Environment - Volcanoes may give a 100-year warning

 

Do volcanoes act as their very own early warning system? (Image: Michael Friedel/Rex Features)

A BLAST from the past has left tantalising hints that volcanic eruptions could be predicted decades in advance.

Volcanoes can signal their intent to erupt days or months ahead of time, giving authorities a chance to evacuate the area. Now evidence of the events leading up to a Bronze Age eruption suggests it might be possible to extend that warning period.

The Santorini volcano in the Greek islands lay dormant for 18,000 years before blowing its top some 3500 years ago, perhaps contributing to the demise of the Minoan civilisation. A close look at the pumices produced in the eruption shows that Santorini woke up around 100 years earlier.

Timothy Druitt of Blaise Pascal University in Clermont-Ferrand, France, and colleagues say that the crystals in the rocks have a structure and chemistry that only makes sense if they formed from magma that flooded into the magma chamber for a century before the eruption (Nature, DOI: 10.1038/nature10706).

In theory, seismic monitoring can spot signs that magma is gushing into the magma chambers of dormant volcanoes, including supervolcanoes like Yellowstone, warning of an eruption in the decades ahead.

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