But what does that faraway (e.g. Japanese) earthquake mean for me, in the Pacific Northwest?

Every time an earthquake, somewhere, is big enough to dominate headlines, everyone here in this northwestern corner of the United States starts wondering what it means for us.

Travel times map for Honshu quake

Warning map from NOAA National Tsunami Warning Ctr, for a tsunami generated by the March 11, 2011, Honshu earthquake (yellow star is the epicenter, with the Americas to the right).

This has happened frequently enough (e.g. Haiti, Chile, New Zealand) that I’m thinking it would be useful to create a basic FAQ for earthquakes. Lots of FAQ’s exist, written by scientists, or emergency preparedness teams. But I haven’t come across one that’s written with the fears and fascinations of the public in mind. I guess I’d start with a basic fact:

Not all earthquakes are of the same kind.

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