Report on Etna (Italy) — 30 May-5 June 2001
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 May-5 June 2001
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2001. Report on Etna (Italy). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 30 May-5 June 2001. Smithsonian Institution and US Geological Survey.
37.748°N, 14.999°E; summit elev. 3295 m
All times are local (unless otherwise noted)
According to the Italy's Volcanoes website, volcanic activity was at similar levels as it has been during the previous few weeks. Lava continued to travel from a vent on the NNE flank of the Southeast Crater cone, and mild, discontinuous Strombolian activity continued at the Southeast Crater's summit vent. Scientists determined that the lava effusion rate was approximately 5-10 cubic meters per second, which is high for Etna. On 31 May mountain guides reported that pressure waves, which were caused by explosions, were observed approximately every 10 minutes and that volcanic bombs were thrown ~100 m above the crater rim. Degassing was observed at Southeast Crater and occurred to a lesser extent at Bocca Nuova crater, but increased at Northeast Crater.
Geologic Background. Mount Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BCE. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km horseshoe-shaped caldera open to the east. Two styles of eruptive activity typically occur, sometimes simultaneously. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more summit craters. Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by Strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.
Source: Italy's Volcanoes