Terrawatch: the recipe for an explosive volcano eruption

Study reveals which conditions can render basaltic volcanoes highly destructive

More than half of the world's volcanoes are basaltic. Most basaltic eruptions tend to ooze their magma out in a relatively benign way, producing a thick, sticky flow. But occasionally they go off with a big bang, like the eruption of Mount Vesuvius in AD79, which destroyed the Roman town of Pompeii. Now a study reveals what makes some basaltic eruptions so explosive.

By cooking up miniature volcanoes in the lab, analysing rock samples flung from explosive basaltic eruptions and numerically modelling the eruption process, Dr Fabio Arzilli, from the University of Manchester, and colleagues showed that low temperature magma and fast ascent up the pipes are key conditions for an explosive basaltic eruption.