Chilling image of a bunch of clocks salvaged from the severely damaged (later demolished) 3-month old Olive View Hospital -- frozen at the time of the earthquake:
http://framework.latimes.com/2011/02/09/sylmar-earthquake/#/6USGS data on the quake (now estimated to have been the same magnitude as the '94 Northridge quake.
http://earthquake.usgs.gov/earthquakes/states/events/1971_02_09.php.