![]() ![]() “The two things we really saw were a fault valve that is controlling the episodic breakthrough of magma toward the surface, and second, we're able to follow the magma continuously and completely right to the lava lake,” Wannamaker said. This means molten rock flows directly from the mantle to the lava lake, although the magma goes through chemical changes as it ascends. The results show a straight, nearly vertical tube of magma below Erebus that is 20 kilometers wide and extends about 100 kilometers below Earth's surface. So, they can see what pathways magma takes from where it's created in Earth's mantle as it travels to the crust and eventually up to the surface. This allows them to differentiate between solid rock and molten rock (molten rock conducts electricity, whereas solid rock doesn't). Their method uses naturally occurring electromagnetic waves to image the rocks of Earth's crust and mantle based on how well they conduct electricity. Over the course of three Antarctic summer seasons, the researchers used magnetotelluric data acquired with helicopter support to visualize the rock structures below Ross Island, where Erebus is located. In 2014, Wannamaker, along with colleague Graham Hill and others, set out to map Erebus's plumbing using a different method. But this is difficult at Erebus because there haven't been enough earthquakes nearby to generate a good enough picture of its underbelly. Usually, they use seismic waves generated by earthquakes and other phenomena to create a kind of CT scan of the volcano's plumbing. Volcanologists often try to map the plumbing system below volcanoes to see what pathways molten rock takes to get to the surface. “It's one of the purest carbon dioxide-dominated volcanoes in the world.” “Erebus is an interesting volcano independent of it being in Antarctica,” Wannamaker said. It's also been active for over a million years and carries more carbon dioxide with its magma than many other volcanoes. It's an unusual volcano and a unique natural laboratory because of the football field-sized lava lake in its summit crater. Erebus and the conduit that brings hot magma to Earth's surface. “Understanding the controls and geometry of magma movements might also improve regional exploration models for rare elements that we need for everyday life.” Getting a peek behind the curtainĪ schematic of the plumbing beneath Mt. “Rift systems such as Mount Erebus have, in some geological intervals, emitted climate-forcing levels of carbon dioxide,” Wannamaker said. Studying Erebus's plumbing also helps geologists understand how rare chemical elements may make it from Earth's mantle to its surface, according to Phil Wannamaker, a geologist at the University of Utah and co-author of the study. ![]() The lava lake at Erebus is one of only a handful on Earth, so any insight into its workings helps scientists better understand how these unusual features form. ![]() This process helps keep the magma hot, dry and runny, which may explain why Erebus has small, gassy eruptions and how its lava lake has persisted for decades. The nozzle pushes small amounts of magma and carbon dioxide to the surface in pulses, rather than allowing them to flow continuously. The fault valve acts like a nozzle that controls the flow of magma and gas upward into Erebus's open lava lake. About 15 kilometers below the volcano, the tube narrows and turns slightly eastward, creating a structure geologists call a fault valve. The images show a nearly vertical tube of magma that extends about 100 kilometers down into the mantle. Scientists recently published the first three-dimensional schematics of Erebus's magma chamber, the conduit that brings melted rock from Earth's mantle up to the surface. Erebus, according to new research that illustrates the plumbing below Earth's southernmost active volcano for the first time. Antarctic Program will greatly miss his leadership, his research, and his humor.Ī 20-kilometer-wide tube of melted rock feeds the lava lake at Mt. Wannamaker was active in basic and applied geophysical research and the U.S. Wannamaker, quoted as part of this article, passed away in Salt Lake City, Utah. It is with great sadness we report that on Monday AugDr.
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