YELLOWSTONE - 1,033 Yellowstone quakes recorded in one week. The Volcano Alert Level at Yellowstone National Park remained at “normal” Friday, despite a swarm of earthquakes large enough to trigger seismographs in the Flathead Valley and cause chatter on Twitter. Working around the clock, scientists with the U.S. Geological Survey’s Yellowstone Volcano Observatory had recorded more than 1,033 earthquakes since Monday, including at least eight events over magnitude three. That’s more than half the total annual average in the park, which is 1,600 a year.
... “This is a big swarm. These things don’t happen very often. They may have a deep volcanic connection, but right now, it seems to be related to tectonics.” There was a similar swarm in 2009. The swarm is on par with an event in 1985 in which scientist recorded more than 3,000 quakes. “It’s interesting, with swarms, the earthquakes can start up small. There’s no one big earthquake, there are just a bunch of smaller quakes that can increase in intensity and go back down.” Scientists have no way of knowing how long the swarm will last, though the one in 1985 went on for months.
...Prof. Robert B. Smith, a geophysicist at the University of Utah and one of the leading experts on earthquake and volcanic activity at Yellowstone, said that the activity is a "notable swarm."
...In late December 2008 and early January 2009, Yellowstone National Park experienced the second largest earthquake swarm in Yellowstone's recorded seismic history. The swarm under the north end of Yellowstone Lake consisted of 813 earthquakes with magnitudes ranging up to 3.9.
...Mike Stickney, director of earthquake studies at Montana Bureau of Mines and Geology, said there is no way to predict when the next big one will hit.