2020 Magna Earthquake

Utah experienced a magnitude 5.7 earthquake
on March 18, 2020 at 7:09 a.m.

On the morning of Wednesday, March 18, 2020, northern Utah experienced a magnitude (M) 5.7 earthquake with an epicenter north of Magna, Utah. More than 2,400 aftershocks have occurred since the initial M5.7 earthquake. Additional aftershocks are expected to occur but with decreasing frequency over time. Utah experienced occasional spikes of felt aftershocks of M4 or M3 for weeks afterward.

The count includes:
6 in the magnitude 4 range
34 in the magnitude 3 range
148 in the magnitude 2 range.

Summary on USGS Website

U of U Seismograph Stations Data

Main Quake ShakeMap and Aftershock Timeline

UUSS ShakeMap

Magnitude vs Time

Preliminary Models and Information

This conceptual model illustrates one possible scenario for the location of the M5.7 Magna earthquake and its aftershocks relative to the Wasatch fault and associated faults. The M5.7 earthquake and some of its aftershocks might be on the Wasatch fault or on another nearby fault in the network of faults known as the Wasatch fault system. It is difficult to know for certain which fault or faults these earthquakes occurred on because the locations of these faults at depth are poorly known.

View the U of U Seismograph Stations Website

Example

New Publication from the UUSS

Seismic Analysis of the 2020 Magna, Utah, Earthquake Sequence: Evidence for a Listric Wasatch Fault

Published September 10, 2020


View the Full Publication

Geology of the Magna Earthquake

The magnitude 5.7 earthquake and subsequent aftershocks occurred in bedrock. Valley deposits of clay, silt, sand, and gravel in the area are between 200 and 1000 feet thick. The earthquake and aftershocks occurred at depths of about 1 to 8 miles. During the earthquake, the bedrock slid past itself along a crack called a fault. Before the earthquake, friction along the fault kept the bedrock from moving. Then, when stresses in the rock finally built up to overcome the frictional resistance on the fault, the bedrock moved and the stress was released, causing the earthquake. With each break (or rupture) of a fault, the rocks around the earthquake adjust and move in the same fashion; this period of adjustment is shown by the grouping of aftershocks. Analysis is ongoing but there has not been a determination of which fault zone the Magna earthquake occurred on.

Epicenter Map

Epicenter map of earthquakes from the Magna Earthquake Sequence.

U of U Seismograph Stations

3D Model

2020 M5.7 Magna, Utah Earthquake Locations
Updated: July 14, 2020 with 2,317 events

Visit 3D Model of Magna Earthquake

Utah Geological Survey

Utah Geological Survey – Information on the March 18, 2020, Magna Earthquake

Visit the Utah Geological Survey Website

New Publication from the UGS

Geologic Setting, Ground Effects, and Proposed Structural Model for the 18 March 2020 Mw 5.7 Magna, Utah, Earthquake

Published December 30, 2020


View the Full Publication

Frequently Asked Questions

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Media

  • Magna Damage in downtown Magna from the Magna Earthquake 2020
  • Magna Roof and shingles damaged from the Magna Earthquake 2020
  • Magna Damage to brick wall in Salt Lake City from the Magna Earthquake 2020
  • Magna Lateral spread geologic features near the Jordan River
  • Magna Damage in downtown Magna from the Magna Earthquake 2020
  • Magna Video of ground shaking from the Magna Earthquake 2020