Pointing out faults is a good thing when it comes to earthquake warnings. And scientists at Idaho State University recently did that by mapping a large seismic fault in in the Rocky Mountains with the potential to cause a magnitude-7.5 earthquake.
The 40-mile-long fracture in the earth's crust was found at the base of the Sawtooth mountains in central Idaho. The 100 year-round residents of Stanley, Idaho, would likely feel the most intense shaking. But moderate shaking could extend from Sun Valley, Idaho, a resort community, to Boise, Idaho's capital.
Residents of Stanley and other nearby towns would be prudent to earthquake-proof their homes, said Glenn Thackray, chairman of Idaho State University geo-sciences department in an interview with Reuters. But…
"Predicting when a fault might rupture is a real uncertainty of science. The problems with earthquakes and faults are they don't follow reliable patterns,” Thackray said.
"There's a chance in the next few decades there will be an earthquake on this fault — and if it does happen it will be a rather large earthquake," he said.
Thackray and the other researchers observed the history of the faultline in the sediments of Redfish Lake. They found that the fault triggered quakes in the area 7,000 and 4,000 years ago. This suggests that quakes may occur every several thousand years.
Photo credit: Casey Kellogg/Montana DNRC