![]() ![]() "Basically, all the measurable properties of the lava are still up for grabs," Peters said. The gas cycling continues even when eruptions suddenly lower the lava lake level, he noted.Ĭomputer modeling of the upper and lower volcanic plumbing will help explain this strange set of behaviors and provide insight into the inner workings of other volcanoes, Peters said. "It looks like the two behaviors are very decoupled from each other," Peters said. The investigators think this difference means that the bomb-launching bubbles come from deeper in the volcano. Some of the volcano's lava bombs are nearly bus-size.Īt Erebus, these belches have a different composition than the gases that ebb and flow every 10 minutes, researchers discovered. Erebus erupts when a large gas bubble emerges and bursts in the lake, splattering lava on the surrounding slopes. (Image credit: Peter Rejcek, National Science Foundation.)īut just like a real body, this "breathing" comes from a different part of the volcano than its burping eruptions. "Batches of fresh magma come in as blobs, not as a continuous stream."Īntarctica is home to Mount Erebus, the southernmost active volcano on the planet and home to Earth's only long-lived lava lakes. "The physics of what's going on are fairly different, but it's an easy analogy," said Peters, who is co-author on the "lava lamp" study. Lava moves up and down the pipe - a flow and counterflow similar to a lava lamp, according to a model in a separate study to be published in the same issue of the journal Earth and Planetary Science Letters. Now put those blobs in an underground pipe that feeds the lava lake from a deeply buried magma chamber. Think of blobs rising and falling in a lava lamp. Here's what might cause the steady exhalations. "That's the $64,000 dollar question," Kyle said of the oddly predictable plumbing. ![]() With their bounty of data, the members of the Erebus team are now moving toward their next big goal: explaining how the volcano works. "The Peters paper represents a big step in understanding active lava lakes, in large part due to the uniquely detailed observations they have made of the lava lake activity," Patrick said. Geological Survey's Hawaii Volcano Observatory, who was not involved in the study. The long-term observations at Erebus volcano's lava lake are among the only rigorous studies of these valuable windows into magmatic systems, said Matt Patrick, a volcanologist with the U.S. Looming up from Ross Island, Erebus is visible from McMurdo research station and New Zealand's Scott Base. Both are steep-sided, cone-shaped phonolite volcanoes rising from rifts, where the Earth's crust is stretching apart. Though Erebus is the only active volcano with phonolite lava, its twin is Kilimanjaro in the East African Rift, Kyle said. (Image credit: Rich Esser/NMT)Įrebus volcano's magma is a rare type called phonolite, up to 100 times more viscous than the basalt at Kilauea in Hawaii and Erta Ale in Ethiopia. Įrebus is littered with anorthoclase feldspar phenocrysts that have weathered out of volcanic bombs. ![]() There are lakes at Erebus, Hawaii's Kilauea volcano, Ethiopia's Erta Ale volcano, and Nyiragongo volcano in the Democratic Republic of the Congo. Lava lakes are rare - there are only four long-lived lakes on Earth, because the volcano must continuously supply lava to the surface. It looks like a thick, treacly liquid, which is gradually convecting." "That's what we see in the velocity flow outward from the center of the lake. "Think of the lake as a bowl sitting on top of a pipe, and as fresh batches of magma come up into the bottom they rise up and spread out," Peters told Live Science's Our Amazing Planet. And lava cooling on the lake surface cracks and flows outward at a speed that matches the fluctuating gases. ![]() For instance, the lava heaves in concert with its 10-minute gas cycle, its surface rising and falling by about 6 to 10 feet (2 to 3 m), Peters said. The new study also reports other intriguing behavior in the bubbling lake. "The behavior has stayed remarkably constant, which is actually quite unusual for volcanoes," said Nial Peters, lead study author and a geophysicist at the University of Cambridge in the United Kingdom. Now, with year-round equipment, Erebus investigators have proved the cycle persists year-round, varying between five and 18 minutes since 2004, according to a study to be published June 2014 in the journal Earth and Planetary Science Letters. A thermal camera image of an eruption in Erebus volcano's lava lake. ![]()
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