Magnitude 3.3 near Park City, UT


University of Utah Seismograph Stations

Released: September 18, 2017 12:00 PM MDT

The University of Utah Seismograph Stations reports that a minor earthquake of magnitude 3.3 occurred at 11:21 AM on September 18, 2017 (MDT). The shock was located 14 km (8 miles) beneath the Wasatch Mountains, 5 km (3 miles) south of the town of Summit Park, Utah, and 11 km ( 7 mi) WNW of Park City, UT. This earthquake was reported felt in Park City and Salt Lake City, Utah, other locations in the Salt Lake Valley, and in northern Utah County. Four other earthquakes of magnitude 3.0 or greater have occurred within 25 km (16 miles) of the epicenter of this event since 1962. The largest of these events was a magnitude 3.6 on June 30, 1999, 6.9km ( 4.3 mi) W of Park City, UT.

Anyone who felt the earthquake is encouraged to fill out a survey form either on the Seismograph Stations website: or the US Geological Survey website:


Earthquake Summary:

Date (UTC): September 18, 2017 Time (UTC): 17:21

Date (local): September 18, 2017 Time (local): 11:21 AM MDT

Latitude: 40 42.05′ N

Longitude: 111 36.55′ W

Depth: 11.0 km below sea level
13.6 km below the surface

Preferred magnitude: 3.30 Ml