On May 15, 2020 at 4:03:27 local time, a magnitude 6.5 earthquake struck ~ west of Tonopah,

Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...

in the Monte Cristo Range near the

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

-Nevada border. It was Nevada's largest earthquake in 66 years.

Geology

Southwestern Nevada lies within a complex zone of distributed faulting known as the

Walker Lane The Walker Lane is a geologic trough roughly aligned with the California/Nevada border southward to where Death Valley intersects the Garlock Fault, a major left lateral, or sinistral, strike-slip fault. The north-northwest end of the Walker La ...

, which carries up to a quarter of the motion of the

North American Plate The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacific ...

relative to the

Pacific Plate The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. At , it is the largest tectonic plate. The plate first came into existence 190 million years ago, at the triple junction between the Farallon, Phoenix, and Iza ...

. It extends from the

Garlock Fault The Garlock Fault is a left-lateral strike-slip fault running northeast–southwest along the north margins of the Mojave Desert of Southern California, for much of its length along the southern base of the Tehachapi Mountains. Geography Stretc ...

in the southeast along the northeastern flank of the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...

, running parallel to the California–Nevada boundary. The central Walker Lane is characterized by a zone of west–east trending left-lateral strike-slip faults that link northwest–southeast trending dominantly right-lateral strike-slip faults.

Earthquake

The earthquake had a magnitude of 6.5 and a hypocentral depth of only . Shaking was felt throughout California and Nevada, with some reports from as far as

San Francisco San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of Ca ...

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

, and

Salt Lake City Salt Lake City (often shortened to Salt Lake and abbreviated as SLC) is the Capital (political), capital and List of cities and towns in Utah, most populous city of Utah, United States. It is the county seat, seat of Salt Lake County, Utah, Sal ...

. The estimated maximum intensity of shaking was rated as VIII (''Severe'') on the

Modified Mercalli intensity scale The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

. The magnitude was initially reported as M 6.4, but was upgraded about 1 hour later by

USGS The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, a ...

to its current figure. More than 22,300 people reported feeling the earthquake. The

focal mechanism The focal mechanism of an earthquake describes the deformation in the source region that generates the seismic waves. In the case of a fault-related event it refers to the orientation of the fault plane that slipped and the slip vector and is ...

of the earthquake suggests either left-lateral

strike-slip In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic ...

faulting on a west–east trending fault or right-lateral faulting on a north–south trending fault. The distribution of aftershocks supports the first of these options. The earthquake lies close to the projected eastward continuation of the Candelaria fault, which is known to have been

active Active may refer to: Music * ''Active'' (album), a 1992 album by Casiopea * Active Records, a record label Ships * ''Active'' (ship), several commercial ships by that name * HMS ''Active'', the name of various ships of the British Royal ...

during the

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

period. It also lies close to the northern end of the north–south trending Eastern Columbus Salt Marsh fault.

Aftershocks

Within the first 5 hours proceeding the main shock, there were 6

aftershocks In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in the same area of the main shock, caused as the displaced crust adjusts to the effects of the main shock. Large earthquakes can have hundreds to thousand ...

measuring magnitude 4.5 or higher, the highest being a 5.1. On November 13, at 1:13 a.m. local time, a magnitude 5.3 aftershock took place. It is the largest aftershock of the sequence.

Impacts

Since the earthquake occurred in a remote and relatively uninhabited area, few people were exposed to severe shaking, hence no casualties occurred. The earthquake cracked

U.S. Route 95 US Route 95 (US 95) is a major north–south United States Numbered Highways, US Highway in the western United States. It travels through the states of Arizona, California, Nevada, Oregon, and Idaho, staying inland from the Pacific Coast ...

between

Reno Reno ( ) is a city in the northwest section of the U.S. state of Nevada, along the Nevada-California border, about north from Lake Tahoe, known as "The Biggest Little City in the World". Known for its casino and tourism industry, Reno is the c ...

and

Las Vegas Las Vegas (; Spanish for "The Meadows"), often known simply as Vegas, is the 25th-most populous city in the United States, the most populous city in the state of Nevada, and the county seat of Clark County. The city anchors the Las Vegas ...

, causing it to be temporarily closed. The highway was reopened 10 hours after repair operations. Several post-earthquake field reconnaissance teams documented surface fault expressions, rock falls, subsidence features, and other geologic and geotechnical effects in the Columbus Salt Marsh to the west of U.S. Route 95 and surrounding areas. In Tonopah, displaced items, broken windows, cracked asphalt, masonry, and drywall were reported.

References

{{Earthquakes in the United States Monte Cristo Range earthquake Earthquakes in Nevada May 2020 events in the United States Monte Cristo Range earthquake Monte Cristo Range earthquake

Geology

Earthquake

Aftershocks

Impacts

See also

References