Researchers report Yellowstone earthquake swarm

Yellowstone National Park, Wyo. – Add another small earthquake to the swarm of temblors that have rattled Yellowstone National Park in recent days. The U.S. Geological Survey says a 3.3-magnitude earthquake struck at 8:39 p.m. Monday, and it was centered 9 miles southeast of the town of West Yellowstone, Mont. No damages or injuries have been reported.

Rafael Abreu, a USGS geophysicist, says a swarm of earthquakes has hit the park in recent days, which is normal.

Jamie Farrell, a doctoral student at the University of Utah, says the swarms generally last from a few days to weeks but sometimes last for months. The recent series of quakes started Sunday night, and Farrell says more than 200 had been counted by 9 a.m. Monday.

On Monday night, the USGS says, one person within the park had reported feeling the 3.3-magnitude quake.