Alaska's Good Friday earthquake in shocking images, 1964

On March 27, 1964, at 5:36 p.m., a megathrust earthquake struck the Prince William Sound region of Alaska. The epicenter of the earthquake was about 10 km east of the mouth of College Fiord, about 90 km west of Valdez and 120 km east of Anchorage.

Lasting four minutes and thirty-eight seconds, the magnitude 9.2 earthquake is the most powerful earthquake ever recorded in North American history, and the second most powerful earthquake ever recorded in world history.

Eyewitnesses reported that as the earth was shaking, a hoarse, grinding sound was heard. He remembered that asphalt roads rise and fall like waves and the ground opens and closes in front of them, water rises up through the cracks that follow.

Violent aftershocks broke water, sewer and gas lines and caused widespread telephone and power failures. It easily toppled telephone poles, broke railroad tracks, cut roads in half, uprooted buildings, cars and docks, and broke homes. The seismic waves caused the Earth to "ring like a bell".

The initial earthquake and subsequent underwater landslides caused several tsunamis, which caused heavy damage to the coastal cities of Valdez, Whittier, Seward and Kodiak. The city of Valdez was originally built on sand and gravel.

When the earthquake occurred, the seismic waves caused the liquefaction of the soil and a part of the delta slipped into Port Valdez, taking most of the port's resources, living and otherwise, with it.

The Delta meltdown triggered a local tsunami that destroyed almost everything that was left and caused Union Oil Company's oil tanks to explode, causing a massive fire.

While Valdez was originally leveled, Anchorage caused many insufficient earthquake-engineered homes, buildings and infrastructure (paved roads, sidewalks, water and sewer mains, electrical systems and other man-made equipment) to be greatly affected, especially in many landslides. sustained destruction or damage. Area with Nike Arm.

As a result of the quake, 131 people are believed to have died: nine people died as a result of the quake, 122 died from the subsequent tsunami in locations around the world, five died from the tsunami in Oregon, and 13 died. Tsunami in California.

The earthquake was a reported XI on the modified Mercalli intensity scale "indicating major structural damage, and ground cracks and failures". Property damage was estimated at approximately $116 million ($0.73 billion in 2018 dollars). It is likely that if the earthquake had not occurred after 5 pm on Good Friday, the death toll would have been much higher.

Geological surveys carried out shortly thereafter showed that some parts of the Alaskan coast were submerged by eight feet (2.5 m), others rose to 38 feet (11.5 m) and that most of the coast was 50 feet (15 m) above sea level. have progressed. Coastal forests fell below sea level and were destroyed by salt water.

Before the 1964 Alaska earthquake, scientists had limited knowledge of what happens beneath the Earth. Later, geologists realized subduction zones—the areas where two tectonic plates (huge slabs of rock made up of the Earth's crust and upper mantle) meet and subduct under each other—played a major role in creating the giant Alaska earthquake. played.

Scientists learned that the point at which the North American Plate crossed the Pacific Plate descended into a subduction zone. According to the United States Geological Survey, "The 1964 earthquake was enormous due to the large area of ​​fault slip during the earthquake and the large amount of slip, or relative motion, between opposite sides of the earthquake fault.