SEWARD, Alaska -
By Alexis De Leon For Seward City News -
In memoriam of the Great Alaska Earthquake of 1964
It had been a long wait for winter to end, when the sun finally peaked out over the snowed covered mountains, waking up the citizens of Alaska, March 27, 1964. The weekend was well under way as cheerful Alaskans gathered outdoors for Good Friday. Families were coming together to celebrate the arrival of spring and rebirth when tragedy struck at approximately 5:36 p.m.
At first there was only a small ripple, one that went unnoticed by running children and distracted parents, but within seconds the ripple escalated into a literal life- shattering earthquake of magnitude 9.2 (moment magnitude scale).
The epicenter, or origination point, of the earthquake occurred with in the vicinity of Prince William Sound. About 56 miles (90 km) away from the epicenter, the quaint city of Valdez found itself feeling the full force of the earthquake for a devastating four minutes, not to mention the aftershocks that were felt for up to three weeks after the initial earthquake.
According to the Alaska Earthquake Information Center, The Great Alaska Earthquake is still the second largest earthquake world wide ever recorded, second only to the M 9.5 earthquake that rattled Chile only four years prior.
The earthquake not only ravaged Valdez but also severely damaged Seward, Kodiak Island, Anchorage and surrounding areas. In some cases, as with Valdez and Portage, the cities were completely demolished.
Essentially what occurred was this: as the Pacific plate pushed northwest gradually it pressed against the North American plate, which Alaska lies on, forcing the coast of the plate downward creating a subduction zone. After a ridiculous amount of hundreds of years of pressure culminating from years upon years of giant landmasses cramming together finally reached its peak.
After years of surmounting pressure, the subduction zone surrounding Alaska finally relieved itself March 27, 1964 in the most abrupt way. The effect is much like a fishing line with too much tension. Once the line reaches its tension capacity it snaps, releasing the tension and causing the fishing pole to thrash back and forth sending smaller vibrations throughout the entire pole, for quite sometime if the quality is fare.
After the initial earthquake, those who survived felt relieved and unaware of the second plague earthquakes bring: tsunamis. Citizens of Whittier were actually struck by tsunamis before the tremors of the earthquake had ceased (typically unheard of).
The second largest tsunami in world history, second only to the tsunami to follow the 1960 Chilean earthquake, gathered into a heaving mass of sheer power as it raised a reported 70 km or nearly 230 feet above sea level off the coast of the Valdez Arm.
The landslides caused by the earthquake tumbled into the watery depths below in areas such as Valdez and Seward. A landslide in Valdez made light work of crushing the harbor claiming a reported 30 lives in its wake.
Tsunamis, unlike a typical breaking wave, have a far longer wavelength and thus resemble a rising tide, which is why they are often referred to as “tidal waves.” As the plates shift downward they displace massive amounts of seawater. Having no other outlet in which to displace the water tsunamis form as the water builds on top of the subduction zone. Once the plate releases the pressure, the tsunami builds until the wave reaches a maximum carrying capacity at which it then crashes forward much like a far more powerful wave.
In total 131 deaths were recorded due to the earthquake while 119 alone were caused by the tsunamis. Oregon and California also reported four and 12 deaths respectively due to the tsunamis.
The structural damage, or in cases like Valdez, total devastation, cost Alaska more than an estimated 300 million dollars by 1964 economic standards. Today damage consisting of equal value would be around 2.3 billion dollars due to inflation.
“In addition to damage in the epicentral region immediately following the quake, long period seismic waves traveled around the earth for several weeks. Basically the whole earth vibrated (rang) like a church bell during this time. States as far away as Texas and Florida were affected with vertical motions of up to 5 to 10 cm.” Dr. Doug Christensen of the Geophysical Institute wrote in a report titled “The Great Alaska Earthquake of 1964” for the University of Alaska Fairbanks.
Some cities, such as Anchorage, simply rebuilt what the earthquake destroyed. According to the Alaska Gold Traveler’s Guide, the city of Valdez decided to relocate and rebuild in a more sheltered location nearby the original city.
However some areas were beyond repair, such as Portage. Only the ghostly remains of cabin roof tops linger on as reminders, while the rest of the land now provides refuge to several hundred animals at the Alaska Wildlife Conservation Center.
Today Alaska has experienced more than 2600 M 5 and greater earthquakes over the past 50 years. While none have been quite as horrific as the Great Alaska Earthquake of 1964, each as been influential in shaping the way scientists, experts and citizens of Alaska look at and learn about earthquakes.
Several safety precautions have been put into affect since 1964 including: tsunami evacuation routes, weekly siren tests and various drills. Seward will be demonstrating their earthquake/tsunami preparedness come this Wednesday, March 27 with a drill dubbed “Chill, it’s a drill!” Presented by the National Weather Service and Alaska’s Division of Homeland Security and Emergency Management, in cooperation with the Alaska Broadcasters Association.
Mary J. Barry, a woman who experienced the tragedy first hand, states in her novel “A Day of Disaster: The Great Alaska Earthquake of March 27, 1964”
“…I believe that the history of the earthquake and its associated personal experiences is extremely important to preserve, as each year draws further away from the 1964 incident, with fewer people to remember it, and even a tendency for ‘amnesia’ to set in, to disregard future hazards to themselves and their properties.”