Report on Stromboli (Italy) — 15 July-21 July 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 15 July-21 July 2020
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2020. Report on Stromboli (Italy). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 15 July-21 July 2020. Smithsonian Institution and US Geological Survey.
38.789°N, 15.213°E; summit elev. 924 m
All times are local (unless otherwise noted)
INGV reported that during 13-19 July activity at Stromboli was characterized by ongoing explosive activity from two vents in Area N (north crater area) and four vents in Area C-S (south-central crater area). Explosions at the N1 vent in Area N sometimes ejected tephra 200 m high, and ejected lapilli and bombs radially. Low-intensity explosions at vent N2 ejected tephra 80 m high. Explosions at the S1 and S2 vents in Area C-S ejected tephra. A vent between S2 and C (Area C-S) was noted on 18 July and produced occasional explosions. A sequence of high-energy explosions began at 0500 on 19 July and ended at 0504. The first explosion originated at the central vent in Area C-S but within a few seconds involved all Area C-S vents. An ash plume rose as high as 1 km. Tephra was ejected radially; some material was deposited along the Sciara del Fuoco and reached the coast within about 40 seconds after the beginning of the event. Tephra fell in the towns of Liscione and Roccette. The event damaged the infrared camera at Pizzo (400 m elevation).
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 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 horseshoe-shaped scarp formed about 5,000 years ago due to 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.