It was known as the great Alaska earthquake. On March 27, 1964, an earthquake with a magnitude of 9.2 struck the Prince William Sound region of Alaska. This earthquake is the second largest earthquake ever recorded in the world, the first as a magnitude 9.2 in Chile in 1960. In other words, this earthquake released 10 million times more energy than the atomic bomb dropped on Hiroshima Japan. Equally important, this (Abby Lautt) earthquake produced landslides and caused catastrophic damage covering an area of 130,000 square kilometers, which is the entire state of Alaska, parts of Canada and Washington. The earthquake lasted approximately four minutes with eleven substantial after shock occurring over the next 24hrs causing damages in the amount of almost $400,000 and killed 131 people.
The epicenter of the earthquake in Alaska was about 10km east of the College Fiord, approximately 90km west of Valdez and 120km east of Anchorage, Alaska largest city. The earthquake was felt about 1,300,000 square kilometers away from the epicenter. (Christensen, Doug PhD.) About 30 kilometers deep, the first slip occurred under northern Prince William Sound, and an 800 kilometer rupture in the rocks extended horizontally, roughly parallel to the Aleutian trench. (Bolt) The cause of this massive earthquake was the vertical displacement of northwest motion of the Pacific plate. Also, it was estimated that about 200,000 square kilometers of the crust were deformed, making this the greatest area of vertical displacement ever measured. (Bolt)
Additionally, this earthquake occurred on a thrust fault. This fault was a subduction zone slip which occurred primarily beneath the ocean were the Pacific plate plunges underneath the North American plate. This sudden upward movement of the sea floor along the rupturing fault generated a massive tsunami. This vertical deformation affected an area of about 250,000 km2 and the resulting movement of the Pacific plate under the North American plate was about 9 meters. (Christensen, Doug PhD.) (Stover) (Bolt)
Following the 9.2 magnitude earthquake, the aftershock zone was about 250 km wide and extended from Prince William Sound to the southwestern end to Kodiak Island, which is a distance of 800 km. The Pacific and North American plate boundary where where the mainshock and its aftershocks occurred. In addition, there were 11 aftershocks with a magnitude of 6.0 and higher recorded in the first 24 hours following the earthquake
In view of this massive earthquake, the damage to buildings in southern Alaska varied considerably, depending on the foundation and the type of structure. Farther away from the epicenter in Anchorage, were most of the property damage occurred , the buildings that were affected the most were the higher ones due to mainly the long waves, whereas, framed houses were reasonably unscathed. The J.C. Penney's building facade consisted of massive concrete panels, which were five inches thick....