![]() Solar weather also produces waves that propagate through Earth.Ĭaptured by custom “voltmeters” on the surface and fed into a modeling algorithm, the waves can create a 3D picture of the electrical resistivity of material below, “kind of like a CT scan of the human body,” said Wannamaker. “A lightning bolt is an impulsive antenna, if you will, and electromagnetic waves ripple out from that into your survey area,” said Wannamaker. ![]() “Hats off to Graham for the energy and drive to cover the entire island,” said Wannamaker.Īt each site, they’d recorded the natural electromagnetic waves that travel through Earth from the Sun and distant lightning bolts. They visited 129 sites on Erebus and Ross Island, taking exhaustive measurements. So Hill, Wannamaker, and their colleagues took a different approach: magnetotelluric data.ĭuring summers between 20, the team visited Erebus via helicopter. But Erebus has very few crustal-scale earthquakes, hamstringing the method to shallow depths. Scientists use seismic waves traveling through Earth to ascertain the material below. Past studies into Erebus relied on seismic data to probe its inner workings. Although its name ultimately harkens to Greek mythology’s personification of darkness, Captain James Ross named the volcano after one of his ships, the HMS Erebus, in 1841. Mount Erebus overlooks McMurdo Station, and nearby sits the hut built by legendary polar explorer Ernest Shackleton and his men before they summited Erebus in 1908. The snow-covered Mount Erebus is the southernmost active volcano on Earth and shares Antarctica’s Ross Island with three other volcanoes, all dormant. Credit: Robert Falcon Scott/ Wikimedia, Public Domain “This is the first great image of one,” said geophysicist Phil Wannamaker at the University of Utah, who participated in the work.Įrebus has long been familiar to polar explorers-this photo was taken by Robert Falcon Scott on his ill-fated expedition to the South Pole. “If we can also get an idea of where the magmatic system is, you can better understand the monitoring data when these systems enter periods of unrest,” said lead scientist and geophysicist Graham Hill at the Institute of Geophysics at the Czech Academy of Sciences. This dryness allows magma to travel much closer to the surface than water (H 2O)-rich volcanoes that stall out at about 5 kilometers below the surface.ĬO 2-rich volcanic systems are less well understood than the more common H 2O-rich arc volcanoes. ![]() Instead, it’s rich in carbon dioxide (CO 2). Unlike arc volcanoes such as the Cascades in western North America, Erebus has very little water in its magma. Now, research has revealed the plumbing underneath Mount Erebus that keeps the lake full.ĭata taken by measuring natural electromagnetic waves traveling through Earth revealed the volcano’s magmatic system brings lava much closer to the surface than subduction arc volcanoes. The lake occasionally blasts out lava bombs from the summit crater of Mount Erebus, 3,794 meters high. critical for hazard assessment.One of Antarctica’s only active volcanoes is home to one of the few long-lasting lava lakes on Earth. C T I O N The persistent lava lake at Erebus volcano, Antarctica, provides an unparalleled opportunity. ![]() OF PETROLOGY VOLUME 54 Erebus volcano U-series isotopes HIMU Antarctica magma chamber residence. Crystal Growth Rates and Magma Degassing in the Erebus Volcano Magmatic System Using the 238U, 235U and. Journal of Petrology, 54 (2) 235-271 doi:10.1093/petrology/egs068Ĭrystal growth rates and magma degassing in the Erebus volcano magmatic system using measurements of. (2013) On the Time Scales of Magma Genesis, Melt Evolution, Crystal Growth Rates and Magma Degassing in the Erebus Volcano Magmatic System Using the 238U, 235U and 232Th Decay Series. Nearest other occurrences of Anorthoclase Ⓘ1 photo of Anorthoclase associated with Kenyte at this locality.Ĭlick here to view Mount Erebus, Ross Island, Ross Archipelago, Victoria Land, Eastern Antarctica, Antarctica Ⓘ1 photo of Anorthoclase associated with Phillipsite Subgroup at this locality. Ⓘ7 photos of Anorthoclase associated with Kenyaite at this locality.Ģ photos of Anorthoclase associated with Clinoenstatite at this locality.ġ photo of Anorthoclase associated with Aegirine at this locality. Good crystals or rich for species - important (!) Gray-green color and silky luster, but the crystals are often heavily included/covered by black glass. The bombs' glassy matrix quickly weathers away to leave deep piles of crystals up to 9 cm. When an explosion occurs, the crystals are caught in frothy phonolite bombs, which are tossed out along the crater rim.
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