© Mark RalstonView of the Grand Prismatic hot spring in Yellowstone National Park
An ongoing earthquake swarm at Yellowstone volcano is now one of the biggest ever recorded, with over 2,300 tremors since it began in June.
As of August 30, 2,357 earthquakes had been recorded. The most powerful in recent weeks was magnitude 3.3; it took place on August 21.
The most powerful in the current swarm was a magnitude 4.4, which was recorded on June 15. Most of the earthquakes were in the magnitude 0 or 1 range, with a further 181 recorded at magnitude 2 and 11 at magnitude 3. Another 53 were less than 0, meaning they were very small events that could be detected only with sensitive earthquake-monitoring instruments.
Jamie Farrell, a research professor at the University of Utah, which is involved in monitoring seismic activity at Yellowstone, told
Newsweek that the swarm was "nothing out of the ordinary" and that it had "slowed down significantly but does occasionally have little bursts of activity that lasts for a few hours."
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