Tag Archive | Tsunami

January 26, 1700

The Great Quake

January 26, 2021

Thunderbird and Whale battling

 “There was a great storm and hail and flashes of lightning in the darkened, blackened sky, and a great and crashing ‘thunder-noise’ everywhere. Here were also a shaking, jumping up and trembling of the earth beneath, and a rolling up of the great waters.”

So the oral story of the Hoh people had been told, passed down from generation to generation. The event, it turns out, was not the stuff of fiction but can be pinpointed to the night of January 26, 1700.

It was at that moment, triggered by a sudden unlocking of the Juan de Fuca and North American geologic plates, that a estimated 9.2 earthquake shook the west coast from Northern California to Southern British Columbia.

The earthquake triggered a huge tsumani which inundated the coast, wiping out entire villages of people, submerging land, and killing forests.

And then? And then only the oral stories remained and were passed down. But when new people arrived nothing was known of this history until the 1970’s when geologists started piecing together the geologic history.

From the Infallible Wikipedia:

“The earthquake took place at about 21:00 Pacific Time on January 26, 1700 (NS). Although there are no written records for the region from the time, the timing of the earthquake has been inferred from Japanese records of a tsunami that does not correlate with any other Pacific Rim quake. The Japanese records exist primarily in the modern-day Iwate Prefecture, in communities such as Tsugaruishi, Kuwagasaki and Ōtsuchi.

The most important clue linking the tsunami in Japan and the earthquake in the Pacific Northwest comes from studies of tree rings (dendrochronology), which show that several ‘ghost forests’ of red cedar trees in Oregon and Washington, killed by lowering of coastal forests into the tidal zone by the earthquake, have outermost growth rings that formed in 1699, the last growing season before the tsunami. (snip)

Local Native American and First Nations groups residing in Cascadia used oral tradition to transmit knowledge from one generation to the next, so there is no written documentation like that of the Japanese tsunami. However, numerous oral traditions describing a great earthquake and tsunami-like flooding exist among indigenous coastal peoples from British Columbia to Northern California. These do not specify an exact date, and not all earthquake stories in the region can be definitively isolated as referring to the 1700 quake in particular; however, virtually all of the native peoples in the region have at least one traditional story of an event much stronger and more destructive than any other that their community had ever experienced.”

This forensic information, combined with the Japanese records, have made it possible to pinpoint the date and time of the great event.

Ground Zero seems to be located at the mouth of the Copalis River, just north of Gray’s Harbor in Washington State. The ghost forest appears at low tide. It’s been determined that the ground dropped over 6 feet and that the trees all died as a result of a singular event. Through carbon dating and evaluation scientists now know that the event occurred in either late 1699 or early 1700.

But it wasn’t just a onetime thing. Scientists have also found evidence that over 40 megathrust quakes have shaken the PNW in the past 10,000 years. That, it turns out, means an average of 430 years between the quakes. The three most recent events occurred in 810, 1310, and 1700. It’s now been 321 years since the 1700 event. Scientists predict that there is a 37 percent chance of an 8.2 or greater quake in the next 50 years.

Ghost forest on the Copalis River near Gray’s Harbor

For those of us who have lived our entire lives in the PNW, we know exactly where we were and what we were doing on two specific dates in the last 50 years: April 29, 1965 and February 28, 2001.

Those were the dates of the most significant ‘recent’ earthquakes in the region. I was seven years old for the first one and, prior to that April morning, had never heard the term earthquake or understood what it was.

I was standing at the counter in our family bathroom (we had one bathroom for six people!) and my mother was fixing my hair for school. We lived in Yakima, 150 miles from the quake’s epicenter. When the house started to shake my mother, so very calmly, said to me, “It’s an earthquake,” and instructed me to hang on to the counter. Soon that event was forgotten but everyone of my age or older knows where they were at that exact moment, especially people who lived in the Puget Sound area.

Fast forward to February 28, 2001. It’s just before 11 a.m. The kids are at school and I have spent the morning volunteering with my fifth grade son’s class. Around 10:30 – when two other parents arrive – I take off as I have errands to run in advance of the Boy Scouts Blue and Gold banquet scheduled for March 2nd.

When I arrive back at our house on the hill above East Lake Sammamish parkway, my in-laws are there as they have been staying with us for a few days. I tell them that I’m going to have something to eat then go do my errands. I walk to the fridge and open the door. There’s a significant jolt. I shut the fridge door and look up and say “Did you…” to my father-in-law who is standing a few feet away. But I never finish the sentence. By then the entire house is shaking. So I do what my plan has always been in the event of an earthquake. I hurry to our built in desk, move the chair out of the way, and crawl under.

When I turn to look out I see two things: first is my mother-in-law who is sitting on the couch and looks as if she’s bouncing in a boat on choppy water; the second thing I see are my father-in-laws legs getting bigger and bigger until the legs and him attempt to crawl under the desk with me. Trust me, it was not a big desk and that plan did not work. Instead, he ended up crouched next to me until the worst of the shaking stopped after about a minute.

I emerge and look out the back windows; trees are still vibrating and shaking despite the quake being over. Of all the memories of that day, I can still see those trees vibrating. Then I walk around the house to see what’s been damaged. Room after room nothing seems to have fallen… that is until I get to the living room. The painting which hung over the fireplace has slid off the wall and come straight down onto the mantle. There it rests, still intact and literally resting behind a decorative glass piece which, by rights, should have been a casualty of the event.

Later that evening I have the assembled family stage a photo to commemorate that day and soon that quake is also forgotten.

Nothing in the china cabinet was damaged in the 2001 Nisqually quake

It’s on days such as today, however, that I am reminded that the ‘big’ one could strike today, tomorrow, next week, next year, or longer. It really is just a matter of time.

Many links for all my fellow science nerds:

https://en.wikipedia.org/wiki/1700_Cascadia_earthquake

https://www.amnh.org/explore/videos/earth-and-climate/tsunami-science-reducing-the-risk/ghosts-of-tsunamis-past

https://slate.com/technology/2015/09/earthquakes-and-tsunamis-in-the-pacific-northwest-native-american-myths-and-geoscience.html

https://www.atlasobscura.com/articles/pacific-northwest-prepares-for-massive-earthquake

https://en.wikipedia.org/wiki/1965_Puget_Sound_earthquake

https://en.wikipedia.org/wiki/2001_Nisqually_earthquake

Here’s the list of Great Quakes from the Infallible Wikipedia:

1May 22, 1960Valdivia, Chile1960 Valdivia earthquake9.4–9.6
2March 27, 1964Prince William SoundAlaska, United States1964 Alaska earthquake9.2
3December 26, 2004Indian Ocean, Sumatra, Indonesia2004 Indian Ocean earthquake9.1–9.3
4March 11, 2011Pacific Ocean, Tōhoku region, Japan2011 Tōhoku earthquake9.1[3]
5July 8, 1730Valparaiso, Chile (then part of the Spanish Empire)1730 Valparaiso earthquake9.1–9.3 (est.)[4]
6November 4, 1952KamchatkaRussian SFSRSoviet Union1952 Kamchatka earthquakes9.0[5]
7August 13, 1868Arica, Chile (then Peru)1868 Arica earthquake8.5–9.0 (est.)
8January 26, 1700Pacific Ocean, US and Canada (then claimed by the Spanish Empire and the British Empire)1700 Cascadia earthquake8.7–9.2 (est.)
9April 2, 1762ChittagongBangladesh (then Kingdom of Mrauk U)1762 Arakan earthquake8.8 (est.)
10November 25, 1833Sumatra, Indonesia (then part of the Dutch East Indies)1833 Sumatra earthquake8.8 (est.)

Tsunami!

December 26, 2017

TsunamifloodBigI admit it. I’m a complete nerd when it comes to natural disasters. I’m fascinated by tornadoes and all nature related phenomenon. And while we are mostly able to deal with windstorms, snowstorms and the occasional earthquake here in the Pacific Northwest, it’s impossible to imagine what December 26, 2004 must have been like for the people who experienced a rare mega-thrust earthquake and the devastating tsunami which struck near Sumatra in the Indian Ocean.

According to the infallible Wikipedia:

“It is the third-largest earthquake ever recorded on a seismograph and had the longest duration of faulting ever observed, between 8.3 and 10 minutes. It caused the entire planet to vibrate as much as 1 centimeter (0.4 inches) and triggered other earthquakes as far away as Alaska. Its epicenter was between Simeulue and mainland Indonesia. The plight of the affected people and countries prompted a worldwide humanitarian response. In all, the worldwide community donated more than US$14 billion (2004) in humanitarian aid. The event is known by the scientific community as the Sumatra–Andaman earthquake. The resulting tsunami was given various names, including the 2004 Indian Ocean tsunami, South Asian tsunami, Indonesian tsunami, the Christmas tsunami, and the Boxing Day tsunami.”

What was particularly remarkable about this particular earthquake is that this was the first tsunami of this magnitude which was so widely filmed and seen in ‘real time.’ This scenario was repeated on March 11, 2011 when another mega thrust earthquake triggered yet another deadly tsunami, this time in Japan.

Until the videos started to pour in, I could only imagine what a tsunami might look like. To see how the water literally overpowers everything in its path is truly unfathomable. For the scientific community the knowledge gained is, no doubt, invaluable but we are made somber with the understanding that over 230,000 people were lost in this one event.

There have, of course, been other mega thrust quakes and tsunamis in the world. Scientists now believe that the west coast of the United States and Canada was hit by such an event on January 26, 1700. Information on the Cascadia quake has been pieced together through written Japanese records of a tsunami which did not correlate with a known earthquake in the region on that date. Evidence of the event has been  via oral stories of the indigenous peoples of the Pacific Northwest and also physical evidence from British Columbia south to Northern California.

Is the Pacific Northwest at risk for a mega-thrust quake? Such an event strikes the coast, on average, every 500 years and scientists believe there have been at least seven such events in the past 3,500 years. It is now 317 years since the 1700 quake.

Tsunami evacuation sign.pngDown at Long Beach, Washington, there are the blue tsunami signs which direct people to routes that would, ostensibly, lead them to higher ground. Recently I saw a program on HGTV where a family was purchasing a vacation home ten miles north in Ocean Park. Personally, I would buy something no more than a mile north of Long Beach; in lesser known Seaview would be better. From that location there is a road which quickly gets you up on top of a rather tall promontory. If, however, one happens to be on the north end of the peninsula when such an earthquake occurs it’s probably best to carry an auto- inflatable rubber boat with you when visiting the coast.

For all you other science nerds out there, here are two Wikipedia links for you:

https://en.wikipedia.org/wiki/2004_Indian_Ocean_earthquake_and_tsunami

https://en.wikipedia.org/wiki/Cascadia_subduction_zone

And two YouTube videos of the 2004 Boxing Day tsunami:

https://www.youtube.com/watch?v=my4UD9Wfqvk

https://www.youtube.com/watch?v=3YOf44bNzw4

The second one is much longer but it is a documentary of why and how the tsunami occurred.