Owens Valley is the now-arid valley of the Owens River in eastern California in the United States, to the east of the Sierra Nevada and west of the White Mountains and Inyo Mountains on the west edge of the Great Basin. The mountain peaks on either side reach above 14,000 feet (4,300 m) in elevation, while the floor of the Owens Valley is about 4,000 feet (1,200 m), making the valley one of the deepest in the United States. The Sierra Nevada casts the valley in a rain shadow, which makes Owens Valley "the Land of Little Rain." The bed of Owens Lake, now a predominantly dry endorheic alkali flat, sits on the southern end of the valley.
The 1857 Fort Tejon earthquake occurred at about 8:20 a.m. on January 9 in central and Southern California. One of the largest recorded earthquakes in the United States, with an estimated moment magnitude of 7.9, it ruptured the southern part of the San Andreas Fault for a length of about 225 miles, between Parkfield and Wrightwood.
The 1999 Hector Mine earthquake occurred on October 16 at 02:46:50 PDT with a moment magnitude of 7.1 and a maximum Mercalli intensity of VII. The strike-slip earthquake occurred in a remote part of the Mojave Desert, 47 miles (76 km) east-southeast of Barstow, California, inside the Twentynine Palms Marine Corps Base. Its name comes from a nearby quarry named Hector Mine, which is located 22 kilometers (14 mi) northwest of the epicenter.
The 1992 Landers earthquake occurred on June 28 with an epicenter near the town of Landers, California. The shock had a moment magnitude of 7.3 and a maximum Mercalli intensity of IX (Violent).
The Reno earthquakes of 2008, also known as the "Mogul-Somersett earthquake sequence", occurred in or near the western Reno, Nevada, suburbs of Mogul and Somersett. The earthquake swarm began in February 2008, but the first significant quake of the series occurred on April 15, 2008, registering a 3.6 magnitude. On April 24, 2008, two quakes in the same area registered 4.1 and 4.2. On April 25, 2008, the quake of largest magnitude occurred, registering 4.7 on the Richter scale and causing damage in the immediate area around the epicenter, including destroying 200 feet of a wooden flume supplying water from the Highland Ditch, also known as the Highland Ditch flume. The flume carried up to 50 million US gallons (190,000 m3) a day from the Highland Ditch to Reno's Chalk Bluff Water Treatment Facility and another 5 million US gallons (19,000 m3) to area irrigation users.
The 1999 Chamoli earthquake occurred on 29 March in the Chamoli district in the Indian state of Uttar Pradesh. The earthquake was the strongest to hit the foothills of the Himalayas in more than ninety years. Approximately 103 people died in the earthquake.
The San Jacinto Fault Zone (SJFZ) is a major strike-slip fault zone that runs through San Bernardino, Riverside, San Diego, and Imperial Counties in Southern California. 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 Pacific and North American tectonic plates.
The 2007 Alum Rock earthquake occurred on October 30 at 8:04 p.m. Pacific Daylight Time in Alum Rock Park in San Jose, California. It measured 5.6 on the moment magnitude scale and had a maximum Mercalli intensity of VI (Strong). The event was then the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake, which measured 6.9 on the moment magnitude scale, but was later surpassed by the 2014 South Napa earthquake. Ground shaking from the Alum Rock quake reached San Francisco and Oakland and other points further north. Sixty thousand felt reports existed far beyond Santa Rosa, as far north as Eugene, Oregon.
The 1868 Hayward earthquake occurred in the San Francisco Bay Area, California, United States on October 21. With an estimated moment magnitude of 6.3–6.7 and a maximum Mercalli intensity of IX (Violent), it was the most recent large earthquake to occur on the Hayward Fault Zone. It caused significant damage and a number of deaths throughout the region, and was known as the "Great San Francisco earthquake" prior to the 1906 San Francisco earthquake and fire.
The 1915 Pleasant Valley earthquake occurred at 22:53:21 on October 2 in north-central Nevada. With a moment magnitude of 6.8 and a maximum Mercalli intensity of X (Extreme), it was the strongest earthquake ever recorded in the state.
The 2010 Eureka earthquake occurred on January 9 at 4:27:38 pm PST offshore of Humboldt County, California, United States. The magnitude was measured 6.5 on the Mw scale, and its epicenter was located offshore in the Pacific Ocean 33 miles (53 km) west of the nearest major city, Eureka. Additionally, there was a separate earthquake further offshore of Eureka on February 4 with a slightly lower magnitude of 5.9. It was also the most significant earthquake in the Eureka area in terms of magnitude since the 1992 Cape Mendocino earthquakes. It was felt from Santa Cruz County, California in the south, to Eugene, Oregon in the north and to the east as far as Reno, Nevada.
The 1986 Chalfant Valley earthquake struck southern Mono County near Bishop and Chalfant, California at 07:42:28 Pacific Daylight Time on July 21. With a moment magnitude of 6.2 and a maximum Mercalli intensity of VI (Strong), the shock injured two people and caused property damage estimated at $2.7 million in the affected areas. There was a significant foreshock and aftershock sequence that included a few moderate events, and was the last in a series of three earthquakes that affected southern California and the northern Owens Valley in July 1986.
The Brawley Seismic Zone (BSZ), also known as the Brawley fault zone, is a predominantly extensional tectonic zone that connects the southern terminus of the San Andreas Fault with the Imperial Fault in Southern California. The BSZ is named for the nearby town of Brawley in Imperial County, California, and the seismicity there is characterized by earthquake swarms.
The 2011 Dalbandin earthquake occurred on January 19 at 01:23 AM local time with a moment magnitude of Mw 7.2 and a maximum Mercalli intensity of VI (Strong). The shock occurred in a sparsely populated area of Balochistan, caused moderate damage, three deaths and some injuries.
The 1892 Laguna Salada earthquake occurred at 23:20 Pacific Standard Time on February 23. It had an estimated moment magnitude of 7.1–7.2 and a maximum perceived intensity of VIII (Severe). The shock was centered near the Mexico–United States border and takes its name from a large dry lake bed in Baja California, Mexico. There were no reported casualties, but the event affected the then largely-uninhabited areas of northern Mexico and Southern California.
The 1892 Vacaville–Winters earthquakes occurred in northern California as a large doublet on April 19 and April 21. Measured on a seismic scale that is based on an isoseismal map or the event's felt area, the 6.4 Mla and 6.2 Mla events were assigned a maximum Mercalli intensity of IX (Violent), and affected the North Bay and Central Valley areas. While the total damage was estimated at between $225,000–250,000, one person was killed, but there are no reports on how many people may have been injured. No surface faulting was observed as a result of either strong shocks.
The 1918 San Jacinto earthquake occurred in extreme eastern San Diego County in Southern California on April 21 at 14:32:29 local time. 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.
The 1838 San Andreas earthquake is believed to be a rupture along the northern part of the San Andreas Fault in June 1838. It affected approximately 100 km of the fault, from the San Francisco Peninsula to the Santa Cruz Mountains. It was a strong earthquake, with an estimated moment magnitude of 6.8 to 7.2, making it one of the largest known earthquakes in California. The region was lightly populated at the time, although structural damage was reported in San Francisco, Oakland, and Monterey. It is unknown whether there were fatalities. Based on geological sampling, the fault created approximately 1.5 meters of slip.
The Olancha Earthquake Sequence (2009) was a consecutive series of three earthquakes, with high magnitudes of 5.2, 5.0 and 4.9 respectively, with a number of small shocks between each, to accompany the main "triple shock".
The 2019 Ridgecrest earthquakes of July 4 and 5 occurred north and northeast of the town of Ridgecrest, California and west of Searles Valley, California. They included three main shocks of Mw magnitudes 6.4, 5.4, and 7.1, and many perceptible aftershocks, mainly within the area of the Naval Air Weapons Station China Lake. The first main shock occurred on July 4 at 10:33 a.m. PDT, approximately 18 km (11.2 mi) ENE of Ridgecrest, and 13 km (8.1 mi) WSW of Trona, on a previously unnoticed NE-SW trending fault where it intersects the NW-SE trending Little Lake Fault Zone. This quake was preceded by several smaller earthquakes, and was followed by more than 1,400 detected aftershocks. The M 5.4 and M 7.1 quakes struck on July 5 at 4:08 a.m. and 8:19 p.m. PDT approximately 10 km (6 miles) to the northwest. The latter, now considered the mainshock, was the most powerful earthquake to occur in the state in 20 years. Subsequent aftershocks extended approximately 50 km (~30 miles) along the Little Lake Fault Zone.
