March 18, 2020 Earthquake: Utah, United States

Ref #13456:

Many buildings damaged in the Salt Lake City area, including the Salt Lake City International Airport and Salt Lake Temple, and widespread power outages occurred. At least 48 mobile homes damaged when they were knocked from their foundations causing gas leaks at West Valley City. A chemical spill occurred at Kennecott Utah Copper's refinery at Magna. Damage estimated at 48.5 million US dollars.

Magna, UT, US - CDI: 6; Salt Lake City, UT, US - CDI: 6

Tectonic Summary

The March 18, 2020 M5.7 earthquake north of Magna, Utah (just west of Salt Lake City) occurred as the result of normal faulting in the shallow crust of the North America plate. The focal mechanism solution for the earthquake indicates slip occurred on a moderately dipping fault striking either to the northwest, or to the south-southeast. The style, location, and depth of slip are consistent with an earthquake on the complex Wasatch fault system. This earthquake is located in the Intermountain seismic belt, a prominent north-south-trending zone of recorded seismicity in the Intermountain West, including the Wasatch Front urban corridor. The ISB region is 1000 km east of the primary North America–Pacific plate boundary which runs along the west coast of the United States.

The Wasatch Front, encompassing Salt Lake City, has experienced infrequent, moderate-to-large earthquakes in the past. There are 26 documented M5+ earthquakes within 250 km of the March 18, 2020 event in the combined University of Utah Seismograph Stations and USGS earthquake catalog, which stretches back to the late 19th century. The largest recorded earthquake was a M6.6 earthquake in March 1934, in Hansel Valley on the north shore of the Great Salt Lake. In September 1962, a M5.0 earthquake occurred in a very similar location to today’s M 5.7 event, with strong shaking observed locally. Geologic investigations of the Wasatch fault indicate that large (M ~7) earthquakes occur about every 1300 years near Salt Lake City, with the most recent large earthquake about 1400 years ago.

Ref #12681:

There were power outages, gas leaks and a chemical spill at Kennecott. The acid spill, and a plume it released into the air, was not threatening the public, officials say.

In West Valley City, 48 mobile homes shifted off of their foundations, displacing residents.

Ref #12684:

Architectural historian staffers from the division have found 126 historic buildings damaged in Wednesday's magnitude 5.7 earthquake or the aftershocks that followed.

Ref #12689:

[damage] at $48.5 million, but that figure is continuing to rise

Inspectors are finding the quake has damaged 107 government buildings, but that doesn't even include homes and businesses. There also are dozens of schools impacted and officials say the Granite School District is getting the worst of it.

Ref #13511:

State estimates show that there could be upwards of $100 million in total building-related damages, contributing to $629 million in total economic losses related to buildings. This does not include damage to public infrastructure.

Ref #13727:

$80 million in economic losses

Ref #13960:

[…] up to $62 million in structural damage and estimates public infrastructure damage at more than $70 million. Most of the $70 million is covered by insurance, but a little more than $18.1 million remains uninsured […] at least two [buildings] were destroyed, and more than 600 buildings were affected by the quake […]The Granite School District suffered losses of over $51 million as a result of building damage […] Most of the damage cost was tied to West Lake Junior High in West Valley City, which the state reported suffered $45 million in damage.

Ref #13961:

economic losses estimated at $629 million