Newport-Inglewood Fault

The Newport-Inglewood Fault is a right-lateral fault in Southern California. The fault extends for 75 kilometers (47 mi) from Culver City southeast to Newport Beach at which point it runs out into the Pacific Ocean. The fault can be seen on the Earth's surface as line of hills extending from Signal Hill to Culver City. The fault has a slip rate of approximately 0.6 millimeter/year (0.02 in/year) and is predicted to be capable of a 6.0–7.4 magnitude earthquake on the moment magnitude scale.

The fault was first identified after a 4.9 magnitude quake struck near Inglewood, California on June 21, 1920. Due to the lack of earthquake-resistant construction in southern California at this time, this quake caused considerable damage in the Inglewood area and was a preview of what was to come almost 13 years later. The Long Beach earthquake occurred on March 10, 1933, centered along the southern segment of this fault, and registering a magnitude 6.3; this quake killed 115 people and was the second most deadly earthquake in California history, after the 1906 San Francisco earthquake. Seventy schools in the Long Beach and Compton area were destroyed and an additional 120 were heavily damaged by the quake; had this tremor struck during school hours, the death toll would have been much higher, some estimates as high as 1000. In response to the poor performance of school structures, the California legislature passed the Field Act in April, mandating earthquake-resistant construction for all new school buildings.

On September 9, 2001, a magnitude 4.2 earthquake was reported at the northern end of the Newport-Inglewood fault, near Century City.

On May 17, 2009, at 8:39 PDT, a 4.7 earthquake was centered in the unincorporated community of Lennox, very close to the estimated location of the 1920 Inglewood earthquake. The earthquake was felt as far away as San Diego and Las Vegas. An aftershock measuring 4.0 occurred on May 19, 2009, at 3:49 PDT in nearly the same location. As of June 3, 2009, more than a score of aftershocks had been measured at or near the point of the original earthquake on May 17. The Newport-Inglewood fault may have been responsible for these quakes, but further study is needed to determine the source fault.

On November 5, 2010 at 9:06 a.m. local time, a magnitude 3.7 quake originated on this fault, centered two miles south of Long Beach, CA. No damage was reported.

On August 18, 2011 at 2:43 p.m. local time, a magnitude 3.2 quake originated on this fault, centered two miles southeast of Long Beach. No damage was reported.

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