Volcanic Magma On the Highway from Hell
The Costa Rican volcano Irazú drove the opposite direction of the classic AC/DC song by rocking out on the “highway from hell.” Thunderstruck scientists suggest understanding the seismic dirty deeds that shook Costa Rica all night long prior to Irazú’s rapid eruption, could lead to better predictions for other similar eruptions.
A study published today in the journal Nature found evidence that magma spewed by Irazú in the 1960s shot up from the bowels of the Earth in only a few months, as opposed to the centuries it takes for magma to reach the surface in many other volcanoes.
“There has to be a conduit from the mantle to the magma chamber,” said study co-author Terry Plank, a geochemist at Columbia University’s Lamont-Doherty Earth Observatory. “We like to call it the highway from hell.”
AC/DC references weren’t the only thing metal about the Irazú. Lava rock from the 1960s eruption contained the metal nickel. Magma in the Earth’s core holds trace amounts of nickel, but the metal usually diffuses out as the magma moves to the surface. The presence of nickel suggests the magma rose faster than the metal could escape.
Lava rock containing nickel also occurs in Mexico, Siberia and the Cascades of the U.S. Pacific Northwest.
“It’s clearly not a local phenomenon,” said Columbia University geochemist Susanne Straub in a press release.
Prior to even fast moving eruptions like Irazú, the Earth gives signs that calamity draws near. The cone at the top of the volcano bulges, gases escape through rock fissures and the temperature of the volcano rises. Earthquakes and other seismic activity also warn of an impending eruption.
Seismologists monitor these quakes and use them to give warnings that officials use to justify evacuating humans from volcanic danger zones. The new study in Nature helps scientists to set a speed limit for how fast magma can potentially rise.
“The study provides one more piece of evidence that it’s possible to get magma from the mantle to the surface in very short order,” said John Pallister, who heads the U.S. Geological Survey (USGS) Volcano Disaster Assistance Program in a press release. “It tells us there’s a potentially shorter time span we need to worry about.”
IMAGE: Irazú Volcano crater. (Daniel Vargas, Wikimedia Commons)