Why is the Icelandic Eruption so Violent?
Q: Basaltic volcanoes are not characteristically violent. Why is the current Icelandic eruption so violent?
From Anon (May 2010)
Reply by Dr Clive Oppenheimer
Although icelandic volcanism is predominantly basaltic, there are also eruptions of much more evolved magmas. Indeed, the recent eruptions of Eyjafjallajökull have erupted intermediate magma of about 58% silica. Add to that the interaction between magma and glacial meltwater in the crater and there is plenty of scope for vigorous explosive activity that produces dense eruptive columns rich in fine ash and steam.