A major earthquake off the North Coast resulting in tsunamis can happen at any time: today, tomorrow or two hundred years from now.
With a quake as strong as the one in the Indian Ocean in December 2004, tsunami waves will begin to hit the North Coast before the ground stops shaking. Tsunami waves travel at upwards of 500 mph in the open sea, and reach shore at 40 mph with 40 foot waves or higher.
People right on the coast at that time should head on foot to higher ground immediately. A height of 100 feet should be safe.
Most of Eureka and a lot of Arcata won't be inundated, but travel between them, and between Arcata and McKinleyville, will probably be impossible for an indeterminate time.
A magnitude 9 earthquake off the North Coast will be felt up the coast to Canada and down to southern California, resulting in damage in San Francisco and Sacramento.
For more information on earthquakes, maps on areas of concern and especially on preparing to survive earthquakes and tsunamis, check links through the Humboldt State University geology department page. Here's a link to get started:
Soul of the Future: Realists of the Fantastic - “The oldest, most widespread stories in the world are adventure stories about human heroes who venture into the myth-countries at the risk of their lives, ...
3 days ago