1994 Northridge USA

Magnitude
6.7
Focal depth
18.0
Date (UTC)
1994-01-17
Time (UTC)
12:30:55
People killed
33
GEMECD contributing partner
SPA
At 4:31 A.M. local time, Monday, January 17, 1994 the Northridge earthquake struck the San Fernando Valley region of Southern California with a moment magnitude measured at 6.7 and focal depth of 19 km.

The earthquake was centered 32 km west-northwest of Los Angeles along a south-dipping, blind thrust fault. Little if any surface faulting was produced.

The earthquake was felt throughout much of southern California and as far away as Turlock, California; Las Vegas, Nevada; Richfield, Utah and Ensenada, Mexico.

The maximum recorded acceleration exceeded 1.0g at several sites in the area with the largest value of 1.8g recorded at Tarzana, about 7 km south of the epicenter.

A maximum uplift of about 15 cm occurred in the Santa Susana Mountains and many rockslides occurred in mountain areas, blocking some roads. Some ground cracks were observed at Granada Hills and in Potrero Canyon. Some liquefaction occurred at Simi Valley and in some other parts of the Los Angeles Basin.

Impact summary

Sixty people were killed, more than 7,000 injured, 20,000 homeless and more than 40,000 buildings damaged in Los Angeles, Ventura, Orange and San Bernardino Counties.

Severe damage occurred in the San Fernando Valley: maximum intensities of (IX) were observed in and near Northridge and in Sherman Oaks.

Lesser, but still significant damage occurred at Fillmore, Glendale, Santa Clarita, Santa Monica, Simi Valley and in western and central Los Angeles.

Damage was also sustained to Anaheim Stadium. Collapsed overpasses closed sections of the Santa Monica Freeway, the Antelope Valley Freeway, the Simi Valley Freeway and the Golden State Freeway.

Fires caused additional damage in the San Fernando Valley and at Malibu and Venice.

Preliminary estimates of damage are between 13 and 20 billion U.S. dollars.

(From USGS' Significant Earthquakes of the World 1994 at http://earthquake.usgs.gov/earthquakes/states/events/1994_01_17.php)

Demographics

Population
Number of households
Number of households affected by shaking
Total number of buildings
114000
Total number of buildings affected by shaking
Base date

Human impact

People injured
7000
People seriously injured
138
People missing
People killed
33
People dying post catastrophe
People homeless
20000

Building damage

Total number of buildings destroyed
Number of buildings damaged
Number of dwellings destroyed
Number of dwellings damaged

Socioeconomic loss (millions of USD)

Direct economic loss
24000.0
Indirect economic loss
44000.0
Insured loss
15300.0

Key facts

Event name
Northridge
Event ID
199401171230
Country
USA
Region in the country
California
World region
North America
Epicentral coordinates (long/lat)
POINT(-118.54 34.21)
Date (UTC)
1994-01-17
Time (UTC)
12:30:55
Day of the week (local)
Monday
Magnitude
6.7
Focal depth
18.0
Magnitude units
Moment (Mw)

Main data source studies

Study name Author(s) Study publication date
Lizundia et al. 1997 URM Study Lizundia, Bret; Holmes, William T.; Longstreth, Margaret; Kren, Alan; Abrams, Daniel P. 1997-07-31 22:00:00
Schierle 2003 Residential Woodframe Dwellings Study Schierle, G. G. 2002-12-31 23:00:00
Tolles et al 1996 Historical Adobe Study Tolles, E. Leroy; Webster, Frederick A; Crosby, Anthony; Kimbro, Edna E. 1995-12-31 23:00:00
GeoArchive Photographic Study (CAR)