California's Earthquake History

Although previously earthquakes have been documented—such as significant movement top top the southern San Andreas fault every the way back come the 1600s—the more quickly reported earthquake in California was on July 28, 1769, provided by members that a Spanish exploration to graph a land route from mountain Diego come Monterey. Members that the exploration led by Gaspar de Portolá to be camped follow me the Santa Ana River as soon as they felt a solid earthquake.

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Based on descriptions of the quake, the was likely a center or solid earthquake. Some explained the shiver in expedition diaries as violent, occurring over the next several days, saying aftershocks. Return the magnitude and also epicenter are unclear, by to compare thedescriptions with an ext recent events, the quake may have been comparable in strength to the 1933 lengthy Beach or 1987 Whittier Narrows earthquake.

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Timeline of historic Earthquakes in California

Although most of California's quakes are little in magnitude and cause little or no damage, California experiences an ext than 100 every day!

Many noteworthy shakers—moderate or major earthquakes in California—have made background and are still remembered and also talked around today.

Take a look at noteworthy temblors in our state’s recorded history by viewing this California earthquake history timeline.


Earthquake magnitude Scale
This list of earthquakes in California is significant with colored one indicating magnitude. Whereby the specific magnitude range (e.g., Richter scale or minute magnitude ) was noted in the source material, the notation has been included, together well, in the summaries. The scale is together follows:

Magnitude 4.0 come 4.9

Magnitude 5.0 come 5.9

Magnitude 6.0 come 6.9

Magnitude 7.0 and also greater


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Antelope sink
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On the afternoon the July 8, 2021, at the very least several dozen earthquakes struck tiny Antelope Valley, which is in Inyo national Forest, about 20 mile southwest of smith Valley, Nevada. The quakes were a an outcome of regular faulting and strike on slide faults near the Antelope valley fault, which operation north-south along the Sierra Nevada variety front. The largest, a 6.0 magnitude, occurred along the east edge that the Sierra Nevada, a significant physiographic boundary along the California-Nevada border.

The magnitude 6.0 earthquake was extensively felt, with reports as much away together the san Francisco bay Area and also Sacramento in California, and also Carson City in Nevada. Aftershocks continued to it is in felt into the night, with a magnitude 4.5 aftershock reported approximately 10:30 p.m. Damages from the earthquakes on July 8 was minor and included a rockslide in Coleville and also items falling native shelves in adjacent stores.

Even quakes the don’t cause major damage room a reminder the California is earthquake county, and it’s important to be prepared. Learn how an individual preparedness and practicing an important steps to safety can aid you be ready. And also if you own your home, among the ideal things come do prior to the next large earthquake strikes is to combine it with a seismic retrofit. Gain started in ~ StrengthenMyHouse.com.

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Westmorland
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A swarm that hundreds of little earthquakes south of the Salton Sea brought about thousands the local people to feel “strong” shaking. The very first quake top top September 30, to mark in the late afternoon, was a M3.0. The largest, a M4.9, struck in ~ 5:31 p.m. The swarm lasted for numerous days, stability at a low price by Oct. 3. There were no reports the damage, but the swarm is a reminder to be earthquake ready.

According to USGS, this earthquake swarm is in one area of diffuse seismic task between the san Andreas fault to the north and the royal fault to the south. Past swarms in this area incorporate the 1981 Westmorland swarm, where the highest magnitude was a 5.8, and the 2012 Brawley Storm, which included a M5.4 quake. In august of 2020, a swarm that earthquakes had likewise struck in the same area, the largest being a magnitude 4.6 in ~ Bombay Beach.

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South El Monte
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A magnitude 4.5 earthquake to win in Los Angeles, about 10 miles east of the Los Angeles public Center, late at night on September 18. It was widely felt throughout the region, even as much south as mountain Diego, and also was complied with by several aftershocks.

The area is seismically active—this quake was not far from the epicenter that the 1987 Whittier Narrows earthquake, i beg your pardon caused comprehensive damage. In 2014, the La Habra quake struck along the Puente Hills thrust fault, displacing residents. The thrust fault is thought about especially dangerous together it runs along a dense urban area (downtown Los Angeles).

Luckily, there to be no reports of major injuries or damage from this quake, however it’s a reminder that as soon as there is shaking, you have to practice personal preparedness and also Drop, Cover, and also Hold On until the shiver stops.

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Lone jaw
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After a foreshock through a size of 4.6 two days earlier, on June 24, a size 5.8 earthquake struck around 12 mile southeast the Lone Pine, in Inyo County. People felt the shower as far away as 350 miles northwest in san Francisco and also 230 miles eastern in las Vegas. Human being reported emotion shaking as far as Sacramento and Los Angeles, too. Campers at mount Whitney were evacuated after a rockslide—which was triggered by the shaking—caused “truck-sized boulders” come fly off the mountain, through one landing top top the trailhead. CEA had about 150 policyholders in the influenced area.

According come the Los Angeles Times, a quake the this size “may reason slight and moderate damages in well-built plain structures and considerable damage in poorly built or badly designed structures and also may rest chimneys.” If you own an enlarge home, that is encourage to retrofit the to make it an ext resistant against shaking. Learn more at StrengthenMyHouse.com.

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Searles valley
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On June 3, 2020, a magnitude 5.5 earthquake struck around 13 miles from Ridgecrest, and 10 miles southern of Searles Valley, in the Mojave Desert.

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Dr. Lucy Jones tweeted the it to be a large, late aftershock of the 2019 Ridgecrest sequence, which produced quakes as large as M6.4 and also M7.1. Citizens in the area expressed anxiety around this brand-new shaker, noting they never know if it is one aftershock or a authorize of a bigger quake come come. Learn exactly how to be better prepared come survive and recover from an earthquake by reading about what to do prior to an earthquake strikes.