Yellowstone Sits Atop One of the World's Biggest, Active Volcanoes, One Capable of Laying Waste to Much of North America; Beginning in 2004, Volcanic Pressure Caused an Amazing Rise at the Park: the Park is in Constant Motion, the Land has Bulged, and the Ground is Sinking
Yellowstone National Park Is Moving
May 21, 2011ABC 4 News, Wyoming - The nation's oldest park is also one of the most studied. The interest is not just in it's amazing vistas and wildlife, but in the volcanic beast below the park.
Yellowstone sits atop one of the world's biggest, active volcanoes, one capable of laying waste to much of north America.
Scientists keep an eye on it using a network of seismic and GPS sensors.
Professor Emeritus Robert Smith of the University of Utah is one of those scientists. A geophysicist, Smith a leading expert on the Yellowstone super volcano.
"We monitor it in real time for earthquake swarms and ground deformation."He says the park is in constant motion. Visitors can't see it, but the ground at their feet is moving up and down as magma pushes against the thin crust and powers the park's many geysers.
The changes are most evident at the Norris Geyser Basin. Henry Heasler, the Yellowstone Park geologist said.
"It changes daily. Sometimes it's hard to keep up with the change near boardwalks because that impacts visitor and employee safety."And beginning in 2004, volcanic pressure caused an amazing rise at the park: three-inches a year for five-years.
"Why are all the hydrothermal features here?" Heasler continued, "The geysers? The mud pots? The steam vents? The hot springs? It's because of the heat beneath our feet."
Professor Smith said:
"That's a lot of uplift and it's over an area that's over the entire Yellowstone caldera -- 50-miles long of uplift."In fact, as the land has bulged, Yellowstone lake has tilted enough that its water has flooded out trees on the south arms.
"If you went under a rubber sheet," Heasler said describing the uplift, "And pushed your thumb up, it's not just sticking up where your thumb is, there's like a slope to it."
And now, the ground is sinking.
And the drop has brought up a whole new set of questions for scientists.
"Why haven't the trees emerged again?" asked Heasler. "We don't know."They are watching the data as well as the geothermal features of the park for clues.
At times, those geologists see themselves are doctors monitoring a patient. In this case, the patient took a deep breath (between 2004-09) and now it is letting it out. That much is clear from the observations.
The unanswered question is, "why?"
For more on the story, watch "Yellowstone Eruption" Friday night on ABC 4 News at 10:00 p.m.
Yellowstone Super Volcano is Even Bigger Than First Thought
May 21, 2011ABC 4 News - Planning a summer vacation? How about visiting one of the biggest, meanest, most active volcanoes on earth? It's right in our own backyard, just a five-hour drive north, at Yellowstone National Park. People come to the national park every year to see bear, elk and herds of bison, but most visitors never realize they're inside the mouth of a volcanic beast.
The mouth of the Yellowstone super volcano is big. The caldera -- the crater left by an eruption -- is roughly 14-hundred square miles. The southern half of the national park is swallowed by the caldera.
Super eruptions are the biggest blasts on earth, but fortunately, they're rare: a super eruption hasn't occurred in the recorded history of man.
Robert Smith, a professor emeritus of geophysics at the University of Utah and leading expert on the Yellowstone super volcano, has found enough clues to piece together a picture, using the results of three giant eruptions which occurred at 2-million, 1.2 million, and 640,000 years ago.
He said the first super eruption at Yellowstone was 2,500 times bigger than the 1980 eruption of Mount St. Helens. Ash from that eruption fell over much of the American West and Midwest, reaching all the way to the Gulf of Mexico. The ash that remained in the upper atmosphere circled the globe, plunging it into a volcanic winter that probably lasted years.
If such an eruption happened today, the explosion and pyroclastic flow (think a tsunami of superheated gas, rock and ash) would level the park and surrounding communities. A few inches of ash would fall on Salt Lake. No harvest would be possible in America's bread basket.
And of course, there would be that volcanic winter lasting years.
Using a new technique that makes images with electrical and magnetic fields in the earth, scientists at the University of Utah have been looking deep into the earth. Michael Zhdanov, professor of geophysics says with this technology,
"Now we can see through non-transparent media like rocks."The result? Scientists are seeing that the magma plume below Yellowstone is even bigger than first thought.
The technology has shown that the magma plume below Yellowstone is even bigger than first thought.
"Why are all the hydrothermal features here?" Heasler asked. "The geysers? The mud pots? The steam vents? The hot springs? It's because of the heat beneath our feet."Combined, there are more of those hydrothermal features in Yellowstone than any other place on earth.
In other words, you can thank the volcano for Old Faithful.
Although Internet prophets of doom are quick to predict a super eruption, scientists who know Yellowstone best believe a super eruption won't happen for another 100-thousand years … give or take a few thousand.
For more information on the Yellowstone Super Volcano, check out the following web sites:
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