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For Volcanologists Worldwide, a New Digital Home for All Things Volcano

Volcanologists now have their own online network: VHub.org, which promotes collaboration among volcano researchers and community partners by providing a place to share everything from eruption data to ash cloud simulations.
The website, created by the University at Buffalo's volcanology group, represents an innovative approach to facilitating partnerships around the world. Funding for the project comes from the National Science Foundation (NSF).
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How to watch world volcanoes on the web

During the past several weeks, many volcanoes have been active around the world. While we focus on our home volcano, it can be very interesting to check in with these other eruptions via the internet. The volcanoes getting the most attention now are El Hierro in the Canary Islands northwest of mainland Africa, Mount Etna on the Italian Island of Sicily, and Nyamuragira volcano in the Congo. You can keep up with world volcanism here
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Super-eruptions
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Scientists find possible trigger for volcanic super-eruptions

The "super-eruption" of a major volcanic system occurs about every 100,000 years and is considered one of the most catastrophic natural events on Earth, yet scientists have long been unsure about what triggers these violent explosions.
However, a new model presented this week by researchers at Oregon State University points to a combination of temperature influence and the geometrical configuration of the magma chamber as a potential cause for these super-eruptions.
Results of the research, which was funded by the National Science Foundation, were presented at the annual meeting of the Geological Society of America in Minneapolis, Minn.

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Three Active Volcanoes Spotted on Satellite Imagery from NASA

NASA keeps a watchful eye on volcanic activity around the world with many satellites. NASA has just released satellite images showing activity this week from volcanoes in the countries of Eritrea, Chile and Indonesia.
NASA's Terra satellite and the GOES-11 satellite captured ash plumes or heat coming from the Nabro volcano, the Puyehue-Cordón volcano, and the Soputan volcano, respectively, over the past week. There are a number of other volcanoes showing activity around the world, but thanks to good visibility these three volcanoes were more easily seen from space this week.

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Title: A rapid mechanism to remobilise and homogenise highly crystalline magma bodies
Authors: Alain Burgisser, George W. Bergantz,

The largest products of magmatic activity on Earth, the great bodies of granite and their corresponding large eruptions, have a dual nature: homogeneity at the large scale and spatial and temporal heterogeneity at the small scale. This duality calls for a mechanism that selectively removes the large-scale heterogeneities associated with the incremental assembly of these magmatic systems and yet occurs rapidly despite crystal-rich, viscous conditions seemingly resistant to mixing. Here we show that a simple dynamic template can unify a wide range of apparently contradictory observations from both large plutonic bodies and volcanic systems by a mechanism of rapid remobilisation (unzipping) of highly viscous crystal-rich mushes. We demonstrate that this remobilisation can lead to rapid overturn and produce the observed juxtaposition of magmatic materials with very disparate ages and complex chemical zoning. What distinguishes our model is the recognition that the process has two stages. Initially, a stiff mushy magma is reheated from below, producing a reduction in crystallinity that leads to the growth of a subjacent buoyant mobile layer. When the thickening mobile layer becomes sufficiently buoyant, it penetrates the overlying viscous mushy magma. This second stage rapidly exports homogenized material from the lower mobile layer to the top of the system, and leads to partial overturn within the viscous mush itself as an additional mechanism of mixing. Model outputs illustrate that unzipping can rapidly produce large amounts of mobile magma available for eruption. The agreement between calculated and observed unzipping rates for historical eruptions at Pinatubo and at Montserrat demonstrates the general applicability of the model. This mechanism furthers our understanding of both the formation of periodically homogenised plutons (crust building) and of ignimbrites by large eruptions.

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Oscillating "plug" of magma causes tremors that forecast volcanic eruptions: UBC research

University of British Columbia geophysicists are offering a new explanation for seismic tremors accompanying volcanic eruptions that could advance forecasting of explosive eruptions such as recent events at Mount Pinatubo in the Philippines, Chaiten Volcano in Chile, and Mount St. Helens in Washington State.
All explosive volcanic eruptions are preceded and accompanied by tremors that last from hours to weeks, and a remarkably consistent range of tremor frequencies has been observed by scientists before and during volcanic eruptions around the world.

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Volcanic Eruptions
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Learning from Volcanic Eruptions 200 Million Years Ago

Morgan Schaller, Jim Wright and Dennis Kent report that the level of atmospheric CO2 went from about 2,000 parts per million to 4,000 parts per million and then shrank back to pre-eruption levels over the next 300,000 years. This implies that events of this scale have the potential to rapidly double the concentration of CO2 in earth's atmosphere. Their work, funded by a grant from the National Science Foundation, was based on measurements on cores taken from sites in northeastern New Jersey. Schaller is a PhD student, Wright an associate professor and Kent a professor of earth and planetary sciences in Rutgers School of Arts and Sciences.
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Frozen blob of magma discovered in Nevada desert

New geologic mapping has discovered a 'frozen blob of magma in the desert ranges of northwest Nevada that may indicate the presence of a former volcano and provide more information about other similar granite intrusions in the area.
The ancient blobs were formed during the time of the dinosaurs (250 million years ago to about 65 million years ago). At that time, there was essentially one continuous subduction zone along western North America.
A subduction zone forms when one of Earth's tectonic plates is shoved underneath another one. The scraping of the two plates creates a seismically and volcanically active area around the subduction zone.
The ancient western North America subduction zone had an associated belt of volcanoes.

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Insight into volcanic eruptions, courtesy of space

Scientists are crediting satellite imagery with helping to predict where volcanic eruptions could strike. It is well known that earthquakes can stress Earth's crust and trigger subsequent quakes, but there has been no proof of this for volcanoes until now.
In September 2005, a volcanic event in Ethiopia's Afar Desert forced magma up through rocks in a crack, known as a dyke, resulting in a 60-km-long tear in Earths crust. Over the next four years, 12 more dykes were created in the same region near the Red Sea
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Just as thunder precedes lightning, earthquakes often foretell volcanic activity.
Before Iceland's Eyjafjallajökull volcano blew its top in April, spewing thick clouds of ash, the earth around it had already started rumbling, and geologists began warning about an impending eruption.

"It's very common for the two to be linked. Volcanic eruptions are usually preceded by earthquakes large and small" - Jonathan Snow, a volcanologist at the University of Houston.

In fact, Snow describes it as a "symbiotic" relationship.

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