Dec. 4 (UPI) -- The traditional model of volcanic eruptions is wrong, according to new research.
Volcanoes aren't fueled by a large chamber of molten magma, scientists found -- they're fed by reservoirs of "mush." These so-called mush chambers are mostly filled with solid crystals. Magma is found in between the crystals.
The new findings could help scientists built more accurate models of a variety of volcanic phenomena.
"We now need to look again at how and why eruptions occur from mush reservoirs," Matthew Jackson, an earth scientist at Imperial College London, said in a news release. "We can apply our findings to understanding volcanic eruptions with implications for public safety and also to understand the formation of metal ore deposits associated with volcanic systems."
Recent surveys of volcanic chambers prove magma is mostly found in the spaces between solid crystals, not in a large vat. But volcanic eruptions spew large amounts of liquid molten rock, or magma.
The contradiction posed a problem: When volcanoes erupt, where does all the magma come from?
Jackson and his research partners were able to find a solution. New sophisticated models of mush reservoirs showed magma rises past the crystals because it is less dense. As it rises, the liquid rock melts some of the crystals, creating localized pockets of molten magma with few crystals.
The development of magma pockets within mush reservoirs can trigger eruptions, the new simulations showed.
"A major mystery about volcanoes is that they were thought to be underlain by large chambers of molten rock," said Stephen Sparks, an earth scientist at the University of Bristol. "Such magma chambers, however, were very difficult to find."
Sparks, Jackson and their colleagues shared the results of their latest research efforts this week in the journal Nature.
"The new idea developed by geologists at Imperial and Bristol is that molten rock forms within largely crystalline hot rocks, spending most of its time in little pores within the rock rather than in large magma chambers," Sparks said. "However, the rock melt is slowly squeezed out to form pools of melt, which can then erupt or form ephemeral magma chambers."