In what is sounding like a bit of a broken record, the eruption at Eyjafjallajökull is still going. However, we might be beginning to see some changes in the style of volcanism - even the first suggestion of lava flows at the new crater. As mentioned yesterday, since the eruption became subglacial, we've been seeing eruptions where water - in this case glacial meltwater - has been playing a very important role, creating phreatoplinian or surtseyan style eruptions driven by steam explosions. Although the ash is andesitic, most of the explosiveness of the eruption likely lies with the water. The ash plume at the volcano this morning is smaller than 3,000 meters / 10,000 feet and after watching some of the show that Eyjafjallajökull put on last night, I would venture to say that much of the activity (Icelandic) is strombolian, with explosions (some large) of lava at the vent, throwing incandescent ash and bombs. The explosions are coming from gases escaping from the magma in the conduit and these bombs can travel hundreds of meters - but it is less likely to produce the large ash plumes we have been seeing. All of this implies to me that right now, there is less meltwater entering the crater area. This could change quickly, but this eruption has become a little more like Ruapehu in 1995-96 with abundant small explosions and ash plumes as the andesite erupts.
fuente El vulcanólogo Olgeir Sigmarsson
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