Just the facts, from John Martin, engineer (JAMA)
“At 4:31 A.M. (local time) on Monday, January 17, 1994, a magnitude 6.8 earthquake woke nearly everyone in southern California. The earthquake epicenter was beneath the San Fernando Valley, 20 miles west-northwest of downtown Los Angeles, near the community of Northridge.
Damage was most extensive in the San Fernando Valley, the Simi Valley, and in the northern part of the Los Angeles Basin. After the earthquake, a total of 24,000 dwellings were vacated. The death toll from the quake was 57. The total cost of the earthquake was estimated to be at least $10 billion. The Northridge earthquake is significant since it was the most expensive earthquake and one of the most expensive natural disasters in United States history, yet it occurred on a previously unknown fault.”