A swarm of earthquakes is one sign that an eruption may be brewing and last winter Yellowstone National Park was rocked by a rash of tremors.
"There were over a thousand earthquakes in about one week. That isn't unprecedented in the parks history, but it is unusual" - Park Geologist Hank Heasler.
"It was one of the largest swarms in the past 20 years. It certainly got a lot of people's attention, including ours" - USGS Volcanologist Dr. Jake Lowenstern.
Hundreds of small earthquakes at Yellowstone National Park in recent weeks have been an unsettling reminder for some people that underneath the park's famous geysers and majestic scenery lurks one of the world's biggest volcanoes. In the ancient past, the volcano has erupted 1,000 times more powerfully than the 1980 blast at Mount St. Helens, hurling ash as far away as Louisiana. No eruption that big has occurred while humans have walked the earth, however, and geologists say even a minor lava flow is extremely unlikely any time soon. Some observers are nonetheless warning of imminent catastrophe.
A few little earthquakes here or there is just a part of everyday life when you live on top of the largest supervolcano in North America. But in the past eight days, there have been more than 400 earthquakes at Yellowstone National Park - where the volcanic system powers the geysers, mud pots and steam vents.
Yellowstone Lake Earthquake Swarm Update: 2 January 2008
The University of Utah Seismograph Stations reports that as of 1800 MST on 2 January 2009, seismicity of the ongoing Yellowstone earthquake swarm continues. Over 500 earthquakes, as large as M 3.9, have been recorded by an automated earthquake system since the inception of this unusual earthquake sequence that began Dec. 27, 2008. More than 300 of these events have been reviewed and evaluated by seismic analysts. Depths of the earthquakes range from ~ 1km to around 10 km. We note that the earthquakes extend northward from central Yellowstone Lake for ~10 km toward the Fishing Bridge area, with a migration of recent earthquakes toward the north. Some of the dozen M3+ earthquakes were felt in the Lake, Grant Village and Old Faithful areas.
Any disaster fiend will tell you that Yellowstone National Park is long overdue for a monster eruption that could leave as much as half the U.S. under a blanket of ash. And there are rumblings the big one could be imminent in the wake of a series of 30-plus mini-earthquakes in the park over the past few days--too weak to be felt by humans for the most part but picked up by the seismometers at the University of Utah.
Earthquake Swarm Strikes Yellowstone Ranging in size from magnitude 2.1 to 3.8, over 20 quakes have hit the Yellowstone region in the past 2 days. These quakes are occurring beneath Yellowstone Lake.
Yellowstone National Park was jostled by a host of small earthquakes for a third straight day Monday, and scientists watched closely to see whether the more than 250 tremors were a sign of something bigger to come. Swarms of small earthquakes happen frequently in Yellowstone, but it's very unusual for so many earthquakes to happen over several days.
The geysers of Yellowstone National Park owe their existence to the "Yellowstone hotspot"--a region of molten rock buried deep beneath Yellowstone, geologists have found. But how hot is this "hotspot," and what's causing it? In an effort to find out, Derek Schutt of Colorado State University and Ken Dueker of the University of Wyoming took the hotspot's temperature. The scientists published results of their research, funded by the National Science Foundation (NSF)'s division of earth sciences, in the August, 2008, issue of the journal Geology.
When wildfires raged through more than a million acres of a beloved national park, the destruction seemed complete. But a UW researcher looked closer and found hope growing among the remains.