Causing Smaller Earthquakes to Prevent Big Ones?

November 18, 2008

I just got back from Los Angeles, where last week millions of people participated in a gigantic emergency preparedness drill. An Associated Press article reports:

People across Southern California on Thursday looked like they had stepped out of a disaster movie. Children ducked under their desks. Victims with fake blood lay on the ground. First responders sprang into action to treat the "wounded."

The controlled chaos was all part of a mock "Big One" — an earthquake drill billed as the largest in U.S. history and aimed at testing the preparedness of governments, emergency responders and residents.

At 10 a.m., a cast of millions dropped to the ground, covered their heads and held onto furniture. Local television stations interrupted their regular programming to announce the drill and covered it as they would a major earthquake, though with continual reminders that the emergency wasn't real.

The reason for all this is that the L.A. megalopolis sprawls across a network of earthquake faults that makes it highly vulnerable to seismic catastrophes. According to Science Daily, scientists calculate that the probability of a 6.7-magnitude quake striking the Los Angeles area over the next 30 years is 67 percent. (If you’re unclear about what the numbers on the Richter scale mean, here’s an article from our companion site, HowStuffWorks.com, on the subject.) But things could get even worse than that. Scientists say Southern California is overdue for a quake along its portion of the San Andreas Fault. Such a quake could well approximate the one that occurred farther to the north, back in 1857. The 7.9 Fort Tejon earthquake  was so powerful that it reversed the flow of the Kern River and tossed fish from a lake onto the shore. Scientists estimate that a quake that size in the L.A. region today might kill 1,800 people and cause upwards of $200 billion in property damage. And that’s probably being conservative.

So preparedness is important. But wouldn’t it be better if we could somehow prevent big earthquakes from occurring?