Yellowstone National Park was struck by the biggest recorded earthquake in 34 years.
The 4.8 magnitude earthquake happened at 6.30am on Sunday morning near the Norris Geyser Basin and was felt in the Montana border towns of Gardiner and West Yellowstone, 20 miles from the epicentre.
No damages or injuries were reported.
The park's supervolcano however, was not affected by the earthquake.
Experts say it has the potential to erupt with a force about 2,000 times the size of the 1980 eruption of Mount St Helens in Skamania county, Washington and would devastate the United States and impact the rest of the world.
At least 25 earthquakes have been recorded at Yellowstone since Thursday. They are being linked to the continual upward movement of molten rock beneath the Earth's crust, according to the U.S. Geological Survey.
The national park covers an area of 3,472 miles including Wyoming, Montana and Idaho, and draws about 3 million visitors each year to its iconic geysers and wildlife.
It comes just two days after California was hit by a 5.1-magnitude earthquake which happened along the lesser known Puente Hills thrust fault stretching from the northern Orange County under downtown Los Angeles into Hollywood.
The US Geological Survey estimates that if a 7.5 magnitude quake struck along the Puente Hills fault it could kill 3,000 to 18,000 people and cause up to $250 billion (£151 billion) in damage.