The 1992 Landers earthquake occurred on Sunday, June 28 with an epicenter near the town of

Landers Landers may refer to: People * Landers (surname), a list of people surnamed Landers (including fictional people) Places * Landers, California, United States * Landers Peaks, group of peaks in the northern portion of Alexander Island, Antarct ...

, California, in San Bernardino County. The shock had a

moment magnitude The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 pape ...

of 7.3 and a maximum

Mercalli intensity 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 ...

of IX (''Violent'').

Earthquake

At 4:57 a.m. local time (11:57 UTC) on June 28, 1992, a

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

7.3 earthquake awoke much of Southern California. Though it turned out it was not the so-called " Big One" as many people would think, it was still a very strong earthquake. The shaking lasted for two to three minutes. Although this earthquake was much more powerful than the

1994 Northridge earthquake The 1994 Northridge earthquake was a moment 6.7 (), blind thrust earthquake that occurred on January 17, 1994, at 4:30:55 a.m. PST in the San Fernando Valley region of the City of Los Angeles. The quake had a duration of approximately ...

, the damage and loss of life were minimized by its location in the sparsely-populated

Mojave Desert The Mojave Desert ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily in ...

. The earthquake was a right-lateral strike-slip event, and involved the rupture of several different faults over a length of . The names of those that were involved are the Johnson Valley, Kickapoo (also known as Landers), Homestead Valley, Homestead/Emerson, Emerson Valley and Camp Rock faults. The

surface rupture In seismology, surface rupture (or ground rupture, or ground displacement) is the visible offset of the ground surface when an earthquake rupture along a fault affects the Earth's surface. Surface rupture is opposed by buried rupture, where the ...

extended for , with a maximum horizontal displacement of and a maximum vertical displacement of .

Damage

Damage to the area directly surrounding the epicenter was severe. Roads were buckled. Buildings and chimneys collapsed. There were also large surface fissures. To the west in the

Los Angeles Basin The Los Angeles Basin is a sedimentary basin located in Southern California, in a region known as the Peninsular Ranges. The basin is also connected to an anomalous group of east-west trending chains of mountains collectively known as the Tr ...

damage was much less severe. The majority of the damage in the Los Angeles area involved items that had fallen off shelves. Unlike the

nineteen and a half months later, no freeway bridges collapsed because of the epicenter's remote location. Electricity was cut to thousands of residents but was generally restored within two to three hours. There was also some damage to homes from water displaced from swimming pools. Loss of life in this earthquake was minimal. Two people died as a result of heart attacks, and a 3-year-old boy from

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

, who was visiting

Yucca Valley Yucca Valley is an List of municipalities in California, incorporated town in San Bernardino County, California, San Bernardino County, California, United States. The population was 20,700 as of the 2010 United States Census, 2010 census. Yucca ...

with his parents, died when bricks from a chimney collapsed into a living room where he was sleeping. More than 400 people sustained injuries as a result of the earthquake.

Related events

The quake was preceded by the 6.1 magnitude Joshua Tree earthquake at 4:51 on April 23, 1992 (UTC), which was south of the future Landers epicenter. The 6.5 magnitude Big Bear earthquake, which hit about three hours after the Landers mainshock, was originally considered an aftershock. However, the

United States Geological Survey 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, ...

determined that this was a separate, but related, earthquake. These two earthquakes are considered a regional earthquake sequence, rather than a main shock and aftershock. The magnitude 5.7 Little Skull Mountain (LSM) earthquake the following day, June 29, 1992, at 10:14 UTC near

Yucca Mountain Yucca Mountain is a mountain in Nevada, near its border with California, approximately northwest of Las Vegas. Located in the Great Basin, Yucca Mountain is east of the Amargosa Desert, south of the Nevada Test and Training Range and in the Ne ...

, Nevada, is also considered part of the regional sequence and may have been triggered by surface wave energy produced by the Landers earthquake. Foreshock activity, in the form of a significant increase in micro-earthquakes, was observed at Little Skull Mountain following the Landers earthquake, and the activity continued until the main LSM earthquake.

Theories

The Landers earthquake and the other large quakes associated with it in the Mojave region have been attributed to two possible long-term trends. One of these is that the

San Andreas Fault The San Andreas Fault is a continental transform fault that extends roughly through California. It forms the tectonics, tectonic boundary between the Pacific Plate and the North American Plate, and its motion is Fault (geology)#Strike-slip fau ...

may be in the process of being replaced as the plate boundary (between the North American Plate and the Pacific Plate) by a new trend across the Mojave and east of the

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

. The other is that these quakes were a manifestation of the propagation of rifting coming up from the

Gulf of California The Gulf of California ( es, Golfo de California), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Bermejo''), is a marginal sea of the Pacific Ocean that separates the Baja Ca ...

In popular culture

The earthquake is featured in the

television documentary Television documentaries are televised media productions that screen documentaries. Television documentaries exist either as a television documentary series or as a television documentary film. *Television documentary series, sometimes called d ...

series produced by

GRB Entertainment GRB Entertainment, Inc. (doing business as GRB Studios since October 9, 2018) is an American film and television production company and distributor, known for producing and distributing reality and documentary programs such as '' Intervention'' ...

, aired on

The Learning Channel TLC is an American cable television channel owned by Warner Bros. Discovery. First established in 1980 as The Learning Channel, it initially focused on educational and instructional programming. By the late 1990s, after an acquisition by the own ...

and other television channels around the world, about natural disasters titled ''

Earth's Fury ''Earth's Fury'' (also known as ''Anatomy of Disaster'' outside the United States) is an American documentary television series that ran on The Learning Channel from February 24, 1997 to November 17, 1998. Produced by GRB Entertainment, each epi ...

'' (also known internationally as ''Anatomy of Disaster'') in an episode entitled "Earthquake!"

References

External links

Landers Earthquake
at the ''Southern California Earthquake Data Center''

at the ''Southern California Earthquake Data Center''
Studying the M7.3 1992 Landers, California earthquake: original forms and initial modifications
– Ramon Arrowsmith * {{DEFAULTSORT:Landers Earthquake, 1992

1992 File:1992 Events Collage V1.png, From left, clockwise: 1992 Los Angeles riots, Riots break out across Los Angeles, California after the Police brutality, police beating of Rodney King; El Al Flight 1862 crashes into a residential apartment buildi ...

1992 earthquakes Strike-slip earthquakes 1992 in California History of the Mojave Desert region Geology of San Bernardino County, California History of San Bernardino County, California