L.A. at Risk?
The 1680 quake had relatively little effect, since it struck the then-uninhabited Palm Springs area.
But a lot has changed in the intervening time.
In one likely scenario, a magnitude 7.8 earthquake would strike near the Salton Sea in the Coachella Valley, which is located east of San Diego and Los Angeles, Jones said (California map).
Extending north for approximately 200 miles (320 kilometers), the predicted quake would topple buildings, destroy roads and railways, ignite wildfires, and trigger landslides, she added.
In addition to causing numerous deaths, such a quake would trigger rampant destruction that would leave tens of thousands homeless and the area's transportation corridors to the rest of the country completely shut down.
"The largest growing area of Southern California is right next to the fault," Jones said. "There are way more people at risk from this earthquake than from hurricanes."
But the damage would not be limited to the Coachella Valley.
"If the earthquake nucleates at the Salton Sea and ruptures north, much of the seismic energy will be funneled into the Los Angeles Basin, causing very serious shaking and damage to the city," said Yuri Fialko, a geophysicist at the Scripps Institution of Oceanography.
If that happens, "this would be a very significant economic and social issue for the nation," Jones said.
Since no one can predict exactly when such an earthquake might strike—or do anything to prevent one—the best defense is proper preparation, Jones added.
Jones and her team's findings will eventually become the foundation for statewide emergency response demonstrations and preparedness efforts, she said.
"We want emergency preparedness to become a part of the Southern California consciousness. This earthquake is inevitable, but the disaster is not."
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