* Astronomy

If global warming, ocean acidification, and melting arctic ice werent enough to worry about, the Yellowstone supervolcano has risen at a record rate since mid-2004, likely because a Los Angeles-sized, pancake-shaped blob of molten rock was boiled up 6 miles beneath the slumbering giant, scientists funded by the National Science Foundation (NSF) report in the November 9 issue of the journal Science.

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Yellowstone National Park, once the site of a giant volcano, has begun swelling up, possibly because molten rock is accumulating beneath the surface.

"There is no evidence of an imminent volcanic eruption" - Robert B. Smith, a professor of geophysics at the University of Utah.

Many giant volcanic craters around the world go up and down over decades without erupting.
Smith and colleagues report in Friday's issue of the journal Science that the flow of the ancient Yellowstone crater has been moving upward almost 3 inches per year for the past three years.

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Searing ash rained from the skies, blanketing half the United States. The sun was erased behind dense black smoke and hot lava oozed across hundreds of miles of forests and fields.
It might have occurred more than 760,000 years ago, but the eruption of one of the countrys only supervolcanoes still has researchers and the public riveted.
Using a new technique developed at Rensselaer, a team of researchers has now determined that there was a massive injection of hot magma underneath the surface of what is now the Long Valley Caldera in California some time within 100 years of this gigantic volcanos eruption. The findings suggest that this introduction of hot melt led to the immense eruption that formed one of the worlds largest volcanic craters.

Read more  (Spring, 2007)

One of the largest supervolcanoes in the world lies beneath Yellowstone National Park and scientists say activity there is increasing.
Though the Yellowstone system, which spans parts of Wyoming, Montana and Idaho, is active and expected to eventually blow its top, scientists don’t think it will erupt any time soon. Supervolcanoes can sleep for centuries or millennia before producing incredibly massive eruptions that can drop ash across an entire continent.
Yet significant activity continues beneath the surface. And the activity has been increasing lately, scientists have discovered. In addition, the nearby Teton Range, in a total surprise, is getting shorter.

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Title: Crustal deformation of the Yellowstone–Snake River Plain volcano-tectonic system: Campaign and continuous GPS observations, 1987–2004
Authors: C. M. Puskas,  R. B. Smith, C. M. Meertens,  W. L. Chang

The Yellowstone–Snake River Plain tectonomagmatic province resulted from Late Tertiary volcanism in western North America, producing three large, caldera-forming eruptions at the Yellowstone Plateau in the last 2 Myr. To understand the kinematics and geodynamics of this volcanic system, the University of Utah conducted seven GPS campaigns at 140 sites between 1987 and 2003 and installed a network of 15 permanent stations. GPS deployments focused on the Yellowstone caldera, the Hebgen Lake and Teton faults, and the eastern Snake River Plain. The GPS data revealed periods of uplift and subsidence of the Yellowstone caldera at rates up to 15 mm/yr. From 1987 to 1995, the caldera subsided and contracted, implying volume loss. From 1995 to 2000, deformation shifted to inflation and extension northwest of the caldera. From 2000 to 2003, uplift continued to the northwest while caldera subsidence was renewed. The GPS observations also revealed extension across the Hebgen Lake fault and fault-normal contraction across the Teton fault. Deformation rates of the Yellowstone caldera and Hebgen Lake fault were converted to equivalent total moment rates, which exceeded historic seismic moment release and late Quaternary fault slip-derived moment release by an order of magnitude. The Yellowstone caldera deformation trends were superimposed on regional southwest extension of the Yellowstone Plateau at up to 4.3 ± 0.2 mm/yr, while the eastern Snake River Plain moved southwest as a slower rate at 2.1 ± 0.2 mm/yr. This southwest extension of the Yellowstone–Snake River Plain system merged into east-west extension of the Basin-Range province.

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