A good portion of Alaska’s population, or at least those younger than 50 years old, were spared the experience of the “Good Friday Earthquake” in 1964. Those that did ride out the quake experienced a tectonic event that forever changed the way that earthquakes are studied and tracked. And those keeping track of the numbers say the next big earthquake in Alaska isn’t a matter of “if,” but “when.”
Geologist Cindi Preller is one of the people tracking the numbers, and she took the time to kindly, gently terrify the audience of the latest Anchorage Science Pub at The Taproot. Preller is the Tsunami Program Manager for the Alaska region of the National Oceanic and Atmospheric Administration (NOAA). She works with the team at the Alaska Earthquake Information Center (AEIC) in Palmer, and was sure to plug the regular tours offered on Fridays. Preller explained that she works with a group from a variety of backgrounds, because “you can not get a degree in “tsunami,” so we are a combination of geologists, geophysicists, oceanographers…we even have an astrophysicist. I’m not sure why.”
The team at the AEIC is responsible for monitoring seismic activity for the entire north american continent. A Hawaii station monitors activity in the American holdings in the pacific, while Japan has it’s own monitoring center. Preller was quick to emphasize that the Japanese center was the best in the world, “without a doubt,” then offhandedly added, “although, we’re faster.” These monitoring stations must work together with others built in strategic places around the world, creating a network to convey warnings in a timely manner. There was no such system in place in 1964.
Preller used model after model to show the different seismic activity that amounted to the total devastation of the Good Friday Earthquake. Seven separate landslides around Seward poured dirt and clay into what Preller called “the bathtub” of Resurrection Bay. Anchorage was hit particularly hard because it sits on a thick bed of clay. This clay essentially liquefied during the earthquake, causing land and buildings to slide right into the Cook Inlet.
While pictures and written accounts go far to convey the damage and trauma of the Good Friday Earthquake, it was the recorded interviews with survivors that truly resonated.
Studies of the Good Friday Earthquake led to acceptance of the plate tectonics theory. New stations were built to study and create better warning systems for earthquakes. But the timing of earthquakes and the timing of scientific funding don’t always coincide. Preller summed it up:
“We went to all the trouble of assembling scientists and facilities and then it’s flippin’ quiet for 40 years, until Indonesia. Since then, we’ve had more earthquakes than we know what to do with.”
Now: the sobering future.
The Cascadia Subduction Zone extends from California to Vancouver Island, extending just far enough north to cause Alaska some real trouble. Fortunately, the last big earthquake in that particular zone, also known as “The Cascadia Event” was in 1700. Unfortunately, the recurrence interval for the Cascadia Subduction Zone is 400 years. Give or take 100 years. Which means it could “wake up” any day. The real damage from the Cascadia Event was from the resulting tsunamis that hit Japan, drowning hundreds. This is why the event is also known as the Orphan Tsunami.
Preller voiced concern that areas most likely to be effected by an earthquake in this subduction zone, areas like Seattle, WA, Portland, OR, and Vancouver, B.C., haven’t taken what she believes to be adequate precautions in the likelihood of another big event. She said, “it’s almost like they have their heads in the sand.” While this wouldn’t necessarily affect Alaska in terms of violent shakes or tsunamis, our state would still have to deal with other related challenges. Preller referred to the experience in Alaska when the 9/11 terrorist attacks led to all flights being grounded:
“We learned that oranges don’t grow at Fred Meyers [sic]. So we wouldn’t have the communications. We would lose our fiberoptics. We would lose our shipping. I mean, if we take Seattle and Tacoma down, they are really the infrastructure that supports Alaska. We would be affected, greatly.”
If the 1964 Good Friday Earthquake had not been so devastating and far-reaching, it’s possible that scientists might have taken longer to fully grasp the effects of plate tectonics and to begin to eventually build a warning system. This system may not be able to predict when quakes will happen, but it does serve to warn people when they might otherwise not realize the danger until it’s too late. In the meantime, Preller and the team at the AEIC will wait and watch.