Since the magnitude 5.7 Magna earthquake two weeks ago we have received many earthquake-related questions and requests for more information.

We have teamed up with the Division of Emergency Management (DEM) and University of Utah Seismograph Stations (UUSS), among others, to launch a new website at earthquakes.utah.gov.

Magnitude 6.5 Earthquake Shakes Central Idaho

What does it mean for Utah? Learn more at earthquakes.utah.gov.

Magnitude 5.7 Earthquake Hits Utah

On the morning of Wednesday, March 18, 2020, northern Utah experienced a magnitude (M) 5.7 earthquake with an epicenter north of Magna, Utah. Multiple aftershocks have occurred since the initial M 5.7 earthquake. Additional aftershocks are expected to occur but with decreasing frequency over time.

Field teams of geologists from the Utah Geological Survey mobilized to look for evidence of surface fault rupture, liquefaction, lateral spread, and other geological effects from the earthquake.

Current information about the earthquake can be accessed through the digital clearinghouse web page:

Generalized cross section shoing a fault rupture which causes an earthquake and generates seismic waves.

Generalized cross section showing a fault rupture which causes an earthquake and generates seismic waves.

For additional information on the March 18 Magna earthquake, and how you can be prepared for future earthquakes, see the following information sources:

UUSS Press Conference on 5.7 Magnitude Earthquake
3D Model of Earthquake Locations

Was the March 18, 2020, Magna Earthquake in the Forecast?

In 2016, the Working Group on Utah Earthquake Probabilities (WGUEP) published a 50-year forecast for moderate to large earthquakes in the Wasatch Front region. They determined there was a 93% chance of having one or more earthquakes of magnitude 5 or larger in that time period. Given that high probability, the March 18, 2020, magnitude 5.7 Magna earthquake was an expected earthquake.

It’s important to understand that the Magna earthquake was not “The Big One” that Utah residents hear about from time to time. The Wasatch Front area has the potential to experience an earthquake larger than magnitude 7, up to a maximum of about magnitude 7.6, which would result in far greater and wide-ranging damage, injuries, and likely deaths. In their 50-year forecast, the WGUEP determined there is a 43% probability, or about a 1-in-2 chance, of having one or more earthquakes of magnitude 6.75 or greater in that time period.

The Magna earthquake should be a reminder that Utahns live in earthquake country, and that there is a reasonable chance that people living in Utah today could experience a large earthquake in their lifetime. As a society, we shouldn’t fear the future, but we should prepare for it.

The WGUEP full scientific report can be accessed here.

A non-technical fact sheet summarizing the WGUEP can be accessed here.

Magna Earthquake Digital Clearinghouse

The UGS Geologic Hazards Program has put together a digital clearinghouse of photos and resources from the Magna M5.7 Earthquake. These items are available to anyone and can be freely distributed.  More items will be added as our field teams continue to investigate the recent earthquakes.