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Six Russian volcanoes erupt
Volcanic activity increases around the Kamchatka peninsular as six volcanoes erupt simultaneously.

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Six Kamchatka Volcanoes Exhibit Activity Simultaneously For the First Time in Sixty Years
For the first time in sixty years six Kamchatka volcanoes exhibit activity simultaneously. They are Koryaksky, Shiveluch, Bezimyanny, Gorely, Karymsky volcanoes and Klyuchevskaya Sopka Volcano. All of them spout steam and gas almost simultaneously.

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For decades, geologists have been puzzled by the mechanisms that give rise to the kind of volcanoes that form the so-called "ring of fire" around the Pacific Ocean. These arc volcanoes, which account for about 10 to 25 percent of all volcanoes, are produced when one of the plates that make up Earth's crust plunges beneath another plate, a process called subduction.
What was unclear was what factors controlled when, how and at what depth fluids and molten rock from these subducting plates are released, giving rise to the molten magma in the Earth's mantle that would then come spewing to the surface in the form of a volcanic eruption. This process produces many of the world's major deposits of important metals, so understanding how it works could help in locating these sources.
The mystery has now been solved, thanks to fieldwork, experiments and computer modelling carried out by Professor of Geology Timothy Grove of the Department of Earth, Atmospheric and Planetary Sciences (EAPS), graduate student Christy Till, and three colleagues. The results were published in the June 4 issue of Nature.

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Volcanic eruptions
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New research on infrasound from volcanic eruptions shows an unexpected connection with jet engines. Researchers at Scripps Institution of Oceanography at UC San Diego speeded up the recorded sounds from two volcanoes and uncovered a noise very similar to typical jet engines.
These new research findings provide scientists with a more useful probe of the inner workings of volcanic eruptions. Infrasound is sound that is lower in frequency than 20 cycles per second, below the limit of human hearing.
The study led by Robin Matoza, a graduate student at Scripps Oceanography, will be published in an upcoming issue of the journal Geophysical Research Letters, a publication of the American Geophysical Union (AGU). Matoza measured infrasonic sound from Mount St. Helens in Washington State and Tungurahua volcano in Ecuador, both of which are highly active volcanoes close to large population centres.

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Volcanic Mesocyclone
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A 200-year-old report by a sea captain and a stunning photograph of the 2008 eruption of Mount Chaiten are helping scientists at the University of Illinois better understand strong volcanic plumes.
In a paper to appear in the March 26 issue of the journal Nature, the scientists show that the spontaneous formation of a "volcanic mesocyclone" - a cyclonically rotating columnar vortex - causes the volcanic plume to rotate about its axis. The rotation, in turn, triggers a sheath of lightning and creates waterspouts or dust devils. The origins of these volcanic phenomena were previously unexplained.

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Magma plumes
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Computer simulations, paleomagnetism and plate motion histories described in the journal Science reveal how hotspots, centers of erupting magma that sit atop columns of hot mantle that were once thought to remain firmly fixed in place, in fact move beneath Earth's crust.
Scientists believe mantle plumes are responsible for some of the Earth's most dramatic geological features, such as the Hawaiian islands and Yellowstone National Park. Some plumes may have shallow sources, but a few, such as the one beneath Hawaii, appear to be rooted in the deepest mantle, near Earth's core.
Such deep plumes have long been thought to be so immobile that the motions of continental and oceanic plates were measured against them, but University of Rochester geophysicist John Tarduno and his colleagues at Ludwig-Maximilians, Münster, and Stanford universities have combined magnetic evidence from the Pacific sea floor with computer modelling to show how the plume beneath Hawaii likely bent - its root barely moving while its top moved nearly 1,000 miles across the underside of the Pacific Ocean.

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Climate researchers have shown that big volcanic eruptions over the past 450 years have temporarily cooled weather in the tropics - but suggest that such effects may have been masked in the 20th century by rising global temperatures. Their paper, which shows that higher latitudes can be even more sensitive to volcanism, appears in the current issue of Nature Geoscience.
Scientists already agree that large eruptions have lowered temperatures at higher latitudes in recent centuries, because volcanic particles reflect sunlight back into space. For instance, 1816, the year following the massive Tambora eruption in Indonesia, became known as "The Year Without a Summer," after low temperatures caused crop failures in northern Europe and eastern North America. More extensive evidence comes in part from tree rings, which tend to grow thinner in years when temperatures go down.
This is one of the first such studies to show how the tropics have responded, said lead author Rosanne D'Arrigo, a scientist at the Tree Ring Lab at Columbia University's Lamont-Doherty Earth Observatory

Source The Earth Institute at Columbia University

Title: The impact of volcanic forcing on tropical temperatures during the past four centuries
Authors: Rosanne D'Arrigo, Rob Wilson & Alexander Tudhope

Palaeoclimate records have demonstrated links between high-latitude climate changes and tropical as well as high-latitude volcanic activity. However, little is known about the impact of high-or low-latitude volcanic eruptions on tropical climate, particularly for the period preceding the instrumental record. Here we use annually resolved temperature-related records from corals, tree rings and ice cores to investigate the relationship between volcanism and low-latitude climate. Over the past 450 years, we find an association between low-latitude volcanic events and lower sea surface temperatures in the tropical oceans. The longest sustained cold period in recent centuries occurred in the early nineteenth century, following the eruption of Tambora and a second, unidentified but presumably tropical, volcano. We therefore conclude that the tropical ocean-atmosphere system has been sensitive to changes in radiative forcing caused by tropical volcanism over the past several centuries.

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Superplumes
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Two giant plumes of hot rock deep within the earth are linked to the plate motions that shape the continents, researchers have found.
The two superplumes, one beneath Hawaii and the other beneath Africa, have likely existed for at least 200 million years, explained Wendy Panero, assistant professor of earth sciences at Ohio State University.
The giant plumes -- or "superpiles" as Panero calls them -- rise from the bottom of Earth's mantle, just above our planet's core. Each is larger than the continental United States. And each is surrounded by a wall of plates from Earth's crust that have sunk into the mantle.
She and her colleagues reported their findings at the American Geophysical Union meeting in San Francisco.
 
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RE: Volcanoes
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A Scots scientist who invented a new way to help predict when volcanoes will erupt has received a major award.
Dr Andrew McGonigle, from Edinburgh, uses a remote controlled helicopter which he flies over active volcanoes to gather his data.
He has been named a Laureate in the 2008 Rolex Awards for Enterprise, a prize which brings with it the funding to develop his idea further.

"What we are trying to do is develop a completely remote way of measuring carbon dioxide emissions from volcanoes. Carbon dioxide as a gas is very important with volcanology because it is released from rising batches of magma relatively early in the ascent process" - Dr Andrew McGonigle.

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Deep magma matters in volcanic eruption cycle
Although the Soufriere Hills volcano on Montserrat exhibits cycles of eruption and quiet, an international team of researchers found that magma is continuously supplied from deep in the crust but that a valve acts below a shallower magma chamber, releasing lava to the surface periodically.

"Continuous records of surface deformation are available for only a few volcanoes.  The Soufriere Hills volcano has been erupting since 1995 and provides a peek into the processes occurring deep beneath this stratovolcano" - Derek Elsworth, professor of energy and geo-environmental engineering, Penn State.

Stratovolcanoes are one of the most common forms of volcano on Earth. They are cone-shaped with steep sides created by episodic eruptions of magma that flow down from the cone a short way and create layer upon layer of volcanic material.

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