The Alaskan Earthquake of 1964

By Olivia Jenkins

The 1964 Alaskan earthquake…

…also known as the Great Alaskan Earthquake, the Portage Earthquake and the Good Friday Earthquake, lasted nearly four minutes on Good Friday, March 27,

1964. This megathrust earthquake attacked south-central Alaska and caused ground fissures, collapsing

structures, and tsunamis. It was the most powerful recorded earthquake in U.S. and North American history, at a shocking magnitude

of 9.2, and the second most powerful in the entire world, only to the horrible1960 Valdivia earthquake,

also known as the Great Chilean Earthquake.

Wikipedia states…“The powerful earthquake produced earthquake liquefaction in the region. Ground fissures and failures caused major structural damage in several communities, much damage to property and several landslides. Anchorage (my hometown) sustained great destruction or damage to many inadequately 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. Two hundred miles southwest, some areas near Kodiak were permanently raised by 30 feet (9.1 m). 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.”

Resulting Casualties…

The damage… Most damage occurred in Anchorage, 75 miles northwest of the epicenter. Luckily, Anchorage was not hit by tsunamis. But downtown Anchorage was still severely damaged, and parts of the city built on sandy bluffs overlying "Bootlegger Cove clay" near Cook Inlet, most notably the Turnagain neighborhood, suffered landslide damage. The neighborhood lost a total of 75 houses in the landslide, and the destroyed area has since been turned into Earthquake Park. The Government Hill school was left in two jagged, broken pieces due to a landslide. Land overlooking the Ship Creek valley near the Alaska Railroad yards also slid, destroying many acres of buildings and city blocks in downtown Anchorage. Most other areas of the city were only moderately damaged. The 60-foot concrete control tower at Anchorage International Airport was not engineered to withstand earthquake activity and actually collapsed, killing one employee.

More pictures…

Interesting tidbits…

Valdez, AK was not totally destroyed, but after three years, the town relocated to higher ground 7 km (4 mi) west of its original site

The earthquake caused the Cold-War era ballistic missile detection radar of Clear Air Force Station to go offline for six minutes, the only unscheduled interruption in its operational history

Near Cordova, the Million Dollar Bridge crossing the Copper River also collapsed

Other towns along the U.S. Pacific Northwest and Hawaii were damaged

Minor damage to boats reached as far south as Los Angeles

Several fishing boats were sunk in Louisiana, and water sloshed in wells in Africa

Aftershocks…

There were literally thousands of aftershocks for three weeks, following the major, life-shattering earthquake. On the first day alone, eleven scary aftershocks were recorded with a magnitude greater than 6.2. Nine more ensued over the next three weeks. More than a year later, the aftershocks stopped.

Sources…

https://www.google.com/search?q=1964+alaska+earthquake&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=k5vGULDwF-L9igLX94EI&biw=1280&bih=671&sei=n5vGUMz6MOahiQKK8IHYAg

http://en.wikipedia.org/wiki/1964_Alaska_earthquake http://

www.aeic.alaska.edu/quakes/Alaska_1964_earthquake.html http://

www.anchoragemuseum.org/galleries/alaska_gallery/earthquake.aspx