Report on Stromboli (Italy) — December 1990
Bulletin of the Global Volcanism Network, vol. 15, no. 12 (December 1990)
Managing Editor: Lindsay McClelland.
Stromboli (Italy) Activity drops to occasional explosions; seismicity declines
Please cite this report as:
Global Volcanism Program, 1990. Report on Stromboli (Italy). In: McClelland, L (ed.), Bulletin of the Global Volcanism Network, 15:12. Smithsonian Institution. http://dx.doi.org/10.5479/si.GVP.BGVN199012-211040.
38.789°N, 15.213°E; summit elev. 924 m
All times are local (unless otherwise noted)
Strombolian activity, abnormally vigorous during early October, began to decline in late October, and reached "normal" levels by the end of November. On 23 November, weak fumarolic activity was observed on the W rim of Crater 3, and continuous rumbling punctuated by rare explosions were reported from vent 3 in Crater 1. No activity was observed in Crater 2. The average tremor amplitude and the number of major shocks decreased to levels lower than in June when the paroxysmal phase began (figure 9).
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: M. Riuscetti, Univ di Udine.