Images of devastating earthquakes strike fear into anyone who lives near an earthquake fault zone, but what's even more terrifying is that scientists don't know when the next big one will hit, CBS News Correspondent Sandra Hughes reports.
"We still don't know how to predict earthquakes, and most of the recent theories seem to indicate that it may be a long time or perhaps never [before we do]," said seismic engineer Tom Heaton.
But scientists in southern California, leading the way in earthquake study, are closer to predicting where the next major quake will strike.
Using global satellites that read information from some 600 ground sensors, it's possible to gauge how much the earth shifts over time and where energy builds along a fault line, setting off an earthquake.
Heaton said knowing where an earthquake will strike - even if we don't know when - was valuable since "It allows us to focus our long-term preparedness. If you live with earthquakes, you've got to be ready for them at any instance."
And right now, getting ready means making stronger buildings.
Kobe, Japan, where a devastating 7.2 quake hit in 1997, now has some strictest building codes in the world. So does Los Angeles, where they're spending hundreds of millions of dollars to retrofit downtown. City Hall is literally being raised up and placed on rubber rollers to make it safer from earthquakes.
In about five years, southern California will test an alarm system. It would sound when a quake hits, warning residents in the path of the shock waves to take cover - the idea being that even a moment's notice is better than none.
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