There has been an update on the volcano's activity, which has increased significantly, although still nobody knows if or when it might erupt. Here's
the link (in greek) :
And here's the rough google translation:
The Vault of magma (molten rock in) beneath the volcano has expanded significantly, by about 10 to 20 million cubic meters between January 2011 and
April 2012, according to British scientists of the universities of Oxford and Bristol, in collaboration with Greek colleagues from the University of
Athens (Department of Geology & Paleontology) and the National Technical University (Higher Geodesy Laboratory).
Scientists estimate that the "inflation" of the magma has a volume of up to 15 times larger than the Olympic Stadium in London. Adding this magma in
terms of volume, is the most important that has taken place since 1955, shortly after the last eruption.
Researchers led by Professor David Pyle Volcanology Volcanology and Michelle Parks of Oxford Department of Geosciences, and Juliet Biggs of Bristol
Department of Geosciences, made after publication in the journal "Nature Geoscience", estimated that the rise of magma led in elevation of the
surface of the island 8 to 14 cm at the same time. The calculations were spot on Santorini made with the help of satellite radar images provided by
the European Space Agency (ESA) and the German Space Agency (DLR), and GPS measurements from the ground.
Although new data shed more light on the function of the volcano (which was around 1600 BC, scored one of the largest eruptions in history, possibly
leading to the destruction of the Minoan civilization), according to the researchers, it shed light on the major question: when the volcano will erupt
The "reviving" the volcano was recorded at the beginning of 2011, small earthquakes, which attracted the attention of Greek and foreign scientists,
and for about 25 years there was relative quiet in the caldera. The micro-earthquakes were accompanied by some other circumstantial evidence, such as
changes in the color of water in some places and greenhouse gas with a characteristic odor.
The researchers estimate that the amount of molten rock (magma) that has accumulated beneath the volcano last year, equivalent to about 10 to 20 years
of development of the volcano. They note, however, that this does not mean that any imminent eruption, however, such as stress, seismic activity has
clearly moderated in recent months.
The researchers noted that the volcano has two different kinds of eruptions over time: first small explosions that occur relatively frequently and
emit lava, and big explosions rarely occur at about 10,000 to 30,000 years. Both types explosions considered that "hatch" a shallow chamber magma
which is fed continuously by small quantities of molten rock, which rise from the bottom up.
However, as the new study, geological (mineralogical) studies show that at least 15% of the material ejected during the Minoan eruption, reached the
magma chamber less than 100 years before the explosion, ie not gradually over time but in much shorter time.
According to the researchers, whether the volcano is the most common (slow) phase accumulation of lava, or in rarer (and fast) explosive phase, the
shallow magma chamber fed occasionally with rapid magma flow quantities. The duration of such periods of magma supply is short in relation to the
intermediate resting periods, while when these occur occasional feedbacks, ie their timing, dependent on the ground dynamics of even deeper portion of
the magma below the Santorini.
During the most recent eruptions of the volcano, have risen to the surface are usually two different types of magma, mainly dacite (lava rich in
silica) and secondarily andesite (hottest lava with less silica). Previous studies have shown that the bursts appear to be triggered by rising to the
surface of andesite, who "stir up" the most abundant dacite, thus triggering the explosion, probably within a few weeks.
But since, according to the British geoscientists (whose research contributed Greek researchers Legal Friday, Xanthos Papanikolaou, Dimitris paradise,
Vangelis and Costas Raptakis sugar), recent volcanic activity has gone on much longer, it is assumed that the molten rock Now that accumulate beneath
Santorini is dacites and andesites not.