The Pacific Northwest is due for a Major Earthquake

- The Pacific Northwest is due for a major earthquake. - These really dramatic events have happened in our past and they will happen again. - Tony Johnson is Chairman of the Chinook Indian Nation, one of the Indigenous communities already preparing for the next "Big One." - You know, we spent a lot of time worrying about what's that going to look like? It's a really grave concern for us. - We really need to be prepared for that eventuality because it's not a matter of if, it's just a matter of when. (dramatic music) - These days, it may seem like earthquakes are not all that uncommon due to frequent media reports... - Breaking news just into CNN, a very strong earthquake just minutes ago... - And lots of cell phone videos posted online. But it's actually been centuries since the contiguous U.S. last experienced a truly "Big One," an earthquake with a magnitude greater than eight. The last one on record was the earthquake of 1700 with an estimated magnitude of nine. So, what caused this earthquake? - The biggest earthquakes in the world are along subduction zone boundaries. And those are places where one tectonic plate is diving down underneath another tectonic plate. The largest earthquake that's happened in the U.S. that we're aware of was along the Cascadia Subduction Zone where the Juan de Fuca Plate is diving down underneath the North American Plate. And we can get really big earthquakes there because the plate that's going down is usually oceanic crust, which is cold and dense, that means it can break. So if you think about baking chocolate chip cookies, when you pull the cookies right out of the oven, they bend and they're nice and gooey, but once they've gotten to be cold, they break. So that cold dense crust that's going down can break for a much longer time. So we get bigger earthquakes in those particular places. - The same tectonic activity that caused the earthquakes resulted in another destructive event-- a tsunami. - You have one plate diving down beneath another. This section gets locked and it pushes this part up. When the fault ruptures, when the amount of stress overcomes the friction, it bounces back, which lifts up the water above it and causes that water to flow out in all directions. And that water flowing out in all directions is the tsunami. - Clues about the earthquake and tsunami of 1700 can be found in these eerie looking ghost forests. - And we have evidence of these submerged trees or the ghost forests in numerous places around our area, including at our traditional village. - These ghost forests formed when the area became submerged after being hit by the tsunami. Even after the tsunami receded, the entire landscape had actually dropped several feet, a result of the plate tectonic motion. Oral histories of the event suggest that many died in the tsunami. And Heritage and Cultural Director of the Shoalwater Bay Tribe, Earl Davis, explains how additional clues about life after this earthquake and tsunami were pieced together. - The archaeological record basically suggests that tsunami came, laid down a bunch of sand, and then people went back to kind of normal life. You can see it right in the soil. There's a layer of just sterile sand and then there's an occupation layer immediately after it. It doesn't appear like there was a huge rebuilding time for us back then. - For communities along the coast at sea level, an earthquake and tsunami event could have a much bigger impact today than it did in 1700. - Our lifestyle now is largely predicated on the modern Western colonialized-type lifestyle of putting in a cement foundation and running all these utilities and building a big, expensive infrastructure that is supposed to be there for 200 or 300 years. Whereas traditionally speaking, we put some poles in the ground, covered them in planks, lived there for half the year, then packed up all the planks and went to where we had another house, maybe up to 100 miles away to better fishing grounds or better grounds for avoiding harsher weather. - And the threat of another event like this is very real. - The geologic record tells us that there are large earthquakes along that boundary about every 300 to 500 years. - Which means we could be getting close to another "Big One" The Shoalwater Bay Tribe applied for and received federal funding to construct a tsunami evacuation tower on their reservation, a structure that could protect the most vulnerable populations by providing quick access to higher ground. - The driving force behind the tsunami tower is giving a place down there a fighting chance of getting up above that wave. - When completed, the tsunami tower will be only the second in the country. However, other Indigenous communities that the U.S. government has failed to recognize don't have access to the same federal resources, like the Chinook Indian Nation that Tony Johnson's a member of. - We have the great benefit of continuing to reside on our Aboriginal lands and we have the horrible reality of not being truly federally recognized as an Indian community. And with that federal recognition comes so much of the support that we need. You know, we have a goal or at least an initial thought of building two tsunami evacuation towers, but don't have access to the resources that our federally recognized neighbors have. I don't think it is very likely that anybody will leave the village after a nine point earthquake. There's a bridge to the landform that most folks live on and I can't imagine that bridge surviving that earthquake. So it really will be that folks on the island itself are going to either be high enough or not. (somber music)

Channel: NOVA PBS Official

Views: 1,808,331

Rating: 4.794333 out of 5

Keywords: Earthquake, Earthquakes, Magnitude, Magnitude 8.0, Magnitude 8, Magnitude 9.0, Magnitude 9, Pacific, Pacific Northwest, Shoalwater Bay, Shoalwater Bay Tribe, Shoal Water Bay, Shoal Water Bay Tribe, Chinook, Chinook Nation, Chinook Indian, Chinook Indian Nation, Indian Country, Native American, Native Indian, Native peoples, Native people, Indigenous, Tsunami, Natural disaster, seismic, seismology, subduction, subduction zone, fault line, faults, seismic activity, tectonic plates, NOVA

Id: dZ13TZk5eH4

Length: 6min 12sec (372 seconds)

Published: Wed Jun 30 2021

Reddit Comments

[u/NetWeaselSC]

Is this the same kind of "due for" that Yellowstone is "due for"?

[u/Sdl5]

It's been due for hundreds of years.

Now ask WHY all the offshore feeds on the Juan de Fuca were shut off, and the PNW tremor reporting regularly shows zero, and somehow OREGON NEVER HAS QUAKES per the USGS, and any attempt to discuss this risk or issues are attacked and blocked and pooh-poohed- outside a pretty packaged annual msm film like this at least...

[u/Centaurea16]

The response here will be worse than it was with Katrina. I'm saying that as a Katrina survivor who now lives in the Pacific NW. They are woefully unprepared here. They don't have a clue what the probable result of a major earthquake would be, much less what's involved in recovering from a large-scale natural disaster.

Even if they did have a clue, the neoliberal PNW is so hogtied by its inefficient bureaucracy, they wouldn't be able to handle a significant natural disaster.

So far, the extent of preparations here have been advising the public to keep a 2-week emergency bag ready. Two weeks. 😐 This is some big-time denial. Try at least six months, at a minimum.

Some government official in Portland was saying they're trying to figure out how to keep people going to their jobs as normally as possible in the immediate aftermath of a major earthquake.

I shook my head when I read that. They seriously do not have a clue. They are not prepared. They don't seem to understand what an infrastructure collapse looks like. And they seem to have no comprehension of what going through a traumatic event involves, on both the individual and community levels.

And that's on a local and state level. I don't think the feds would do any better. Bush's horrible performance after Katrina in 2005 marked the beginning of the end of his popularity. Unfortunately, in the interim the American people have gotten used to that low level of performance from their "leaders".

[u/RandomCollection]

Does anyone else think that when the "big one" happens along the West Coast (and everyone knows that it will happen eventually), will the response be worse than Hurricane Katrina was?

Geologists have been saying the West Coast of the US is overdue for a big one for decades now. It will happen eventually.