Report on Stromboli (Italy) — 28 August-3 September 2019
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 28 August-3 September 2019
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2019. Report on Stromboli (Italy). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 28 August-3 September 2019. 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 the paroxysmal eruption at Stromboli recorded at 1217 on 28 August produced an ash plume that rose 4 km above the summit. The eruption consisted of three explosions; the first two occurred at the Area C-S (South Central crater area), and the less intense third event occurred at Area N (north crater area) and ejected material onto the Sciara del Fuoco. Material from the collapse of the eruption plume contributed to the generation of a pyroclastic flow that traveled down the Sciara del Fuoco and several hundred meters out to sea. Morphological changes to Area N were evident after the paroxysm. The complex of small scoria cones, which had grown around the vents during the last few weeks, were destroyed. The NW crater rim of Area N had subsided, allowing lava flows to travel down the Sciara del Fuoco. During an overflight on 30 August volcanologists noted that Area N had collapsed and contained three vents generating Strombolian activity, and Area C-S had one large crater exhibiting Strombolian activity.
Strombolian activity resumed after the paroxysm on 28 August; lava flows from Area N reached the coastline by 1945. The next day lava from Area N flowed halfway down the Sciara del Fuoco at 2123 on 29 August and shed material from the front that rolled down to the coast. A new explosive sequence at Area C-S began at 2243 and produced tephra fall in Ginostra (1.5 km from the summit). A low-intensity explosion was recorded at 2329. A lava flow from Area C-S reached the sea during the early part of 30 August. Strombolian activity persisted at moderate levels during 31 August-3 September.
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.