Report on Etna (Italy) — 25 January-31 January 2012
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 25 January-31 January 2012
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2012. Report on Etna (Italy) (Sennert, S, ed.). Weekly Volcanic Activity Report, 25 January-31 January 2012. Smithsonian Institution and US Geological Survey.
Etna
Italy
37.748°N, 14.999°E; summit elev. 3357 m
All times are local (unless otherwise noted)
Sezione di Catania - Osservatorio Etneo reported that an explosion at the New Southeast Crater (New SEC) of Etna generated an ash plume at that rose 400 m above the crater at 1906 on 27 January. An explosive ash emission at 1124 from the vent on the W portion of the crater floor was followed by others that were less intense. At 2140 an explosion ejected incandescent material in a narrow vertical jet that rose a few tens of meters above the crater. A small Strombolian explosion occurred at 2231. On 28 January sporadic ash emissions continued from New SEC.
Geological Summary. Mount Etna, towering above Catania on the island of Sicily, has one of the world's longest documented records of 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 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.