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).

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: M. Riuscetti, Univ di Udine.