Report on Etna (Italy) — 5 October-11 October 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
5 October-11 October 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Etna (Italy). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 5 October-11 October 2016. Smithsonian Institution and US Geological Survey.
37.748°N, 14.999°E; summit elev. 3320 m
All times are local (unless otherwise noted)
On 10 October INGV reported that during the past few weeks high-temperature degassing had continued from a vent that had opened on 7 August in the E portion of Etna's Voragine crater. In addition minor and infrequent ash emissions from old pulverized rock rose from a vent located on the upper E flank of the New Southeast Crater cone. In the early afternoon of 10 October an explosion occurred at the Bocca Nuova crater, in an area between the crater and the nearby Voragine crater. The explosion was recorded at 1526, and produced a distinct thermal anomaly and an ash puff that rose a few hundred meters. During the next few hours similar seismic events were detected although weather cloud cover prevented visual observations.
Geological Summary. 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.