From architect Roger K. Lewis in the Washington Post:
The sight of thousands of collapsed structures in Port-au-Prince, Haiti, may lead you to wonder whether a strong earthquake could cause equally widespread, catastrophic building collapse in an American city.
Fortunately, diligent engineering, up-to-date building codes and sound construction techniques ensure that many structures in America would withstand earthquake forces. But could some of our buildings, especially old ones, be vulnerable if seismic forces are sufficiently strong?
Age, per se, does not determine earthquake survivability, which instead depends on the inherent strength of a building's overall structural framework. Old or new, any poorly engineered or cheaply constructed building always will be vulnerable to severe earthquake-induced damage or collapse.