M1.6 earthquake 16 km SSE of Saint George, Utah

A magnitude 1.6 earthquake struck 16 km SSE of Saint George, Utah on Sun, Dec 23, 2018, 5:23 AM MST (12:23 UTC), 9 km (6 mi) below the surface.

A larger quake followed: M3.8 14 km SW of Enterprise, Utah. This one was a foreshock.

Map

Where this earthquake was located, with the others nearby. Select one for its page.

Different scales measure different things and differ by a few tenths. The USGS marks one as preferred, and it is the one this page uses.

Mag.	Scale	Computed by	Notes
1.55	Md, duration	University of Utah Seismograph Stations	Preferred · Final · ±0.103 · 5 stations
1.6	ML, local (Richter)	Nevada Seismological Laboratory	Reviewed · ±0 · 1 stations

1 person reported to the USGS what they felt; the strongest reported shaking was II, weak shaking.

Reviewed by a seismologist.

Distance and direction from each place to the epicenter, with its forecast.

Within 100 km, magnitude 1.5 and up: 45 in the 60 days after this one and 9 in the 30 days before it.

From the USGS Earthquake Hazards Program and its partner networks, event uu60307977 (also filed as nn00671622). Read Thu, Oct 1, 2026, 9:58 PM UTC.