Report on Stromboli (Italy) — 12 March-18 March 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 12 March-18 March 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Stromboli (Italy). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 12 March-18 March 2003. Smithsonian Institution and US Geological Survey.
38.789°N, 15.213°E; summit elev. 924 m
All times are local (unless otherwise noted)
INGV-CT reported that the eruption at Stromboli, which started on 28 December 2002, continued through 12 March. In early March two major lava flows spread NE and NW from the base of the NE crater. Hot aa lava blocks detached from lava-flow fronts causing several minor rockfalls and landslides along the Sciara del Fuoco. Lava entering the sea formed steam clouds. A decrease in lava-effusion rate from the 600-m-vent on 6 March led to a regression of the most advanced flow front to 300- to 400-m-elevation, and a smaller number of active ephemeral vents along the lava-flow field. Occasionally during 5-10 March, brown-to-pink ash emissions occurred at Crater 3 (the SW crater) that were probably produced from inner-crater collapses. No explosive activity has been observed at the summit craters since the start of the flank eruption. Detailed daily reports of volcanic activity (in Italian) are available at the INGV-CT website.
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 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 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.