![]() Vidale, the former director of the Pacific Northwest Seismic Network, treated the research cautiously because the San Andreas Fault and Cascadia Subduction Zone move differently. Seismologist John Vidale of the University of Southern California said Goldfinger is "out on the edge" with his findings. The margin of error means that what appears to be a one-two punch of Pacific Coast earthquakes could potentially have been separated by years or even decades. ![]() Goldfinger acknowledged that carbon dating has limitations on its precision. It just isn’t on the radar anywhere yet." "So one fault triggering another, or even becoming synchronized with the other for a period of time, is not a fantastical scenario. ![]() "When you have two big faults that connect directly, there's a pretty high probability they’re going to interact in some way," Goldfinger said. The two faults touch at a place called the Mendocino Triple Junction, which is offshore of Mendocino County, California. Oregon State University The Cascadia Subduction Zone and northern San Andreas Fault meet at a place called the Mendocino Triple Junction. The northern San Andreas Fault also went off in 1906, causing the Great San Francisco Earthquake, but the Cascadia fault stayed quiet then. Goldfinger said it looks like the San Andreas went off around the same year. The most recent Cascadia megaquake happened in 1700. He added that his analysis of landslide traces found no evidence for the stress transfer working in reverse - from south to north. The vast majority of great Cascadia quakes during that period have a correlation on the San Andreas Fault. Goldfinger said he found nine to eleven instances over roughly the last 3,000 years where a Cascadia earthquake seems to have triggered a San Andreas quake. "They seem to have happened at more or less the same time." "I've been working on the chronology for San Andreas and Cascadia and some of the events I can't really tell them apart in time," Goldfinger explained. For this investigation, Goldfinger compared the sediment records from the southern end of the Cascadia fault zone with the northern San Andreas Fault, which extends under the San Francisco Bay area. Those earthquake traces can be carbon dated. The long, skinny tubes of mud contain deposits from underwater landslides caused by long ago earthquakes. Goldfinger's team reconstructs the history of great earthquakes along the West Coast by pulling sediment samples from lake bottoms and offshore underwater canyons. The marine geologist said a major quake from the offshore Cascadia fault zone could trigger California's famous San Andreas Fault. But in an interview this fall, Goldfinger said the miniseries was possibly prescient about one thing. The star-studded disaster movie was dismissed by West Coast earthquake experts at the time as " impossible," mythical " fiction." And there were almost too many inaccuracies to count. By the end, part of California fell into the ocean.Ĭredit Copyright 2004 NBC /t7z5kmh The earthquake disaster miniseries scored high ratings when it first aired in 2004. That initial rupture triggered a cascade of stronger quakes, which collapsed the Golden Gate Bridge too. The first of many quakes in the made-for-TV flick toppled Seattle's Space Needle. "But if you add in San Francisco and the North Coast, it is literally almost a grade B movie scenario that people don't want to think about that much."Īn NBC miniseries titled "10.5" (as in an off-the-charts magnitude earthquake) actually brought the catastrophic scenario to prime time viewers back in 2004. ![]() In what may be a case where life imitates art - or more precisely, where science catches up to the fertile imaginations of Hollywood script writers - attendees at a major earth science meeting in San Francisco will hear evidence that this cascade of disaster happened many times over the past couple of millennia."I mean, Cascadia is big enough by itself," said lead researcher Chris Goldfinger of Oregon State University. New earthquake research to be presented by Oregon-based geologists next week sounds like a B movie plot - a great earthquake along the Pacific Northwest's offshore Cascadia fault triggers another great earthquake on the northern San Andreas Fault.
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