We often hear geologists talking about the Cascadia Subduction Zone. That’s the deep fault off our coast that could produce the “big one.”
But state geologists point out there are thousands of other faults onshore. Dozens of them are still active.
Just in the Portland area alone, geologists know of at least five faults.
“We’ve had several magnitude five or larger quakes in Portland history,” said Ian Madin with the Oregon Department of Geology and Mineral Industries.
And geologists are finding new faults all the time.
Just two months ago they discovered a 60-mile stretch of previously unknown faults on Mount Hood.
Read more: http://www.kgw.com/story/news/local/green/2015/04/28/at-least-five-faults-could-create-earthquakes-in-portland/26546431/