The 1994 Northridge earthquake in California had a magnitude of 6.7.
It struck at 4:30:55 a.m. Pacific Standard Time on 17 January 1994, with its epicentre beneath the San Fernando Valley near Reseda, in the greater Los Angeles area. The earthquake lasted about eight seconds and was caused by movement on a previously unknown buried thrust fault, later called the Northridge Blind Thrust Fault or Pico Thrust Fault.
Despite its moderate magnitude compared with California’s largest historical earthquakes, the shock was exceptionally damaging because it occurred beneath a densely populated metropolitan area and produced very strong ground acceleration. Sections of freeways and bridges collapsed, apartment buildings were damaged, and hospitals and other critical facilities were affected.
The earthquake killed 57 people and injured more than 8,700. Damage estimates ranged from roughly $13 billion to $50 billion, making it among the costliest U.S. natural disasters at the time. It also prompted major changes to building codes, seismic retrofits, and emergency planning across California.