Pachena Bay

Last updated

Pachena Bay
Canada British Columbia relief location map.jpg
Red pog.svg
Pachena Bay
Vancouver Island
LocationBritish Columbia, Canada
Coordinates 48°46′37″N125°07′46″W / 48.7770°N 125.1295°W / 48.7770; -125.1295 (PachenaBay) Coordinates: 48°46′37″N125°07′46″W / 48.7770°N 125.1295°W / 48.7770; -125.1295 (PachenaBay)
Ocean/sea sourcesPacific Ocean
Basin  countriesCanada
Max. length3.29 km (2.04 mi)
Max. width1.27 km (0.79 mi)
Surface area4.9 km2 (1.9 sq mi)
Average depth7 m (23 ft)
Max. depth16.6 m (54 ft)
Settlements Huu-ay-aht First Nations

Pachena Bay is located 13 km (8.1 mi) south of Bamfield in Pacific Rim National Park at the southern end of Vancouver Island, British Columbia, Canada. It was the location of a First Nation's village that was destroyed by a tsunami in 1700.

Contents

Origin of name

"This word is derived from the Nitinaht Indian name for the site of Port Renfrew, but by mistake, the anglicized name Pachena was applied to a point further up the coast that had a nearly identical configuration. Pachena in its original form means either 'seafoam' or 'foam on the rocks.' [1]

Pachena Bay adopted in the 5th Report of the Geographic Board of Canada, 30 June 1904, as labelled on British Admiralty Chart 592, 1861 et seq, and on John Buttle's "Map of the Country between Barclay Sound & Nanaimo" by the Vancouver Island Exploring Expedition, 1864 (plan 2T67). [1]

The Huu-ay-aht (Ohiaht) First Nation live here; they call this bay "Anacla." [1]

Huu-ay-aht First Nations

Pachena Bay is home to the Huu-ay-aht First Nations village of Anacla, "which aboriginal oral history says was devastated when an ancient earthquake convulsed the West Coast of North America." [2]

The Huu-ay-aht First Nations is a First Nations band government based on Pachena Bay about 300 km (190 mi) northwest of Victoria, British Columbia on the west coast of Vancouver Island in British Columbia, Canada. The HFN is a member of the Nuu-chah-nulth Tribal Council and is a member of the Maa-nulth Treaty Society.

Cascadia earthquake

On 26 January 1700, an earthquake, one of the largest earthquakes on record, ruptured the Cascadia subduction zone offshore from Vancouver Island to northern California, creating a tsunami that wiped out the village of Pachena Bay leaving no survivors.

"First Nations from Vancouver Island to Northern California describe the earthquake and tsunami in similar legends and artwork involving a life-and-death struggle between a thunderbird and a whale that caused the earth to shake violently and the seas to wash away their people and homes...[T]he ancient quake and tsunami devastated the western shores of Vancouver Island and the eastern coast of Japan.

Meissner 2015

An estimate of how many generations had passed since the event [3] — which can be traced back to a date range in the late 1600s or early 1700s, [4] or which concur with the event's timing in other ways help pinpoint the timing. The Huu-ay-aht legend of a large earthquake and ocean wave devastating their settlements at Pachena Bay, for instance, speaks of the event taking place on a winter evening shortly after the village's residents had gone to sleep. [2] Masit was the only community on Pachina Bay not to have been wiped out, as it sat on a mountainside approximately 75 feet (23 m) above sea level. [5] Nobody else from Pachina Bay survived the event — Anacla aq sop, a young woman who happened to be staying at Kiix?in on the more tsunami-sheltered Barkley Sound at the time of the event, came to be known as the last living member of her community.

Although residents still live primarily in lower-lying areas, they are evacuated to the administration building when a tsunami warning is issued; [2] this is an interim step toward a longer-term plan which will eventually see the residents relocated to higher ground as well. [6]

Cascadia subduction zone, Vancouver Island JuandeFucasubduction.jpg
Cascadia subduction zone, Vancouver Island

In 1996, a team of researchers linked the orphaned 1700 tsunami in Japan with a magnitude 9 earthquake and tsunami in North America in a Trans-Pacific reunion. [7] :94–95 [8] [9] Scientists "dated the earthquake to the evening of January 26, 1700" and approximated its size as magnitude 9. [7] :42–43

Tree-ring dating had securely linked the giant 1700 North American earthquake. [8] :96

According to a 2005 United States Geological Survey (USGS) report, [8] :98

"The 1700 Cascadia earthquake probably was such a giant. It likely broke at least 1,000 kilometres of the boundary between the subducting Juan de Fuca Plate and the overriding North America Plate—a rupture about as long as California, or about Japan's length’s main island, Honshu. On the seaward half of the rupture, the plates probably lurched past one another by about 20 meters. The magnitude was probably in the range M 8.7-9.2."

USG nd

Before the mid-1980s, scientists were not certain that British Columbia had ever seen the kind of massive subduction earthquake that wreaks maximum havoc on land and causes tsunamis. [10]

Fragments of wood preserved in the soil tell of coastal marshes destroyed by a tsunami. [10] The excavation of a marsh reveals another layer of the same plant material, separated by a layer of sand. [10] Tsunamis wash massive amounts of sand ashore, covering a marsh, which slowly builds up again. [10] The deeper they dig, the more layers scientists find. [10]

Thanks in part to oral and written accounts, we now know that such an earthquake took place off the coast of Vancouver Island, rupturing a subduction fault all the way to northern California. [10] What's more, we can actually pinpoint the date, year and time: 26 January 1700, 9 p.m. Pacific Time. [10]

These sources were key to understanding that massive subduction earthquakes have struck this coast every 250 to 850 years. [10]

“A tsunami struck Kuwagasaki around midnight….water destroyed 13 houses outright and set off fires that destroyed 20 more,” according to one document. [10] The tsunami also caused a shipwreck and damaged rice stores. [10]

Using wave heights and arrival times recorded by the Japanese, tsunami scientists and seismologists worked backward, concluding that the tsunami originated with a magnitude 8.7–9.2 earthquake off the coast of Vancouver Island. [10]

Japanese history aligns perfectly with what we now know about subduction earthquakes and stories that generations of Indigenous people on Vancouver Island have passed on through generations. [10]

“They had practically no way or time to try to save themselves,” said one storyteller. “I think it was at nighttime that the land shook. [10] I think a big wave smashed into the beach. The Pachena Bay people were lost.” [10]

“It began in the middle of the night, and shaking was so severe that it made people sick,” said another storyteller. [10] “It threw down their houses and brought great masses of rock down from the mountains.” [10]

Related Research Articles

1700 in Canada

Events from the year 1700 in Canada.

Juan de Fuca Plate A small tectonic plate in the eastern North Pacific

The Juan de Fuca Plate is a small tectonic plate (microplate) generated from the Juan de Fuca Ridge that is subducting beneath the northerly portion of the western side of the North American Plate at the Cascadia subduction zone. It is named after the explorer of the same name. One of the smallest of Earth's tectonic plates, the Juan de Fuca Plate is a remnant part of the once-vast Farallon Plate, which is now largely subducted underneath the North American Plate.

1700 Cascadia earthquake Megathrust earthquake in the North West Pacific region

The 1700 Cascadia earthquake occurred along the Cascadia subduction zone on January 26, 1700, with an estimated moment magnitude of 8.7–9.2. The megathrust earthquake involved the Juan de Fuca Plate from mid-Vancouver Island, south along the Pacific Northwest coast as far as northern California. The length of the fault rupture was about 1,000 kilometers, with an average slip of 20 meters (66 ft).

Bamfield Place in British Columbia, Canada

Bamfield is a community that is surrounded by Crown Land, First Nation Lands belonging to the Huu-ay-aht Nations, and portions of the Pacific Rim National Park, located on Barkley Sound, Vancouver Island in British Columbia. The community, with a population of 179 as of 2016, is divided by Bamfield Inlet.

Cascadia subduction zone Convergent plate boundary that stretches from northern Vancouver Island to Northern California

The Cascadia subduction zone is a convergent plate boundary that stretches from northern Vancouver Island in Canada to Northern California in the United States. It is a very long, sloping subduction zone where the Explorer, Juan de Fuca, and Gorda plates move to the east and slide below the much larger mostly continental North American Plate. The zone varies in width and lies offshore beginning near Cape Mendocino, Northern California, passing through Oregon and Washington, and terminating at about Vancouver Island in British Columbia.

Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthquakes are the planet's most powerful, with moment magnitudes (Mw) that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes.

The seismicity of the Sanriku coast identifies and describes the seismic activity of an area of Japan. Seismicity refers to the frequency, type and size of earthquakes experienced over a period of time. The Sanriku coast is a descriptive term referring to the coastal areas of the former provinces of Rikuō in Aomori, Rikuchū in Aomori, and Rikuzen in Miyagi.

The 1957 Andreanof Islands earthquake took place on March 9 with a moment magnitude of 8.6 and a maximum Mercalli intensity of VIII (Severe). It occurred south of the Andreanof Islands group, which is part of the Aleutian Islands arc. The event occurred along the Aleutian Trench, the convergent plate boundary that separates the Pacific Plate and the North American Plates near Alaska. A basin wide tsunami followed, with effects felt in Alaska and Hawaii. Total losses were around $5 million.

Huu-ay-aht First Nations First Nations band government in British Columbia, Canada

The Huu-ay-aht First Nations (HFN) is a First Nations band government based on Pachena Bay about 300 km (190 mi) northwest of Victoria on the west coast of Vancouver Island in British Columbia, Canada. The traditional territories of the HFN make up the watershed of the Sarita River. The HFN is a member of the Nuu-chah-nulth Tribal Council and is a member of the Maa-nulth Treaty Society. It has recently completed and ratified its community constitution and has successfully ratified the Maa-nulth Treaty on 28 July 2007. The Legislative Assembly of British Columbia passed the Maa-nulth First Nations Final Agreement Act on Wednesday, 21 November 2007 and celebrated with the member-nations of the Maa-nulth Treaty Society that evening.

Alberni Inlet

Alberni Inlet is a long, narrow inlet in Vancouver Island, British Columbia, Canada, that stretches from the Pacific Ocean at Barkley Sound about 40 km (25 mi) inland terminating at Port Alberni. It was named by the Spanish explorer Francisco de Eliza after Pedro de Alberní y Teixidor, Captain of the Free Company of Volunteers of Catalonia who was appointed in the Spanish fort in Nootka Sound from 1790 to 1792. The inlet includes traditional territories of the Ucluelet, Uchucklesaht, Huu-ay-aht, Hupacasath, and Tseshaht peoples, who are part of the Nuu-chah-nulth Tribal Council people.

Kiix-in, or Kiix?in , earlier romanized as Keeshan, was the principal residence of the Huu-ay-aht (Ohiaht) group of the Nuu-chah-nulth people. The name is onomatopoeic, and comes from the sound of waves crashing against the rocks below the village. It was initially romanised as "Keeshan", but was redesignated "Kiix-in " in line with the Maa-nulth Treaty.

The 1992 Cape Mendocino earthquakes occurred along the Lost Coast of Northern California on April 25 and 26. The three largest events were the M7.2 thrust mainshock that struck near the unincorporated community of Petrolia midday on April 25 and two primary strike-slip aftershocks measuring 6.5 and 6.6 that followed early the next morning. The sequence encompassed both interplate and intraplate activity that was associated with the Mendocino Triple Junction, a complex system of three major faults that converge near Cape Mendocino. The total number of aftershocks that followed the events exceeded 2,000.

The 1994 Java earthquake occurred on June 3 at 01:17:37 local time on June 2, at 18:17:37 GMT off the coast of Indonesia. The epicenter was off the eastern part of the southern Java coast, near the east end of the Java Trench.

2012 Haida Gwaii earthquake

The 2012 Haida Gwaii earthquake occurred just after 8:04 p.m. PDT on October 27. The shock had a moment magnitude of 7.8 and a maximum Mercalli Intensity of V (Moderate). The earthquake's epicentre was on Moresby Island of the Haida Gwaii archipelago. This was the second largest Canadian earthquake ever recorded by a seismometer, after the 1949 Queen Charlotte Islands earthquake, about 135 kilometres (84 mi) away. One person died due to a car crash related to the tsunami in Oahu, Hawaii.

Kenji Satake is a Japanese seismologist who has made significant contributions to subduction and tsunami research. Along with Brian Atwater and David Yamaguchi, Satake assembled disparate pieces of information regarding a Japanese tsunami that had no known origin. The three scientists worked together to pinpoint a date, time, and location for the 1700 Cascadia earthquake – 9 p.m. on January 26, 1700 – on the Cascadia Subduction Zone off the Pacific Northwest coast of North America.

2013 Craig, Alaska earthquake Earthquake in Alaska and British Columbia

The 2013 Craig, Alaska earthquake struck on January 5th, at 12:58 am (UTC–7) near the city of Craig and Hydaburg, on Prince of Wales Island. The Mw 7.5 earthquake came nearly three months after an Mw  7.8 quake struck Haida Gwaii on October 28, in 2012. The quake prompted a regional tsunami warning to British Columbia and Alaska, but it was later cancelled. Due to the remote location of the quake, there were no reports of casualties or damages.

The 1973 Nemuro earthquake, also known as the Nemuro-Oki earthquake in scientific literature, occurred on June 17 at 11:55 local time. It stuck with an epicenter just off the Nemuro Peninsula in northern Hokkaidō, Japan. It measured 7.8 to 7.9 on the moment magnitude scale (Mw ), 8.1 on the tsunami magnitude scale (Mt ) and 7.4 on the Japan Meteorological Agency magnitude scale (MJMA ).

1585 Aleutian Islands earthquake Seismic event

The 1585 Aleutian Islands earthquake is the source of a vaguely–described tsunami along the Sanriku coast of Japan on June 11, 1585. The event was misdated to 1586 and thought to be generated by the 1586 Lima–Callao earthquake. The misdating also led to it being attributed with the deadly 1586 Tenshō earthquake. The source earthquake is now determined to be along the Aleutian Islands. Evidence from tsunami deposit and coral rocks in Hawaii led to the inference that this was a large megathrust earthquake occurring on the Aleutian subduction zone with a moment magnitude (Mw ) as large as 9.25.

2021 Chignik earthquake 7th largest earthquake in the US

An earthquake occurred off the coast of the Alaska Peninsula on July 28, 2021, at 10:15 p.m. local time. The large megathrust earthquake had a moment magnitude of 8.2 according to the United States Geological Survey (USGS). A tsunami warning was issued by the National Oceanic and Atmospheric Administration (NOAA) but later cancelled. The mainshock was followed by a number of aftershocks, including three that were of magnitude 5.9, 6.1 and 6.9 respectively.

Sarita River River in British Columbia, Canada

The Sarita River is an approximately 25 km (16 mi)-long river on the west coast of Vancouver Island, British Columbia, Canada, just north of the hamlet of Bamfield.

References

  1. 1 2 3 "Pachena Bay". BC Geographical Names . Retrieved 25 December 2020.
  2. 1 2 3 Meissner, Dirk (18 January 2015), "Earth will rip open like a zipper, expert says, when overdue Vancouver Island quake strikes", Toronto Star , retrieved 19 January 2015
  3. Ruth S. Ludwin; Robert Dennis; Deborah Carver; Alan D. McMillan; Robert Losey; John Clague; Chris Jonientz-Trisler; Janine Bowechop; Jacilee Wray; Karen James (2005), "Dating the 1700 Cascadia Earthquake: Great Coastal Earthquakes in Native Stories" (PDF), Seismological Research Letters, 76 (2): 140–148, doi:10.1785/gssrl.76.2.140, archived from the original (PDF) on 24 July 2015, retrieved 24 July 2015
  4. Kathryn Schulz (20 July 2015). "The Really Big One". The New Yorker .
  5. "Prepare for next tsunami, says chief". Raven's Eye, Vol. 8, No. 9, 2009.
  6. "Monster earthquake threat looms over B.C. coastal communities" Archived 3 February 2019 at the Wayback Machine . Vancouver Sun , 9 March 2012.
  7. 1 2 Satoko, Satake; Shimazaki, K.; Tsuji, Yoshinobu; Ueda, Kazue (1996). "Time and size of a giant earthquake in Cascadia inferred from Japanese tsunami records of January 1700". Nature. 379 (6562): 246–249. Bibcode:1996Natur.379..246S. doi:10.1038/379246a0. S2CID   8305522.
  8. 1 2 3 Atwater, Brian F.; Satoko, Musumi-Rokkaku; Kenji, Satake; Tsuji, Yoshinobu; Ueda, Kazue; Yamaguchi, David K. (2005), "The Orphan Tsunami of 1700—Japanese Clues to a Parent Earthquake in North America" (PDF), USG, Professional Paper, no. 1707, p. 144, retrieved 19 January 2015
  9. Jacoby, Gordon C.; Bunker, Daniel E.; Benson, Boyd E. (1997), "Tree-ring evidence for an A.D. 1700 Cascadia earthquake in Washington and northern Oregon" (PDF), Geology, 25 (11): 999, Bibcode:1997Geo....25..999J, doi:10.1130/0091-7613(1997)025<0999:TREFAA>2.3.CO;2 , retrieved 19 January 2015
  10. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 McKendy, Joe. "The Mystery of the Missing Village". Government of Canada. Retrieved 18 December 2020.