A Swarm of Earthquakes Has Been Shaking Yellowstone’s Supervolcano
Geophysicists detected a swarm of more than 200 earthquakes around Yellowstone’s supervolcano within the past two weeks. Despite the alarming number, the scientists insist there’s nothing to be afraid of.
“This is what Yellowstone does; this is Yellowstone being Yellowstone,” Michael Poland, the scientist-in-charge of the USGS Yellowstone Volcano Observatory, told Live Science. “It experiences swarms all the time.”
Since February 8, Yellowstone has reported more than 200 earthquakes, with the largest hitting a 2.9 on the Richter Scale. All of the earthquakes were reported about five miles below the Earth’s surface.
Although the phrase “earthquake swarm” may seem apocalyptic, they’re a common occurrence at the national park. Scientists call multiple earthquakes “swarms” when they happen independently, without having been triggered by a main shock. Swarms account for more than half of all seismic activity at Yellowstone, but none have ever resulted in volcanic activity at the supervolcano caldera.
Last year, Yellowstone experienced an earthquake swarm that was 10 times more turbulent than this month’s activity. By September, a record-breaking 2,400 earthquakes were reported.
And although these quakes are happening perilously close to the supervolcano, it has remained dormant for centuries. The most recent eruption at Yellowstone happened more than 70,000 years ago, scientists say. The U.S. Geological Survey estimates a one in 730,000 chance of a massive volcanic explosion at Yellowstone, National Geographic reported. The USGS also said that the current seismic activity — despite its headline-grabbing number — is “relatively weak and actually represents an opportunity to learn more about Yellowstone.”