Etna has had its ‘paroxysm’ #many. Every eruption is spectacular, but when they are so frequent it gets easier to focus on what is different with every eruption. Bruce Stout and Newby noted that the activity lasted much longer than previously in this series of paroxysms. Why this is, is off course a mystery, but maybe as time progresses we will find out if this is again some kind of new behaviour for Etna. For now, I don’t think many people mind that Etna keeps doing these things, since the eruptions are not much of a nuisance to the people living around it (at least, not more than usual with Etna’s eruptions), but are nice to watch for everyone.
Mr. Behncke of the INGV in Catania has written a nice summary / eyewitness report of the activity, which can be read on his Flickr-photostream. The question is indeed if this longer-lived activity can still be called a paroxysm.
Inge B. pointed to some images released by the INGV showing the Italian island of Vulcano, which seems to show a bit of unusually strong fumarolic activity.
The island is known to be volcanically active in recent history. The last eruption has been recorded in 1888 at the Fossa cone. The cone can be seen in the webcam image above. The Fossa cone has been the main center of activity in the last centuries, and fumarolic activity and gas emissions are ever-present to some degree at the Fossa cone. Sometimes, the activity peaks, like for example in 1985 and 1990, which shows that the town at the bottom of the Fossa cone is still under constant threat.
The island of Vulcano is off course most famous for being the place that gave volcanoes their name. In Greek and Roman mythology, the god Hephaestus, or Vulcan, was the god of fire and was thought to have its workshop below the Eolian island, leading to the frequent release of fire from the mountains on it. It is also the type locality for one of the 5 main types of magmatic eruptions; Vulcanian activity. This type of activity is characterized by viscous magma, andesitic to dacitic, that frequently erupts explosively and generates volcanic blocks and bombs that rain down on the surroundings. For comparison, Sakurajima is the best example of Vulcanian activity in recent years. The area where the volcanic blocks and bombs rained down during the 1888 eruption on Vulcano is where the town of Volcano Porto is now built, leading to the constant threat mentioned before if Vulcano decides to really wake up and go back to the behaviour the ancient Romans knew it for.
Meanwhile, Tolbachik seems to be re-thinking it’s decision that the eruption has now lasted long enough. Strong seismic activity has been recorded, together with strong gas-steam activity and a big thermal anomaly was seen on satellite images. Estimates of the erupted volume are well above 1 km3, so this number continues to rise for now.
Also, Granyia noted that the Chilean volcano Lascar had seen its alert level raised to Yellow, after reports of small explosions and some ash in steamclouds. Looking at the webcam, it looks like some glowing can be seen. Sernageomin reports (.pdf, in Spanish) that during a helicopter flyover, temperatures above 600 degrees celcius were measured in the crater using a thermal camera, which confirms the reports of glowing at night.
Post update by Spica:
The Sheepy Dalek bar is open and Alan sent in another Evil Riddle:
I shan’t beat about the bush – a real spiny subject this, but at least you wouldn’t need a tv aerial!
What am I?
What are my special properties?
Good luck and have fun!