I read "Cascadia's Fault" about ten years ago. It was then updated after the Japan subduction zone quake so I, of course, had to re read it.

Don't read this book if you want to get a good nights sleep!

Think of the west coast as a crumpled piece of carpet. Since the 1700 event the Olympic mountains have risen 10 feet up and 8 feet over Puget Sound while Puget Sound has been pushed down ~8 feet. So when Cascadia rips the coast will drop 10 feet and PS will rise 8 feet frown . If it is a complete failure the shaking will last up to six minutes (or more) as the fault breaks from the north tip of Vancouver Island to Crescent City Ca.

I'm with Sky-Guy. Since 1966 there have been two subduction quakes in Ak, two off of Chile and one off of Japan so I can't see how the Cascadia zone isn't over due.
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