Yellowstone National Park quivered early Sunday when the area's strongest earthquake in 34 years struck northwestern Wyoming, but no damage was reported.
The epicenter of the magnitude 4.8 quake, which occurred at 6:34 a.m., was four miles north-northeast of Norris Geyser Basin, according to University of Utah Seismograph Stations.
Seismic activity at Yellowstone isn't unusual, geologically speaking. The rugged land in the park, which boasts the world's largest collection of geysers, was formed by millions of years of volcanic activity.
Sunday's earthquake was the latest in a flurry of temblors that began Thursday, with more than 25 smaller quakes reported in that time by the University of Utah's seismographs.
The U.S. Geological Survey said that at first glance, there was no need for alarm, adding in a statement that there was "no indication of additional geologic activity other than continuing seismicity" after the main quake.
One of the survey's teams was already in the park and planned to visit the area near the epicenter to look for any surface changes or effects on the hydrothermal system at Norris Geyser Basin.