A much stronger event was recorded on February 16, when a magnitude 3.1 tremor was felt 16 miles (25.7km) south of West Yellowstone.
The USGS said: “During February 2019, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, located 81 earthquakes in the Yellowstone National Park region.
“The largest event was a minor earthquake of magnitude 3.1 located 14 miles south of West Yellowstone, MT, on February 16 at 2.22pm MST.
“The earthquake was reported felt in Yellowstone National Park.
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