For better and worse, the North Coast is in earthquake country. While shifting tectonic plates define the epic contours of Humboldt's landscape, their seismological side effects pose a major threat to life and infrastructure. "We do live in earthquake country," says Jay Patton of the California Geological Survey. "And the really cool thing is that a little bit of knowledge goes a long ways in terms of helping yourself be more safe and resilient."
On this episode, Patton talks about local tsunami maps, early-warning technologies, and what people living on shaky ground can do to be prepared.
Transcript:
Tom Jackson: I'm Tom Jackson, President of Cal Poly Humboldt, and I'm here today. Join with my dear friend and colleague, Dr. Keith Flamer from the College of Redwoods. Good to see you, Keith.
Keith Flamer: Good to see you, Tom. Always a pleasure.
Tom Jackson: Oftentimes, we wonder why the house is shaking. And we're here today with Jay Patton, who is all things earthquakes, tsunamis and other Godzilla moments. Jay, let's just jump right into it. How did you get into this and why?
Jay Patton: Well, I was attending classes at Humboldt State and I was an anthropology student and taking archeology classes. And my archeology teacher suggested I take a class called Earthquake Country, and I immediately added a whole bunch of geology classes. That was the beginning of it all. Earthquake country.
Tom Jackson: We live in earthquake country. What should we know about this?
Jay Patton: We do live in earthquake country. And the really cool thing is that a little bit of knowledge goes a long ways in terms of helping yourself be more safe and resilient. There is a publication is called Living on Shaky Ground, and this brochure, which is also available online, has all the information that anyone needs to know to learn about how to prepare their house, what to do during an earthquake, what to do during a tsunami.
So I encourage people to go online and do an Internet search for 'living on shaky ground'. Just start learning what you can do. Do you know what to do during an earthquake?
Keith Flamer: Get under a table. Get in the bathtub. What does one do?
Jay Patton That's right! Drop, cover and hold on. If you're in bed during the earthquake, stay in bed, it’s the safest place to be. Because once you start walking around, things that might fall off the shelves might hit you. So it's really good just to stay in bed.
When that earthquake happens and causes the tsunami… what we do first, we feel the earthquake, so we drop, cover and hold on. And then if we're at the coast, what we want to do is we want to as soon as we can, walk to high ground.
Tom Jackson: How high up do you have to be to avoid a tsunami along the north coast?
Jay Patton: So we have maps and these maps show where we think a tsunami might happen. People ask, ‘What is the elevation that those maps are based on?’ And the answer is that they're not really based on an elevation. If you think about when you're in a bathtub and you're splish-splashing the water, sometimes the water goes higher in some places of the tub and not as high in other places.
Well, tsunamis are just like that, because there are things that slow the tsunamis down. So I live in Manila, and if I go out to the beach, the tsunami there is going to be larger in size than the same tsunami after it comes into the bay and comes up to the Arcata marsh. And that's because the mouth of the bay and the channels, they slow the tsunami down.
They absorb some of the energy. One of the best things that someone could do is look for these tsunami hazard area maps and brochures.
Keith Flamer: Okay. So, Jay, I watched a movie recently; it's sci-fi and there was a scientist that said that he could predict where an earthquake would hit and when.
Jay Patton: Well, the keyword that you use right there…
Keith Flamer: Sci-fi…
Jay Patton: ..Is science fiction. So that is the goal. It's not really something that's true - yet.
Tom Jackson: In the news today, and certainly in the research, is the overlay of technology on fiberoptic to help predict earthquakes. How fast will it be before we actually get to use it?
Jay Patton: That's a great question, because that's cutting-edge science. In recent years, we've learned that we can use fiber optic cable basically as a seismometer. There is a cable running from Arcata to Eureka that we've been using as an experiment. It's sort of like 7000 seismometers along that cable. We've already been making some discoveries, but we're testing it so that we could use an offshore cable to incorporate into the earthquake early warning system.
That's important because it's closer to the earthquake. And so it could get our information sooner than the seismometers that are on shore.
Tom Jackson: We're here with Jay Patton, earthquake and tsunami expert. How do we speed that up?
Jay Patton: So there are several things that need to take place to turn that into a reality. One is the science hasn't really gotten fully fleshed out, so that's going to take several years. And then the other part of it is that we need to raise the money to ask those companies who are installing those cables, ‘we want to add one more fiber cable to your main cable, and we will pay for it.’
And that way we can install a cable that will be dedicated for this purpose.
Keith Flamer: How prepared are we, number one, and two, when will 'The Big One' that I've heard about since I moved to California - when will that come? And I know we can't predict, but what is your best guess? What should we expect?
Jay Patton: Well, we're more prepared than we think we are, but we also have a lot more preparation to do. One of the things that everyone should have when they live in earthquake country is a ‘go bag’. It’s a backpack that has some survival supplies, food, water, medicines.
And so the question about ‘when is the next big thing going to happen?’ Like you said, you know, we can't predict and we never know when the next one is going to happen. And all we can do is we can look at the past. What's the chance that it might happen over a certain span of time?
Keith Flamer: Can you also talk about how do we define ‘The Big One’? Because what does it mean to have to live here? The big.
Jay Patton: One? There are two main fault systems that people talk about 'The Big One' in California. One is the San Andreas Fault, and that runs from Southern California along the Salton Sea, all the way to just northeast of Petrolia. And then the Cascadia Subduction Zone is the other one that can cause 'The Big One'. A ‘Big One’ on the San Andreas Fault, something like a 7.5 to maybe a magnitude eight earthquake in the Cascadia Subduction Zone.
That would be a maybe a magnitude 8.5 to a 9.2. So those are 'The Big Ones’. The last San Andreas Fault earthquake, that was in 1906. And so it looks like that those happen about every 300 years or so. And then in Cascadia, in northern California, they happen about every 220 to 240 years. And in Washington, they happen about every 480 years.
So the last Cascadia subduction zone earthquake was in January of 1700. So it was over. It was longer than the average. So there is a good chance that it might happen during our lifetimes, but we'll just never know. So that's why we just all need to be earthquake safe and learn what to do during an earthquake. And you all know what to do: Drop, cover and hold on!
Keith Flamer: …And have a go bag.
Tom Jackson: Jay Patton, thank you very much for your insights today. It's very informative. Again, thank you.
Keith Flamer: Thank you!
Jay Patton: Thanks for having me.
