A magnitude 3.8 earthquake near Mammoth, Park County, Wyoming, USA, was reported only 6 minutes ago by the United States Geological Survey, considered the key international and national agency that monitors seismic activity in the US. The earthquake occurred at a very shallow depth of 0.5 miles beneath the epicenter in the morning on Tuesday, August 19th, 2025, at 11:14 am local time. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.A second report was later issued by The Incorporated Research Institutions for Seismology (IRIS), which listed it as a magnitude 3.8 earthquake as well. A third agency, the European-Mediterranean Seismological Centre (EMSC), reported the same quake at magnitude 3.9.Based on the preliminary seismic data, the quake should not have caused any significant damage, but was probably felt by many people as light vibration in the area of the epicenter. Weak shaking might have been felt in Mammoth (pop. 260) located 13 miles from the epicenter.Other towns or cities near the epicenter where the quake might have been felt as very weak shaking include West Yellowstone (pop. 1,300) located 16 miles from the epicenter, Gardiner (pop. 880) 17 miles away, and Big Sky (pop. 2,300) 41 miles away.Earthquake data: Date & time: Aug 19, 2025 10:14 am (Denver time) local time (19 Aug 2025 17:14 GMT)Magnitude: 3.8Depth: 0.81 kmEpicenter latitude / longitude: 44.82°N / 110.86°W (Park County, Wyoming, United States)Primary data source: USGS