Boris Behncke è un vulcanologo tedesco che lavora all’Ingv di Catania. Sull’Etna insieme ad altri appassionati fotografi, ieri mattina ha scattato delle meravigliose fotografie al 12° parossismo stagionale del vulcano. Pubblicate le foto su Flickr, Behncke ha allegato alle immagini un racconto davvero emozionante in lingua inglese, che vi vogliamo proporre integralmente.
.. and then the cone’s side burst open
As the 12th paroxysmal eruptive episode from Etna’s New Southeast Crater was in full swing, I was watching with a small group of other Etna aficionados from the excellent viewpoint on the Schiena dell’Asino, the south crest of the Valle del Bove about 5 km southeast of Etna’s summit. Intense lava fountaining from two vents within the crater was under way since about 10-15 minutes, and thus far, all seemed quite “smooth”, in my opinion – it was stunningly beautiful, especially because all this was happening at dawn, but it lacked the explosive drama of the previous paroxysm on 20 August.
I was alternatingly taking photographs and video clips, and after having shot a photograph at 06.19 h (local time = GMT +2), I switched to filming. About 35 seconds into the video clip, a massive explosion occurred at the base of the cone, as a new fracture had cut through its southeastern flank. I switched to photo mode again and took this image, roughly 20 seconds after the first outburst from the new fracture. Things had taken a spectacular and dramatic turn: a huge gash was slayed into the southeast flank of the new cone, and a cascade of lava rushed through this new breach, while lava fountains rose from numerous points along the fissure within the breach.
The 12th paroxysm of the New Southeast Crater was no longer a “smooth” affair. And, as I had announced in my 28 August 2011 evening post here on Flickr, the cone would look very different once we’d see it again after the end of the paroxysm, and after the clouds of gas, ash and dust would have cleared away.
A moment of dramatic change
One minute before, the latest paroxysm from the New Southeast Crater on Etna had been going on rather quietly – surely enough, there were two spectacular lava fountains many hundreds of meters high, but it was all kind of “clean”, or “smooth”, just very beautiful but nothing particular compared to the previous paroxysmal eruptive episodes from the same crater. Then, at 06.20 h (local time), the southeast flank of the cone that has grown in recent months around the New Southeast Crater, ruptured as a new eruptive fissure opened from the crater rim down to the base of the cone. A line of lava fountains sprang from a number of vents along this fissure, and the fountains that had been playing from vents within the crater immediately lost their splendor.
To us, a group of Etna lovers, photographers, and Alpine rescue service staff, plus myself, the show unfolding before our eyes was beautiful and breathtaking beyond description. Etna once more had invented one of her surprising twists, something we’re always certain to see without having the faintest idea what it will be.
The paroxysm lasted some 20 more minutes, then the vents within the crater stopped fountaining; by 06.50 h also the lowest of the newly-formed vent stopped fountaining, and there was some ash emission before all died down – and the cone reappeared from the ash, gas and dust clouds.
It had changed beyond recognition.
