The state also experienced the second-largest earthquake to ever hit the US - - a 9. Friday's 7. The area is marked by subduction zones, where two of the Earth's tectonic plates meet, according to Randy Baldwin, a geophysicist with the US Geological Survey. These quakes occur as a result of stresses caused by movements of tectonic plates that make up the Earth's outer shell.
In this region, the Pacific Plate moves steadily northward at a rate of about 2 inches per year and descends, or "subducts," beneath the North American Plate. An irregularity on top of the Pacific Plate, known as the Yakutat block YAK , impedes smooth subduction of the Pacific Plate and has caused a wedged-shaped piece of the North American Plate, the Wrangell Subplate, to break loose and rotate counterclockwise.
Probabilistic ground-acceleration map for Alaska. Colors depict the peak acceleration that has a 10 percent probability of being exceeded in a year period. Next teleconference: Thursday, Nov 18, , PM - PM Call-in: , Code: For meeting notices and other public announcements, subscribe to our listserv.
The M8. State of Alaska. Alaska Seismic Hazards Safety Commission. All recorded earthquakes in Alaska from to the present. These two plates form a subduction zone where the latter plate is being constantly forced under the former, creating an intense amount of friction that causes earthquakes when released. The earthquake that struck Alaska is still remembered as one of the most devastating in history. The 9. It was the second largest quake ever recorded in the world.
National Geographic covered the devastation in The full feature is behind our paywall.
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