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Etna volcano (Italy): new eruption with lava fountains from New South East crater on 5 Jan 2012 (paroxysm nr 19)Thursday Jan 05, 2012 17:59 PM | Age: 142 days
BY: TP  Webcam picture (Etna Trekking), captured by Mark Burns for Eruptions Blog.  Lava fountain at dawn during the 1st paroxysm of Etna volcano (photo courtesy: Francesco Pappalardo / www.flickr.com/photos/cicciofarmaco)  Heavy bombardment of glowing scoria and bombs on the fresh snow on the east flank of the New SE cone (photo courtesy: Marco Restivo / www.flickr.com/photos/marcorestivo/)  Lava fountains at dawn (photo courtesy: Marco Restivo / www.flickr.com/photos/marcorestivo/) Strombolian activity started late in the evening of 4 January, but was difficult to observe due to dense cloud cover. The activity increased slowly during the whole night, with more frequent and more powerful single explosions and ejected glowing bombs up to several 100 m height above the crater rim. At around 4 am , a lava flow started to emerge from the SE fissure cutting through the cone, announcing the slow start of the spectacular paroxysmal phase. Between 5h30 and 6 am, single strombolian explosions from the summit vent merged into continuous lava fountains up to about 600 m tall, and producing a large ash plume rising several kilometers. This phase was accompanied by the typical steep rise of the harmonic tremor signal as well recorded by INGV. Only the summit vent seems to have been active in this eruption. In contrast to previous paroxysms, the SE and N fissures did not produce lava fountains. Strong fountains lasted until 08h05 and the activity dropped sharly and ended at around 8h30. A very remarkable aspect of this eruption was the generation of small pyroclastic flows and lahars (mud flows). The heavy impacts of incandescent bombs on the snow-covered northern flank and base of the cone generated hydromagmatic steam explosions that turned into mud flows and turbulent mixtures of steam, ash and debris (pyroclastic flows). The latter reached the southern end of the fissure vents of the 2008-2009 eruption, ca. 1 km distance. This is a particular hazard to take into account during such and similar basaltic eruptions on snow-covered volcanoes. The lava flow produced several branches and took the same path as during the previous eruptions in late 2011, flowing down the steep slope east into the Valle del Bove until an elevation of about 2000 m. A small second lava flow emerged from a breach on the NW crater rim, but only reached the base of the cone.
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