Despite recent shaking, California remains in an 'earthquake drought'

LOS ANGELES -- Despite an unusual number of modest earthquakes this year in Southern California, the state overall remains in the midst of a drought of major earthquakes.

There have been no significant damaging earthquakes underneath California's oldest, most populous cities in the last 30 years, sparing places like Los Angeles, San José, San Francisco, Long Beach and Oakland from seismically related deaths and destruction.

That's a stark contrast to the prior three decades, when earthquakes in suburban or mountainous areas caused catastrophic damage in the urban infrastructure, causing freeway and building collapses and resulting in the deaths of scores of people.

"If you take the last 30 years as your definition of how often you should expect to be feeling earthquakes, you are underestimating the long-term rate," said seismologist Lucy Jones, a Caltech research associate. "Since Northridge, in the L.A. area, we've been seeing fewer earthquakes, and having fewer damaging ones, than the long-term rate would imply."

30 years, but how much longer?

Between 1964 and 1994, Los Angeles faced two big earthquakes, which both hit the suburban San Fernando Valley hard: the of 1971, which resulted in 64 deaths; and the of 1994, in which about 60 people died. The Northridge quake caused up to.