The 1918 San Jacinto earthquake occurred in extreme eastern

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on April 21 at . The shock had a moment magnitude of 6.7 and a maximum Mercalli intensity of IX (''Violent''). Several injuries and one death occurred with total losses estimated to be $200,000.

Tectonic setting

The San Jacinto Fault Zone is a major strike-slip fault zone that runs through

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, Riverside,

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, and Imperial counties in

. The SJFZ is a component of the larger San Andreas transform system and is considered to be the most seismically active fault zone in the area. Together they relieve the majority of the stress between the

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and

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tectonic plates.

Damage

Many of the buildings in San Jacinto's business district were of poor construction, and all but one frame building and one concrete building collapsed, though high-quality structures did not experience serious damage. Minor damage to other buildings within of San Jacinto also occurred. Roadways and

irrigation Irrigation (also referred to as watering of plants) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has bee ...

canals also sustained damage and small sand blows were seen on a farm northwest of San Jacinto. The earthquake occurred on a Sunday afternoon when most of the businesses in San Jacinto were closed and void of customers. The business district had the greatest damage, though Hemet was also severely damaged. Damage to chimneys, windows, and plaster walls occurred to buildings and structures within of San Jacinto. Some of the damage that was inspected included landslides, partially collapsed buildings, and damaged irrigation canals and roads. Ground cracks were observed near the banks of the San Jacinto River.

References

Sources * *

External links

Could a great quake strike on the enigmatic San Jacinto fault?
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Temblor, Inc. Temblor, Inc. is a tech company that provides information about earthquakes and enables users to both see what the seismic hazard is at their home, and learn about precautions to help lessen the risk. The company has released a web app and a mobi ...

* {{Earthquakes in the United States Earthquakes in California 1918 earthquakes 1918 in California 1918 natural disasters in the United States

Tectonic setting

Damage

See also

References

External links