21 and 22 July. The decreasing effusion rate caused shorter lava flows, which during July did not spread below 600 m elevation. The upper part of the lava flow field, formed since 15 February on the upper Sciara del Fuoco, reached an estimated thickness of more than 50 m as a result of the slower rate.
[After] the 5 April eruption (BGVN 28:04), the summit craters of the volcano [were] blocked by fallout debris obstructing the conduit. [By 17 April the blockage was apparently cleared because] small, occasional, and short-lived explosions of juvenile, hot material were observed at Crater 3 (the SW crater) [that day] during a helicopter survey with a hand-held thermal camera, and at Crater 1 (the NE crater) on 3 May from the SAR fixed camera located at 400 m on the eastern rim of the Sciara del Fuoco.
Strombolian activity from Crater 1 (NE crater) became more frequent and intense in June, and almost continuous in July, with spatter often falling outside the crater. In July, Crater 3 (SW crater) activity consisted mainly of degassing and sporadic ash emissions, with Strombolian explosions becoming more common in the second half of July.
Erosion of the N flank of Crater 1 by landslides in the upper Sciara del Fuoco increased in July, with the 30 December 2002 landslide scar extending backward and upslope, cutting the flank of the cone 50 m below the crater rim.
Geologic Background. Spectacular incandescent nighttime explosions at this volcano have long attracted visitors to the "Lighthouse of the Mediterranean." Stromboli, the NE-most of the Aeolian Islands, has lent its name to the frequent mild explosive activity that has characterized its eruptions throughout much of historical time. The small, 924-m-high 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 from about 13,000 to 5000 years ago was followed by formation of the modern Stromboli edifice. The active summit vents are located at the head of the Sciara del Fuoco, a prominent horseshoe-shaped scarp formed about 5000 years ago as a result of the most recent of a series of slope failures that extend 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, Piazza Roma 2, 95123 Catania, Italy (URL: http://www.ct.ingv.it/, Email: firstname.lastname@example.org).