M 3.6 in Yellowstone National Park


University of Utah Seismograph Stations
Released: July 16, 2021 08:15 PM MDT

The University of Utah Seismograph Stations reports that a minor earthquake of magnitude 3.6 occurred at 06:45 PM on July 16, 2021(MDT). The epicenter of the shock was located beneath Yellowstone Lake, 7.4 mi SSE of Fishing Bridge, WY.  This earthquake is part of an intense sequence of small earthquakes, known as a swarm, that began yesterday afternoon (July 15).  There have been approximately 200 earthquakes in this swarm so far, including three others of magnitude 3.0 or larger and approximately 40 in the magnitude range 2 to 3.  Earthquake swarms are common in the Yellowstone National Park region, and account for roughly half of the total seismicity in the Yellowstone region.  The current swarm is occurring in an area that has had swarm activity in the recent past, including the 2008-2009 Yellowstone Lake swarm that included over 800 earthquakes.

Anyone who felt the earthquake is encouraged to fill out a survey formon the US Geological Survey website: earthquake.usgs.gov.

Earthquake Summary:
Date (UTC): July 17, 2021      Time (UTC): 00:45
Date (local): July 16, 2021     Time (local): 06:45 PM MDT
Latitude: 44 27.64′ N
Longitude: 110 20.83′ W
Preferred magnitude: 3.6 Ml