Though volcanic eruptions on the Galapagos Archipelago can appear menacing, they're typically slow moving and predictable. However, new research suggests even the most reliable volcanoes host the potential for violent surprises. Photo by Gabriel Salazar/La Pinta Yacht Expedition
July 29 (UPI) -- New research suggests a surprising diversity of magma types, including potentially explosive magma, can be found hiding within the pipes of seemingly reliable volcanoes.
Some volcanoes remain mostly quiet, until they don't, exploding violently -- decades of dormancy punctuated by deadly eruptions.
Other volcanoes, like those found in Iceland, Hawaii and the Galápagos Islands erupt more regularly. However, these reliable lava flows are slow moving. They can destroy houses, but their sluggish pace typically allows people plenty of time to get out of the way.
The volcanoes in the Galápagos have been producing the same long rivers of molten basaltic rock for millions of years, but new research suggests even the most reliable volcanoes can hide the potential for violent eruptions.
To better understand the types of magmas that flow through the underground pipes of Galápagos volcanoes, an international team of researchers analyzed the microscopic crystals found in the layers of ancient basaltic lava flows.
Their analysis -- published this week in the journal Nature Communications -- revealed the presence of a surprising diversity of magma types beneath the Galápagos volcanoes.
While the two volcanoes featured in the paper have consistently produced uniform basaltic lava flows at the surface, the latest research suggests their underground pipes also host magma similar in composition to the magma erupted by Mt. St. Helens.
Researchers estimate that because the volcanoes found in Iceland, Hawaii and the Galápagos Islands are so close to hot spots, the large flows of basaltic lavas flowing through the ground are great enough to drown out other types of magma.
However, the latest findings suggest that under certain geologic circumstances, more diverse -- and potentially explosive -- magma types could rise to the surface.
In other words, seemingly boring volcanoes contain the potential for more violent behavior.
"Although there's no sign that these Galápagos volcanoes will undergo a transition in eruption style anytime soon, our results show why other volcanoes might have changed their eruptive behavior in the past," lead study author Michael Stock said in a news release.
"The study will also help us to better understand the risks posed by volcanoes in other parts of the world -- just because they've always erupted a particular way in the past doesn't mean you can rely on them to continue doing the same thing indefinitely into the future," said Stock, a volcanologist at Trinity College Dublin.
Scientists have previously found ancient evidence of more violent eruptions among the Galápagos volcanoes, and now scientists know why.
"This discovery is a game-changer because it allows us to reconcile apparently divergent observations, such as the presence of explosive deposits at several Galápagos volcanoes," said co-author Benjamin Bernard, a volcanologist at the Geophysical Institute in Ecuador.
"It also allows us to better understand the behavior of these volcanoes, which is essential for volcano monitoring and hazard assessment," Bernard said.