Los Angeles Blind Thrusts
Southern California, USA · blind thrust · 1439.2 km of mapped active fault in 38 traces
background as of 7 November 2026.
consistent with baseline
| Window | the last 30.0 days |
|---|---|
| Earthquakes counted | 0 at M4.5 or above |
| Expected in that window | 0.03 |
What this system normally does
From 1995 to 2025 the catalogue holds 12 earthquakes of M4.5 or larger attributable to this system: about 0.40 a year. That figure is what "elevated" on this page is measured against.
The fault itself
| Mapped length | 1439.2 km |
|---|---|
| Traces | 38 |
| Tectonic setting | blind thrust |
| Slip types | Reverse, Sinistral-Reverse, Dextral-Reverse |
| Depth attributed to it | down to 50.0 km |
| Extent | 33.60 to 34.45 latitude, -119.21 to -117.44 longitude |
Recorded history
NOAA's hazard records hold 13 significant earthquakes and 3 tsunamis attributed to this system since 1855.
The deadliest was the 11 March 1933 magnitude 6.3 earthquake (California: Long Beach), which killed 120 people.
The strongest earthquake on record here was magnitude 6.7, on 17 January 1994 (California: Northridge).
The most recent entry is the 29 March 2014 magnitude 5.1 earthquake (California: la Habra, Brea, Fullerton).
Across the entries that record a death toll, 254 people died.
| Date | What | Where | Toll |
|---|---|---|---|
| 11 March 1933 | magnitude 6.3 earthquake | California: Long Beach | 120 dead, $41 million damage |
| 9 February 1971 | magnitude 6.5 earthquake | California: San Fernando | 65 dead, $505 million damage |
| 17 January 1994 | magnitude 6.7 earthquake | California: Northridge | 57 dead, 40,000 homes destroyed, $40,000 million damage |
| 17 January 1994 | tsunami (waves to 0.1 m) | West Coast, Usa | 57 dead, 40,000 homes destroyed, $40,000 million damage |
| 1 October 1987 | magnitude 5.7 earthquake | California: Whittier | 8 dead, $358 million damage |
| 28 June 1991 | magnitude 5.1 earthquake | California: Arcadia, Glendale, Los Angeles | 2 dead, $34 million damage |
| 31 August 1930 | tsunami (waves to 3 m) | S. California | 1 dead, damage under $1 million |
| 31 August 1930 | magnitude 5.2 earthquake | California: Southern | 1 dead, damage under $1 million |
| 4 October 1987 | magnitude 4.8 earthquake | California: Whittier, Pasadena | 1 dead, damage $1 to 5 million |
| 11 July 1855 | magnitude 6.0 earthquake | California: Los Angeles | 1 homes destroyed, damage $1 to 5 million |
| 21 February 1973 | magnitude 5.7 earthquake | California: Oxnard | $1 million damage |
| 28 February 1990 | magnitude 5.5 earthquake | California: S, Claremont, Covina | $13 million damage |
| 29 July 2008 | magnitude 5.4 earthquake | California: Los Angeles | damage $1 to 5 million |
| 29 March 2014 | magnitude 5.1 earthquake | California: la Habra, Brea, Fullerton | $11 million damage |
| 11 July 1855 | tsunami | S. California | 1 homes destroyed, damage $1 to 5 million |
| 9 September 2001 | magnitude 4.2 earthquake | California: Los Angeles | damage under $1 million |
A dash means NOAA recorded no number, not that nobody died. Older entries are fewer because fewer were written down, not because less happened.
Recorded history: NOAA NCEI hazard databases, public domain, retrieved 2026-10-22.
Who to listen to if you live here
California Geological Survey is the agency that tells people on this system what to do. https://www.conservation.ca.gov/cgs/earthquakes (in English)
Other systems in Southern California, USA
Where these numbers come from
Fault geometry, length and segment counts: GEM Global Active Faults Database (GEM GAF-DB), GEM Foundation, https://github.com/GEMScienceTools/gem-global-active-faults Licence: CC-BY-SA-4.0. Figures derived from it here are offered under the same licence. Earthquake counts, magnitudes and depths: United States Geological Survey, public domain. The activity judgement is ours, computed from those two inputs, and is not a statement by either agency.