![]() Death toll, damage, and casualties The largest landslide in Anchorage occurred along Knik Arm between Point Woronzof and Fish Creek, causing substantial damage to numerous homes in the Turnagain-By-The-Sea subdivision. The largest tsunami wave was recorded in Shoup Bay, Alaska, with a height of about 220 ft (67 m). Tsunami waves were noted in over 20 countries, including Peru, New Zealand, Papua New Guinea, Japan, Mexico, and in the continent of Antarctica. These smaller tsunamis were produced by submarine and subaerial landslides and were responsible for the majority of the tsunami damage. ![]() There was a tectonic tsunami produced in addition to about 20 smaller and local tsunamis. Two types of tsunami were produced by this subduction zone earthquake. The map does not show the height or strength of the waves, only the calculated travel times. Tsunami Travel Times computed using Tsunami Travel Times software v3.1 (P. Tsunami Calculated travel time map for the tectonic tsunami produced by the 1964 Prince William Sound earthquake in Alaska. ![]() This caused much of the uneven ground which is the result of ground shifted to the opposite elevation. The fault responsible was the Aleutian Megathrust, a reverse fault caused by a compressional force. The Alaska earthquake was a subduction zone (megathrust) earthquake, caused by an oceanic plate sinking under a continental plate. Studies of ground motion have led to a peak ground acceleration estimate of 0.14–0.18 g. Vertical displacement of up to 38 feet (12 m) occurred, affecting an area of 100,000 square miles (260,000 km 2) within Alaska. Large rockslides were also caused, resulting in great property damage. Ocean floor shifts created large tsunamis (up to 220 feet (67 m) in height), which resulted in many of the deaths and much of the property damage. The focus occurred at a depth of approximately 15.5 mi (24.9 km). The epicenter of the earthquake was 12.4 mi (20.0 km) north of Prince William Sound, 78 miles (126 km) east of Anchorage and 40 miles (64 km) west of Valdez. UTC), a fault between the Pacific and North American plates ruptured near College Fjord in Prince William Sound. Evidence of motion directly related to the earthquake was also reported from Florida and Texas. Tsunamis also caused damage in Hawaii and Japan. Post-quake tsunamis severely affected Whittier, Seward, Kodiak, and other Alaskan communities, as well as people and property in British Columbia, Washington, Oregon, and California. Nearby, a 27-foot (8.2 m) tsunami destroyed the village of Chenega, killing 23 of the 68 people who lived there survivors out-ran the wave, climbing to high ground. In Prince William Sound, Port Valdez suffered a massive underwater landslide, resulting in the deaths of 32 people between the collapse of the Valdez city harbor and docks, and inside the ship that was docked there at the time. Southeast of Anchorage, areas around the head of Turnagain Arm near Girdwood and Portage dropped as much as 8 feet (2.4 m), requiring reconstruction and fill to raise the Seward Highway above the new high tide mark. ![]() Two hundred miles (320 km) southwest, some areas near Kodiak were permanently raised by 30 feet (9 m). Anchorage sustained great destruction or damage to many inadequately earthquake-engineered houses, buildings, and infrastructure (paved streets, sidewalks, water and sewer mains, electrical systems, and other man-made equipment), particularly in the several landslide zones along Knik Arm. Soil liquefaction, fissures, landslides, and other ground failures caused major structural damage in several communities and much damage to property. Six hundred miles (970 km) of fault ruptured at once and moved up to 60 ft (18 m), releasing about 500 years of stress buildup. Lasting four minutes and thirty-eight seconds, the magnitude 9.2 megathrust earthquake remains the most powerful earthquake ever recorded in North America, and the second most powerful earthquake ever recorded in the world since modern seismography began in 1900. Across south-central Alaska, ground fissures, collapsing structures, and tsunamis resulting from the earthquake caused about 131 deaths. ![]() The 1964 Alaskan earthquake, also known as the Great Alaskan earthquake and Good Friday earthquake, occurred at 5:36 pm AKST on Good Friday, March 27. Run-up of 67 m (220 ft) at Shoup Bay, Alaska. ![]()
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