Earthquake fault heightens California tsunami threat, experts say

The earthquake fault cuts through the heart of Ventura’s quaint downtown, past the ornate hilltop City Hall and historic Spanish-era mission before heading into the Pacific Ocean.

For decades, some seismic experts believed the Ventura fault posed only a moderate threat and was incapable of producing a major temblor.

But research in recent years shows that the fault is extremely dangerous, capable of producing an earthquake as large as magnitude 8 as well as severe tsunamis that until now experts didn’t believe were possible from a Southern California quake.

Such a big earthquake on the fault estimated to occur every 400 to 2,400 years, experts said. The last sizable quake on the Ventura area hit about 800 years ago. Large temblors occur on this fault less frequently than on the San Andreas fault, which has long been considered the state’s most dangerous.

‘The Big One’ Earthquake Will Hit L.A. Harder Than We Thought, Scientists Say

• Simulation of a magnitude-7 quake on the San Andreas Fault. Seismic waves radiate outward, then deep into L.A.

A  seismology study by scientists from Stanford and MIT, published in the journal Science on Friday, finds that if the Big One hits the San Andreas Fault near Palm Springs, some seismic waves will travel near the path of the 10 Freeway into the heart of Los Angeles, where the city and its suburbs will suffer stronger ground motions than previously believed. Downtown L.A. will endure three times the shaking of surrounding areas, scientists now say.