The
1994 Northridge earthquake occurred on January 17, at 4:30:55 a.m.
PST and had its
epicenter in
Reseda, a neighborhood in the north-central
San Fernando Valley region of Los Angeles, California. It had a duration of approximately 10–20 seconds. The
blind thrust earthquake had a
moment magnitude (M
w) of 6.7, which produced
ground acceleration that was the highest ever instrumentally recorded in an urban area in North America, measuring 1.8
g (16.7 m/s
2) with strong ground motion felt as far away as
Las Vegas, Nevada, about 220 miles (360 km) from the epicenter. The peak ground velocity in this earthquake at the Rinaldi Receiving Station was 183 cm/s (4.09 mph or 6.59 km/h), the fastest peak ground velocity ever recorded. In addition, two 6.0 M
w aftershocks occurred, the first about one minute after the initial event and the second approximately 11 hours later, the strongest of several thousand aftershocks in all. The death toll was 57, with more than 5,000 injured. In addition, earthquake-caused property damage was estimated to be between $13 and $40 billion, making it one of the costliest natural disasters in U.S. history.