Description

Background to the stories: Indigenous oral accounts of this large earthquake and its tsunami were recorded from Vancouver Island to northern California. The account we read was told by late Chief Louis Clamhouse of Huu-ay-aht First Nation, recorded in his language in 1964, and translated. It has minimal changes to it to give a sense of how it was told. The tsunami from the 1700 earthquake crossed the Pacific in about nine hours and was recorded by officials in Japan. We’ll also read the Japanese account. We’ll look at the modern science story which includes evidence upholding both the Huu-ay-aht and Japanese stories. Each story (traditional, clerical, and scientific) has ways of validating itself as a true story. Facts in the traditional story were verified through specific ancestors, genealogy, memorable rituals, marriages, lives lost, and territories. The Japanese record was validated by sharing records with magistrates and accounting for emergency supplies given to tsunami survivors. The scientific account came from four different lines of peer-reviewed, published evidence and by many scientists working together across disciplines and international boundaries. Read the three stories.

The Modern Science Story follows in very simplified form. The dense, oceanic, tectonic Juan de Fuca plate that normally, sub-ducts (dives) slowly under the less dense, North American plate, was stuck in late 1699. When it suddenly became unstuck in January 1700, it caused a mega-thrust earthquake calculated to be 9.0 on the Richter scale.

Both the Juan de Fuca and Pacific plates arise from molten rock, coming up through the Endeavour Ridge, west of what is now southwestern Canada and the northwestern USA. The Pacific plate moves to the west towards Asia and the Juan de Fuca plate moves eastward about as fast as your fingernails grow. As the Juan de Fuca plate ‘slides’ under the North American plate, moving batches of small tremors release energy from the subduction (one going under the other).

Today, using GPS technology we can actually measure the land moving east-west in longitude and the up-down movement in elevation. A mega-thrust earthquake results from the tectonic plates getting stuck, the energy of these very large moving masses of rock builds up as does the elevation of the continental plate at its edges where it is literally pushed up. Then something gives and a huge release of energy shakes the land and sea. The shaking starts landslides and underwater slides causing tsunamis: waves with very large heights and speeds. On land, the shaking liquefies wet sandy and silty areas and the quick-release drops land elevations causing seawater flooding, which kills low lying coastal forests and along with tsunamis, deposits marine ‘evidence’ inland.

Until scientists discovered the “scientific” evidence themselves and confirmed the date with the written Japanese account, traditional First Nations’ knowledge was discounted. The ‘triangulation’ of these stories might be an example of the reconciliation of different ways of knowing. Even though it took science almost 300 years to catch-up with traditional knowledge, science accepts the truth in the oral account at last. Only pieces of the stories are presented here, so if you have time read a fuller account in the book At Risk[1] by John Clague and others as well as the whole Chief Louis Clamhouse story[2] as it was recorded and translated in the book Between Ports Alberni and Renfrew. Names and place-names are Anglicized here. This story belongs to Huu-ay-aht.

Chief Louis Clamhouse “This is the story about the first Anacla or Pachena Bay people. It is said that they were a big group at the time of, him whose name was Hayoqwis’is ‘Ten-head-on-beach.’ He was the chief; he was of the Pachena Bay tribe; he owned the Pachena Bay country. Their village site (one of several) was Lota’a; they of Lota’a lived there….They were members of the Pachena tribe”. …(Chief Louis describes details of a marriage protocol that tested the strength and ability of four sons of the Huu-ay-aht Kix’iin and how one son died trying. The Kix’iin chief had come to Lota’a to perform a “ceremonial woman purchase” involving the eldest daughter of Hayoqwis’is. This was “before the big earthquake before the big flood".)

“They (Huu-ay-aht) got in marriage, the elder daughter. The Pachena Bay chief brought (territory) as dowry for his elder daughter to my grandfather’s ancestor…. who now has many descendants. It is them now, who are descendants of the first Pachena Bay people. There is no one left alive (at Lota’a) due to what this land does at times. They had practically no way or time to save themselves. I think it was at nighttime that the land shook. It was a sandy beach. It was floating, it is said, consisting only of sand, … They were at Lota’a and they simply had no time to get hold of canoes, no time to get awake. They sank all at once, were all drowned; not one survived. Only his (Hayoqwis’is) older daughter went to Kix’iin (Huu-ay-aht) as a bride from whom my former grandfather was descended. It is said no one ever knew what happened. I think a big wave smashed into the beach. The Pachena Bay people were lost. Nothing was known of what happened and what became of them. But they on their part who lived at Ma:lts’a:s “House-Up-Against-Hill’ (across the bay from Klutus Point), the wave did not reach because they were on high ground. Right against a cliff were the houses on high ground at M’a:lsit “Coldwater-Pool”. Because of that, they came out alive. They did not drift out to sea with the others. Everything then drifted away; everything was lost and gone…”

Japanese Official Account: translated from a written record of the aftermath in Kuwagaski, Honshu Island where the tsunami that had no shaking associated, swept along about 1,000 kilometers of shoreline with waves up to several meters high in some locations. (from Clague et al (2006)) “The tsunami arrived at night on January 27, 1700; villagers fled to high ground; the water destroyed thirteen houses and set off fires that burned 20 more; in response, magistrates in nearby Miyako issued rice to 159 persons and sought wood for shelters; they kept other officials informed of their emergency efforts.”

Sources:

[1] J. Clague et al (2006) At Risk: Earthquakes and Tsunamis on the West Coast

[2] E.Y. Arima et al (1991) Between Ports Alberni and Renfrew: Notes on West Coast Peoples.

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Task

Post your answers in a discussion!

1. List four things that happen when tectonic plates suddenly move after being stuck for a while.

2. Compare and Contrast the three story-telling methods: Oral Knowledge, Government Record, and Scientific Record. What is the strength and weakness of each method? How can we use them collaboratively? 

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To take the section quiz, click HERE

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Learning Objectives

Be prepared, not scared. Help prepare for an earthquake/tsunami at home and school. Do you know about taking cover and holding on? Ask your teacher to help your class practice the drill. Do you already have emergency kits or ‘go-bags’ ready? What are the five items in your ‘go bag’ for emergencies? If you don’t have a go-bag, what are your top five items for the grab-bag that you are going to put together? If you live in a coastal community, take a look at a map with one of your adults and talk through high land escape routes in different locations and where you would meet up with family if you get separated. Get involved with your local community emergency response group and start a youth volunteer section.

The data presented in the ONC graph below (See Figure 1.), was compiled from NEPTUNE data collected after the devastating 2011 mega-thrust earthquake, near Japan. Now, there are even more sensors. West Coast Vancouver Island now has a better forecasting system for tsunamis as part of Ocean Networks Canada’s near field detectors which gives valuable time and wave height and speed information.

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