One thing that causes panic is that the full Cascades quake, 10% in 50 years, will be 9.0. But Portland and Seattle are a long ways from the offshore fault. My

One thing that causes panic is that the full Cascades quake, 10% in 50 years, will be 9.0. But Portland and Seattle are a long ways from the offshore fault. My understanding is that the shaking will feel like M7 but going on for minutes. It will cause lots of damage, especially since there are unreinforced masonry buildings and old infrastructure. But it won’t flatten things like nearby M9. The other is that the more probable quake, 37% in 50 years, is the M8 one on southern section. That will be even less shaking in big cities, but southern Oregon and Northern California will get wrecked. OTOH, the coast will be smashed. They are closer to fault. And then few minutes later will get hit by tsunami. The quake will be similar to the 2011 Japan one. But US is much less prepared. PNW cities could be like Tokyo and ride out quake with little damage.