A 9.2-magnitude earthquake, struck South-central Alaska on March 27, 1964. It is the strongest earthquake in U.S. history and second-most powerful worldwide The quake lasted 4.5 minutes, causing 139 fatalities, devastating tsunamis and major structural damage.
The epicenter was in the northern Prince William Sound region, roughly 75 miles east of Anchorage. The rupture spanned 800 km (500 miles) of the Earth's crust, with the Pacific plate breaking free from the North America. The event caused massive vertical changes, some areas, like Kodiak and Hinchinbrook Island, were permanently raised by up to 30 feet, while other areas dropped up to 8 feet. Resulting tsunamis affected the coasts of Alaska, British Columbia, and Northern California. The city of Valdez experienced a massive underwater landslide, and in Anchorage, 4th Avenue dropped 3 meters. The disaster led to major improvements in scientific understanding, prompting the development of the NOAA Tsunami Warning Centers and the USGS Earthquake Hazards Program. More
