A magnitude 3.6 earthquake struck Yellowstone National Park late Sunday, causing no injuries or damage, authorities said.
The University of Utah Seismograph Stations says the earthquake was followed by 13 aftershocks ranging up to 2.4 in magnitude.
The epicenter of the shock was a dozen miles northeast of West Yellowstone, Mont., and 4.2 miles deep. It was recorded at 8:29 p.m. Sunday.
Earthquakes in Yellowstone are fairly common, but seismologist say the 3.6-magnitude quake was a little stronger than usual. Quakes of magnitude 3.0 or larger have happened only 28 times in the greater Yellowstone park area in past 35 years.
Yellowstone is one of the most seismically active regions in the continental United States and absorbs hundreds of quakes occur each year.