Alaska’s continental shelf and North American plate rose over 9 meters during the earthquake. This sudden displacement of the ocean floor, along with earthquake-induced landslides, generated massive local tsunamis that resulted in 70 percent of the fatalities in southern Alaska. The tsunamis created by the earthquake reached land within a few minutes of the ground shaking and engulfed some areas as much as 170 feet above sea level. Scientists measured a wave runup of 220 feet in the Valdez Inlet.

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