If you live in California then one question we all have is "when is the Big One due"?
A new report shows that it might be sooner than expected.
New research shows that major earthquakes have struck southern California far more frequently than previously thought -- and the next one could be just around the corner.
The study from geologists at the University of California Irvine and Arizona State University showed that massive quakes -- of magnitude 6.5 or greater -- have hit the region's San Andreas fault line at intervals of between 45 and 144 years.
With the last major earthquake in 1857, that means Southern California is overdue a massive quake.
"The next earthquake could be sooner than later," Lisa Grant Ludwig, a UC Irvine earthquake expert and co-author of the study, told The Los Angeles Times. "It was thought that we weren't at risk of having another large one any time soon. Well, now, it might be ready to rupture."
Previously, experts that thought the quakes occurred once every 250 years to 450 years.
The team of scientists obtained their results by studying ancient charcoal samples in the Carrizo Plain portion of the San Andreas fault line.
The charcoal fragments during earthquakes, so dating the fragments can pinpoint the time of earthquakes. The results were published Friday in Geology, a journal.
A quake of just 7.8 magnitude -- less than the 1857 earthquake -- could spread chaos through some of California's biggest cities, including Los Angeles, according to a study by the state Emergency Management Agency.
"You would see buildings collapse, you'd see people trapped, you'd see roadways collapse. You'd see widespread destruction," Kelly Huston, assistant agency secretary for public and crisis communication, told Fox News.
The 1857 quake is known as the Fort Tejon quake, though it is believed to have originated in Parkfield, Calif. The earthquake tore south on the San Andreas fault for 200 miles, near the northern edge of what is now LA County, then headed east toward the Cajon Pass.
The shaking, which lasted between one minute and three minutes, was so powerful that the soil liquefied, causing trees to sink into the earth.
At the time, LA's population was a mere 4,000. Now it's 9.9 million.
The new information "puts the exclamation point" on the importance of residents and policymakers preparing for a major earthquake, Ludwig told Agence-France Presse.
Ludwig is in favor of policies mandating earthquake risk signs on unsafe buildings, and making inspectors in home-sale transactions reveal degrees of risk.
Still, not everyone is quite so alarmed by the study's findings. Morgan Page, a geophysicist with the United States Geological Society, told Fox News that more research needs to be done before the theories about the San Andreas quakes can be accepted as definitely true.
The study is ""rather controversial. Some people support the work, and some people think there may be problems with it," she told Fox News.
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