Evidence from archaeological sites from the British Columbia coast to the southern tip of South America show that First Peoples had settled on both continents by at least 18,000 years ago, according to authors T.J. Braje at San Diego State University in San Diego, CA; T.D. Dillehay at Vanderbilt University in Nashville, TN; J.M. Erlandson at University of Oregon in Eugene, OR; R.G. Klein at Stanford University in Stanford, CA; T.C. Rick at National Museum of Natural History, Smithsonian Institution in Washington, DC.
The paper also says the DNA genomic data suggests a northeast Asian origin for Native American ancestors some time in the past 20,000 years.
One of the key sites cited in the paper is Triquet Island in the traditional territory of the Heiltsuk Nation which has been dated to at least 14,000 years ago. Heiltsuk oral history has marked the island for generations, William Housty a member of the Heiltsuk told CBC News at the time the discovery was officially announced in April 2017, “Heiltsuk oral history talks of a strip of land in that area where the excavation took place. It was a place that never froze during the ice age and it was place where our ancestors flocked to for survival.”
The authors of the review say the new consensus on the “kelp highway” is a “dramatic intellectual turnabout” from the original idea that the first indigenous settlers followed an ice free corridor from a land bridge from Siberia down the centre of North America to form the “Clovis Culture”
The land bridge between northeast Asia and North America, commonly called Beringia, came about when sea levels fell during the last ice age. Although the original Beringia hypothesis has been disputed by some First Peoples, the paper says the Beringia hypothesis is still a factor—but much farther back in time, now about 24,000 years ago.
The paper says:
most archaeologists and other scholars now believe that the earliest Americans followed Pacific Rim shorelines from northeast Asia to Beringia and the Americas.
According to the kelp highway hypothesis, deglaciation of the outer coast of North America’s Pacific Northwest about 17,000 years ago created a possible coastal corridor rich in aquatic and terrestrial resources along the Pacific Coast, with productive kelp forest and estuary ecosystems at sea level and no major geographic barriers
The paper says that kelp resources extended as far south as Baja California, and then—after a gap in Central America, where productive mangrove and other aquatic habitats were available—picked up again in northern Peru, where the cold, nutrient-rich waters from the Humboldt Current supported kelp forests as far south as Tierra del Fuego.
The other sites cited in the paper are
Huca Prieta, Peru 15,000 to 14,500 years ago
Paisley Caves, Oregon 14,000 years ago
Monte Verde, Chile 14,500 years ago
Page-Ladson, Florida 14,500 years ago
Channel Islands California 13,000 years ago
Quebrada Santa Julia and Quebrada Huentelauquén , Chile 13,000 years ago
Quebrada Tacahuay Peru 13,000 years ago
Quebrada Jaquay, Peru 13,000 years ago
In an earlier article in Science in August, Knut Fladmark, a professor emeritus of archaeology at Simon Fraser University who was one of the first to propose a coastal migration into the Americas back in 1979, said: “The land-sea interface is one of the richest habitats anywhere in the world,” noting that early Americans knew how to take full advantage of its abundant resources.
Testing the kelp highway hypothesis is challenging, the scientists say, because much of the archaeological evidence would have been submerged by rising seas since the end of the last “glacial maximum,” about 26,500 years ago.
The earlier that the First Peoples arrived, that means the land they originally settled is now the further offshore from the current coast (land which is now likely also at greater depth under the current ocean). So the review says that finding the evidence means that, “enlarging already vast potential search areas on the submerged continental shelf.”
The authors say:
Although direct evidence of a maritime pre-Clovis dispersal has yet to emerge, recent discoveries confirm that late Pleistocene archaeological sites can be found underwater. Recent discoveries at the Page-Ladson site, in Florida produced 14,500-year-old butchered mastodon bones and chipped stone tools in the bottom of Florida’s Aucilla River.
The report says that “Several multidisciplinary studies are currently mapping and exploring the submerged landscapes of North America’s Pacific and Gulf of Mexico coasts, searching for submerged sites. .
The review says that for much of the 20th century, most archaeologists believed humans first colonized the Americas about 13,500 years ago via the overland route that crossed Beringia and followed a long and narrow, mostly ice-free corridor to the vast plains of central North America. There, according to the earlier theories, Clovis people and their descendants hunted large game and spread rapidly through the New World.
This was initially confirmed by twentieth-century discoveries of distinctive Clovis artifacts throughout North America. Some finds associated with mammoth or mastodon kill sites, supported this “Clovis-first” model.
The early studies decided then that “North America’s coastlines and their rich marine, estuarine, riverine, and terrestrial ecosystems were peripheral to the story of how and when the Americas were first settled by humans.”
Now the recent work along the Pacific coastlines of North and South America has revealed that these environments were settled early and continuously, providing a rich diversity of subsistence options and technological resources for New World hunter-gatherers.
At the moment, there is little evidence on the coast so far of the kind of stone tools and fishtail points that had previously provided a road map that archaeologists used to trace the spread of “Clovis” Paleoindians throughout the Americas. Such a roadmap is lacking for “pre-Clovis” sites on the coast.
One proposal is that distinctive stemmed (“tanged”) chipped-stone projectile points, crescents (lunate-shaped), and leaf-shaped bifaces found in Japan, northeast Asia, western North America, and South America could be potential markers of an earlier coastal migration and ties to Ice Age peoples in East Asia.
The problem of finding final proof of the kelp highway is that the First Peoples followed a coastal route from Asia to the Americas, so that finding evidence for their earliest settlements will require careful consideration of the effects of sea level rise and coastal landscape evolution on local and regional archaeological records.
The scientists note that around the globe, evidence for coastal occupations between about 50,000 and 15,000 years ago are rare because of postglacial sea level rise, marine erosion, and shorelines that have migrated tens or even hundreds of kilometers from their locations at the ice age glacial maximum.
They say overcoming these obstacles requires interdisciplinary research focused on coastal areas with relatively steep offshore bathymetry, formerly glaciated areas where ancient shorelines have not shifted so dramatically, or the submerged landscapes that are one of the last frontiers for archaeology in the Americas
UPDATED with comments from District of Kitimat, Terrace and the Gitga’at Nation
A preliminary seismic hazard assessment by Natural Resources Canada has identified possible earthquake scenarios for the Douglas Channel near Hartley Bay, Terrace and Bella Bella.
The same studies indicate that while Kitimat may not be directly in a seismic zone prolonged earthquakes cause some damage in Kitimat depending on the earthquake and the condition of the soil in certain parts of the District. One model scenario says that in the event of a magnitude 8.0 earthquake off the west coast of Haida Gwaii, given certain soil conditions, there might actually be more damage in Kitimat than on the islands.
Susceptibility to landslides
That assessment, part of the overall the study by the Geological Survey of Canada indicates that the north coast of British Columbia from Prince Rupert to Bella Bella is likely face to “seismically induced ground failure”– mostly landslides.
Overall, the report says that on a scale of 1 to 6 (6 representing the highest
susceptibility), the majority of the west coast of BC “exhibits landslide susceptibility values of 5 to 6, which is significantly higher than the rest of Canada.”
In British Columbia the landslides are most likely to be triggered by delayed melting of the annual snow pack, heavy rains, bank erosion and site loading and caused long-lasting damning of the river causing “damage to pipelines, rail, and forestry, as well as fish habitats.”
So far no recent landslides along the northern British Columbia coast are known to be caused by earthquakes, the reports say “the existence of numerous landslides strengthens the likelihood of seismically induced ground failures… due to the high levels of seismicity….it is expected that the increased likelihood of strong ground shaking (with long durations) will increase the landslide susceptibility.”
It was only after the 2012 Haida Gwaii earthquake and with what the Geological Survey of Canada calls “a growing number of on-going and planned infrastructure projects, BC’s north coast is emerging as a region of high strategic importance to Canada’s economy,” that studies began in area where “there has been minimal research to understand earthquake hazards.”
Now that studies have begun the Geological Survey has given the region its own new acronym BCNC (BC North Coast). Haida Gwaii is not part of BCNC, although earthquakes on those islands would likely impact the coast.
The Geological Survey says that historically “the BCNC has been seismically quiescent.” As a result “seismic monitoring and research related to the BCNC has been minimal.” That meant while larger earthquakes were “felt and recorded,” the configuration of the Canadian National Seismograph Network did not allow earthquakes less than approximately magnitude 2.1 to be monitored in northern BC.
Now the Geological Survey is looking at “long-term, continuous monitoring of micro seismicity, combined with geodetic and paleo seismic techniques” that could be used to study at the possibility of large earthquakes, including a possible fault on the lower Douglas Channel.
Since the studies began in August 2014, the Geological Survey identified 145 earthquakes within the study area, many too small to be felt since they are less than magnitude 2.0. Those earthquakes, however, were picked up by the new and improved instrumentation used by the earthquake monitors.
The two reports one on “seismic hazards” and the second on “geohazards” says five “temporary seismonitors” (download reports from links below) were installed within the BCNC while some older stations were upgraded, saying, “It is expected that these new stations will be aid in locating small earthquakes” that were not previously detected by the existing network. The Geological Survey also installed ground movement monitoring GPS units along the coast.
The use of the term “temporary” raises the question about how much ongoing monitoring is planned.
The study also notes that the current data is not included in the seismic standards in the current National Building Code of Canada, which in turn is based on the Natural Resources Canada Seismic Hazard Map. That may mean that municipalities in the BC North Coast region, in the future, as the seismic studies continue, may have to consider updating building codes, especially in areas of “softer soils” as opposed to harder rock.
“Fault-like structure” on Douglas Channel
Over the years some small earthquakes have also been recorded on what the Geological Survey calls the “recently mapped fault-like structure” on Douglas Channel which was discovered in 2012. The survey is still calling it “fault-like” because it has not yet been confirmed as an active fault. A new map in the study shows that the “fault” runs from the southern tip of Gribbell Island, down the centre of Whale Channel east of Gil Island and then along the western coast of Princess Royal Island.
The study identified “a small, unfelt swarm of earthquakes between magnitude 1.7 and 2.0 between September 13 and 14, 2010 near Gil Island.”
There is also the previously identified ancient Grenville Channel Fault (ancient and believed inactive because it dates from the Cretaceous, the age of the dinosaurs) that runs from along Grenville Channel from Porcher Island in the north to Klemtu in the south which has experienced small earthquakes.
The report says geological studies of the Douglas Channel “fault-like structure” are a priority because, “Should this structure be determined to be an active fault, it would pose significant risk of earthquake-triggered landslides (and subsequent tsunami) from the susceptible Douglas Channel hill slopes.”
Clay and sand in Kitimat
The report also calls for more studies the local geology and soil conditions in the Kitimat Valley. A study back in 1984 by John Clague of Simon Fraser University showed that as the glaciers retreated during the last Ice Age there were “periods of stagnation” resulting in sediments that are thicker than other regions of British Columbia, Clague reported that in parts of Kitimat, the glacial moraine is hundreds of metres thick.
After the glaciers were gone, the sea levels rose and glaciomarine sediments (clay, silt up to 60 metres thick) were deposited until the sea level fell to present-day levels. The report says that as these marine deposits were exposed to fresh water, salts were leached out resulting in saturated, porous sediments, including clay, which are prone to failure. Boreholes in the Kitimat area show that the clay and sediments above the bedrock can range from 17 metres to 106 metres.
The report notes the presence of clay soils “can amplify ground shaking and secondary effects” as happened in November 1988 when there was an earthquake in the Saguenay region of Quebec.
Originally reported as a 6.2 magnitude but later downgraded to 5.9, on Nov. 25, 1988, the major earthquake was centered near the Quebec cities of Chicoutimi and Jonquière, with aftershocks felt as far away as Toronto, Halifax and Boston. The quake lasted for two minutes, catching thousands of people off guard and leaving buildings damaged and power out for hundreds of thousands of Quebecers.
The report says the most significant event within the BC North Coast study region (which as mentioned doesn’t include Haida Gwaii) was a magnitude 4.9 earthquake approximately 20 kilometers southwest of Terrace on November 5, 1973, which was felt as far as 120 kilometers away, with some minor damage (broken windows and cracked plaster) reported near the epicentre. The main shock at Terrace was preceded by a magnitude 2.5 foreshock four hours before, and followed by a felt magnitude 3.7 aftershock the next day.
Bella Bella at risk
Another area most at risk, according to the report, is southern part of the BC North Coast zone, near Bella Bella, which is close to the northern section Cascadia Subduction Zone a “1,000 kilometre long dipping fault that stretches from Northern Vancouver Island to Cape Mendocino California” which one day will cause a major earthquake along the fault.
The report says that a magnitude 9.0 or higher earthquake in the northern Cascadia Subduction zone close to Bella Bella would be similar to the March 2011 earthquake in Japan and the 1964 Good Friday earthquake in Alaska.
For the northern part of the BC North Coast region, hazards could come from either a major earthquake off Haida Gwaii or a similar earthquake in south-eastern Alaska.
The greatest hazard would come from “long period” earthquakes greater than magnitude 6.75 with an epicentre between 300 and 350 kilometers away where the shaking lasts longer than one second.
The Geological Survey modeled three possible scenarios for major earthquakes in the BC North Coast Region.
Model #1. A magnitude 8.0 Earthquake at Haida Gwaii
The model looked at a “plausible maximum predicted” magnitude 8.0 thrust fault earthquake off the west coast of Haida Gwaii which would be twice as strong in the fault area as the 7.8 quake on October 28, 2012 (Remember Magnitudes are based on a logarithmic scale. That means for each whole number higher, the amplitude of the ground motion recorded by a seismograph goes up ten times so magnitude 8 earthquake would result in ten times the ground shaking as a magnitude 7 earthquake)
For a short period earthquake, the report estimates that there would be minimal damage on Haida Gwaii similar to the damage from the 2012 earthquake with little or no damage on the BC North Coast.
A long duration, long period earthquake that lasted longer than one second and up to three seconds or longer “may effect taller structures and trigger ground failure (that is liquefaction and lateral shaking).” Kitimat would feel that earthquake with the worst shaking in parts of the District with what the report calls “sensitive soils.” Coastal islands would feel double the amount of shaking as would occur in Kitimat.
Model #2. A magnitude 7.2 Earthquake in Douglas Channel
The second model looked at an earthquake in Douglas Channel based on the “fault like structure” if a slip strike rupture occurred along the entire 60 kilometers of the so far unconfirmed fault, resulting in a 7.2 magnitude earthquake. There would be very strong shaking within 20 kilometers radius of the epicentre, with moderate to heavy damage” in the relatively uninhabited islands, major shaking in Hartley Bay, resulting in very strong to strong damage at Hartley Bay and strong to moderate damage in Kitimat.
That earthquake, however, would be felt across the entire province of British Columbia. The report notes:
The expected effects and impacts of such an earthquake would mimic those of the 1946 magnitude 7.3 Vancouver Island earthquake, which occurred slightly west of Courtney and Campbell River. Shaking due to the 1946 earthquake was felt as far as Prince Rupert, BC to the north and Portland, Oregon to the south. In addition to knocking down 75 per cent of the chimneys in the local area, much of the earthquake-related damage was due to landslides, slumping and liquefaction
Model #3 A magnitude 6.3 Earthquake near Terrace
On May 11, 1973, a magnitude 4.7 shallow earthquake took place about 20 kilometers south west of Terrace, on the south side of the Skeena roughly across from the Shames mountain area. The earthquake was felt up to 120 kilometers away. The report says “The event has not been associated with any geologic features in the area and little is known about its rupture process.” The model estimated the results of a larger earthquake 6.3 magnitude in the same area. The model showed there would be strong to very strong shaking in Terrace, light to moderate shaking in Kitimat and light damage elsewhere in the BC North Coast. Most of the damage would be concentrated in a 20 kilometer zone around the epicentre.
The cause of the two failures is still unknown but the report says “their proximity to a nearby unmapped fault-like structure suggests that the slides could have been triggered by strong ground shaking from rupture along this structure.”
Another factor was the two well-known landslides occurred in the 1970’s in the Kitimat Arm which generated tsunamis but fortunately they occurred at low tide which decreased the impact. On October 17, 1974 a submarine slide generated a 2.8 metre tsunami. The following year on April 27, 1975, a slope failure on the northeast side of Kitimat Arm (which overlapped the 1974 failure area) displaced an estimated upper limit of 26,000,000 cubic metres of material.
“Watermark observations in Kitamaat Village estimated that the tsunami generated by this slide was up to 8.2 metres high.” The report says that while the trigger of the first event is unknown; the latter event coincided with nearby construction at that time. Modelling of the 1975 slide estimates that given the right conditions the generated tsunami waves could have been as high as 11 metres.
The report also notes that numerous landslides have also been mapped by the BC Department of Forestry in an attempt to improve safety measures for forestry workers.
The report says “The culmination of these studies brings awareness to the significant natural hazards present in the fragile coastal environment of the Coast Ranges.”
Another factor is the geology of the BC coast. The granitic mountains have rugged, steep slopes dissected by an intricate fjord system and dotted with islands of lower elevation. At lower elevations the land is covered by wet, coastal hemlock forests, which could be vulnerable to ground failures whereas higher elevations are characterized by barren rock or mountain hemlock subalpine.
The District of Kitimat said it has “not directly studied these issues but we are aware of potential hazards.” The development department has been advised of potential issues and site concerns.
A spokesperson for Terrace mayor Carol Leclerc told Northwest Coast Energy News in an e-mail. “I have reviewed it and distributed it to the relevant department heads. We are aware that historically Terrace has been at risk for experiencing seismic activity due to its location.”
The District of Kitimat did cooperate with National Resources in finding a location for their recently installed seismic equipment.
At Harley Bay, Gitga’at First Nation CEO Ellen Torng said the Gitga’at have been “ working with NRCan on their research in the Douglas Channel and in Hawksbury. NRC has been meeting with First Nations along the coast and have conducted community sessions on their research.
“We hosted one community session here in Hartley Bay and have regular updates from their technical team when they are in the area,” Torng said.
In addition, the District of Kitimat told Northwest Coast Energy News that Community Planning & Development department also provided local land information to geoscientists in the years leading up an international study called Batholiths on land in 2009.
Batholiths are large zones of molten rock that have solidified in the earth’s crust and are believed to play a key role in the formation and growth of continents. The Coast Mountain Range has a large concentration of batholiths, which means Kitimat was an excellent place to study the earth’s crust.
The project, which involved more than 50 scientists from nine Canadian and American universities, was set up to examine how mountain belts form and change over time and why continental mountain ranges are made of granite not basalt. Seismic imaging of the crust and mantle below the mountains required deploying thousands of seismic sensors and recorders, and recorded responses to several man-made detonations. Field work was completed in July 2009, and several scientific papers and dissertations have followed.
The Heiltsuk Nation was unable to respond to a request for comment due to the ongoing crisis from the sinking of the tug Nathan E. Stewart and the resulting spill of diesel fuel and other contaminants near Bella Bella.
Not felt except by a very few under especially favorable conditions.
Felt only by a few persons at rest,especially on upper floors of buildings.
Felt quite noticeably by persons indoors, especially on upper floors of buildings. Many people do not recognize it as an earthquake. Standing motor cars may rock slightly. Vibrations similar to the passing of a truck. Duration estimated.
Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.
Felt by nearly everyone; many awakened. Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.
Felt by all, many frightened. Some heavy furniture moved; a few instances of fallen plaster. Damage slight.
Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable damage in poorly built or badly designed structures; some chimneys broken.
Damage slight in specially designed structures; considerable damage in ordinary substantial buildings with partial collapse. Damage great in poorly built structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned.
Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb. Damage great in substantial buildings, with partial collapse. Buildings shifted off foundations.
Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations. Rails bent.
The Ice Age First Nations in the interior of Alaska relied more heavily on salmon and freshwater fish in their diets than previously thought, according to a new study from the University of Alaska Fairbanks.
First Nations of the Pacific Coast have always recognized the value of the salmon. Archaeologists have used new techniques to date the remains of salmon found in hearths back more than 11,000 years. The results now offer a more complex picture of Alaska’s ice age residents, who were previously thought to have a diet dominated by terrestrial mammals such as mammoths, bison and elk.
A team of researchers made the discovery after taking samples from 17 prehistoric hearths along the Tanana River, then analyzed stable isotopes and lipid residues to identify fish remains at multiple locations.
The project also found the earliest evidence of human use of anadromous salmon in the Americas, dating back at least 11,800 years.
The results of the study were published today in the Proceedings of the National Academy of Sciences.
DNA analysis of chum salmon bones from the same site on the Tanana River had previously confirmed that fish were part of the local indigenous diet as far back as 11,500 years ago. But fragile fish bones rarely survive for scientists to analyze, so the team used sophisticated geochemistry analyses to estimate the amount of salmon, freshwater and terrestrial resources ancient people ate.
A team led by UAF postdoctoral researcher Kyungcheol Choy analyzed stable isotopes and lipid residues, searching for signatures specific to anadromous fish. The effort demonstrated that dietary practices of hunter-gatherers could be recorded at sites where animal remains hadn’t been preserved.
“It’s quite new in the archaeology field,” Choy said. “There’s a lot in these mixtures that’s hard to detect in other ways.”
Ben Potter, a professor of anthropology at UAF and co-author of the study, said the findings suggest a more systematic use of salmon than DNA testing alone could confirm.
“This is a different kind of strategy,” Potter said. “It fleshes out our understanding of these people in a way that we didn’t have before.”
The study required cooperation between UAF’s Department of Anthropology and the Institute of Northern Engineering’s Alaska Stable Isotope Facility to locate and interpret the presence of salmon remains at the sites. Potter said the process could be a template for how a diverse team of researchers can work together to overcome a scientific obstacle.
“It’s an awesome look at how we can merge disciplines to answer a question,” he said.
With climate change, the oceans are becoming more acid and that is a threat to the dungeness crab, according to a study by the US National Oceanic and Atmospheric Administration.
The study says ocean acidification expected to accompany climate change may slow development and reduce survival of the larval stages of Dungeness crab.
The dungeness crab is a key component of the Northwest marine ecosystem and vital to fishery revenue from Oregon to Alaska.
The research by NOAA Fisheries’ Northwest Fisheries Science Center in Seattle indicates that the declining pH anticipated in Puget Sound could jeopardize populations of Dungeness crab and put the fishery at risk. The study was recently published in the journal Marine Biology.
Ocean acidification occurs as the ocean absorbs carbon dioxide from the combustion of fossil fuels. Average ocean surface pH is expected to drop to about 7.8 off the West Coast by 2050, and could drop further during coastal upwelling periods.
Dungeness crab is the highest revenue fishery in Washington and Oregon, and the second most valuable in California, although the fishery was recently closed in some areas because of a harmful algal bloom. The Dungeness crab harvest in 2014 was worth more than $80 million in Washington, $48 million in Oregon and nearly $67 million in California
“I have great faith in the resiliency of nature, but I am concerned,” said Jason Miller, lead author of the research, which was part of his dissertation. “Crab larvae in our research were three times more likely to die when exposed to a pH that can already be found in Puget Sound, our own back yard, today.”
Scientists collected eggs from Dungeness crabs in Puget Sound and placed them in tanks at the NWFSC’s Montlake Research Laboratory. The tanks held seawater with a range of pH levels reflecting current conditions as well as the lower pH occasionally encountered in Puget Sound when deep water wells up near the surface. Larvae also went into tanks with the even lower-pH conditions expected with ocean acidification.
“The question was whether the lower pH we can expect to see in Puget Sound interferes with development of the next generation of Dungeness crab,” said Paul McElhany, a NOAA Fisheries research scientist and senior author of the paper. “Clearly the answer is yes. Now the question is, how does that play out in terms of affecting their life cycle and populations overall?”
Larvae hatched at the same rate regardless of pH, but those at lower pH took longer to hatch and progressed through their larval stages more slowly. Scientists suggested that the lower pH may reduce the metabolic rate of embryos. That could extend their vulnerable larval period, or could jeopardize the timing of their development in relation to key food sources, researchers suggested.
Larval survival also dropped by more than half at lower pH. At pH 8.0, roughly equivalent to seawater today, 58 percent of the crab larvae – called zoeae – survived for 45 days. At pH 7.5, which sometimes occurs in Puget Sound now, survival was 14 percent. At pH 7.1, which is expected to roughly approximate the pH of water upwelling on the West Coast with ocean acidification, zoeae survival remained low at 21 percent.
“Areas of greatest vulnerability will likely be where deep waters, naturally low in pH, meet acidified surface waters,” such as areas of coastal upwelling along the West Coast and in estuary environments such Hood Canal, the new study predicts.
Scientists have identified a new species of a strange marine mammal group that lived on the Pacific Coast between 33 million years ago and 10 million years ago. The new specimens — from at least four individuals — were recovered from Unalaska, in theAleutians.
The Desmostylians, unlike other marine mammals species alive today — such as whales, seals and sea cows –are extinct. The researchers call them “desmos” for short. Unlike whales and seals, but like manatees, desmos were vegetarians
The desmos are found from Baja, California, up along the west coast of North America, around the Alaska Peninsula, the storm-battered Aleutian Islands, to Russia’s Kamchatka Peninsula and Sakhalin Island, to the Japanese islands
Their strange columnar teeth and odd style of eating don’t occur in any other mammal. They rooted around coastlines, ripping up vegetation, such as marine algae, sea grass and other near-shore plants.
The new species, 23 million years old was a big, hippo-sized animal with a long snout and tusks, It has a unique tooth and jaw structure that indicates it was not only a vegetarian, but literally sucked vegetation from shorelines like a vacuum cleaner, said vertebrate paleontologist and study co-author Louis L. Jacobs, Southern Methodist University, Dallas.
They probably swam like polar bears, using their strong front limbs to power along. On land, they would have had the lumbering gait of a sloth.
A large, stocky-limbed mammal, desmos’ modern relatives remain a mystery. Scientists have previously linked the animals perhaps to manatees, horses or elephants. Adult desmostylians were large enough to be relatively safe from predators.
The identification of a new species belonging to Desmostylia has intensified the rare animal’s brief mysterious journey through prehistoric time, according to the new study.
While alive, the newly discovered creatures lived in what is now Unalaska’s Dutch Harbor.
“The new animal — when compared to one of a different species from Japan — made us realize that desmos do not chew like any other animal,” said Jacobs, a professor of earth sciences. “They clench their teeth, root up plants and suck them in.”
To eat, the animals buttressed their lower jaw with their teeth against the upper jaw, and used the powerful muscles that attached there, along with the shape of the roof of their mouth, to suction-feed vegetation from coastal bottoms. Big muscles in the neck would help to power their tusks, and big muscles in the throat would help with suction.
“No other mammal eats like that,” Jacobs said. “The enamel rings on the teeth show wear and polish, but they don’t reveal consistent patterns related to habitual chewing motions.”
The new specimens also represent a new genus — meaning desmostylians in the same family diverged from one anoher in key physical characteristics, particularly the tooth and jaw structure, said Jacobs, who is one of 10 scientists collaborating on the research.
Discovery of a new genus and species indicates the desmostylian group was larger and more diverse than previously known, said paleontologist and co-author Anthony Fiorillo, vice president of research and collections and chief curator at the Perot Museum of Nature and Science, Dallas, and an adjunct research professor at SMU.
“Our new study shows that though this group of strange and extinct mammals was short-lived, it was a successful group with greater biodiversity than had been previously realized,” Fiorillo said.
Compared to other mammals, desmos were latecomers and didn’t appear on earth until fairly recently — 33 million years ago. Also unusual for mammals, they survived a mere 23 million years, dying out 10 million years ago.
The research was funded by the Perot Museum of Nature and Science, U.S. National Park Service – Alaska Region Office, and SMU’s Institute for the Study of Earth and Man.
The newest desmo made its home on Unalaska Island, the farthest north of any occurrence of the group, which only lived along the shores of the North Pacific.
“That’s the only place they’re known in the world,” Jacobs said. The Unalaska fossils represent at least four individuals, and one is a baby.
“The baby tells us they had a breeding population up there,” Jacobs said. “They must have stayed in sheltered areas to protect the young from surf and currents.”
In addition, “the baby also tells us that this area along the Alaska coast was biologically productive enough to make it a good place for raising a family,” said Fiorillo.
Just as cattle assemble in a herd, and a group of fish is a school, multiple desmostylians constitute a “troll” — a designation selected by Jacobs to honor Alaskan Ray Troll, the artist who has depicted desmos most.
The first Unalaska fossils were discovered in the 1950s in a rock quarry during U.S. Geological Survey mapping.
Others found more recently were on display at the Ounalashka Corporation headquarters. Those specimens were offered to Fiorillo and Jacobs for study after Fiorillo gave a public presentation to the community on his work in Alaska.
“The fruits of that lecture were that it started the networking with the community, which in turn led us to a small, but very important collection of fossils that had been unearthed in the town when they built a school a few years earlier,” Fiorillo said. “The fossils were shipped to the Perot Museum of Nature and Science for preparation in our lab and those fossils are the basis for our work now.”
From there, the researchers discovered that the fossils were a new genus and species.
The authors report their discoveries in a special volume of the international paleobiology journal, Historical Biology. The article published online Oct. 1 at http://bit.ly/1PQAHZJ
The researchers named the new mammal Ounalashkastylus tomidai. “Ounalashka,” means “near the peninsula” in the Aleut language of the indigenous people of the Aleutian Islands.
“Stylus” is from the Latin for “column” and refers to the shape of cusps in the teeth.
“Tomida” honors distinguished Japanese vertebrate paleontologist Yukimitsu Tomida.
The article appears in a special volume of Historical Biology to honor the career accomplishments of Tomida upon his retirement from the Department of Geology and Paleontology in Tokyo’s National Museum of Nature and Science.
In addition to Jacobs, Fiorillo and Polcyn, other authors were Yosuke Nishida, SMU; Yuri Kimura, Smithsonian Institution and the Tokyo Museum; Kentaro Chiba, University of Toronto; Yoshitsugu Kobayashi, Hokkaido University Museum, Naoki Kohno, National Museum of Nature and Science; and Kohei Tanaka, University of Calgary.
The Historical Biology article is titled “A new desmostylian mammal from Unalaska (USA) and the robust Sanjussen jaw from Hokkaido (Japan), with comments on feeding in derived desmostylids” and appears in the special issue “Contributions to vertebrate palaeontology in honour of Yukimitsu Tomida.”
The study shows that embryonic salmon and herring exposed to very low levels of crude oil can develop hidden heart defects that compromise their later survival.
That means that the Exxon Valdez spill on March 24, 1989 may have had much greater impacts on spawning fish than previously recognized, according to the study published in Nature’s online journal Scientific ReportsVery low embyronic crude oil exposures cause lasting defects in salmon and herring.
“These juvenile fish on the outside look completely normal, but their hearts are not functioning properly and that translates directly into reduced swimming ability and reduced survival,” said John Incardona, a research toxicologist at NOAA Fisheries’ Northwest Fisheries Science Center (NWFSC) in Seattle. “In terms of impacts to shore-spawning fish, the oil spill likely had a much bigger footprint than anyone realized.”
Previous research has shown that crude oil disrupts the contraction of the fish heart muscle cells. Embryonic fish exposed to trace levels of crude oil grow into juveniles with abnormal hearts and reduced cardiorespiratory function.
“With this very early impact on the heart, you end up with an animal that just can’t pump blood through its body as well, which means it can’t swim as well to capture food, form schools, or migrate,” said Mark Carls, toxicologist at the Alaska Fisheries Science Center. “Crude oil is changing basic physiology, or what makes a fish a fish.”
The research builds on earlier work by the Auke Bay Laboratories, part of NOAA Fisheries’ Alaska Fisheries Science Center, which found much reduced survival of pink salmon exposed as embryos to polycyclic aromatic hydrocarbons (PAH) from crude oil.
“Our findings are changing the picture in terms of assessing the risk and the potential impacts of oil spills,” said Nat Scholz, leader of the NWFSC’s ecotoxicology program and a coauthor of the new study. “We now know the developing fish heart is exquisitely sensitive to crude oil toxicity, and that subtle changes in heart formation can have delayed but important consequences for first-year survival, which in turn determines the long-term abundance of wild fish populations.”
The Exxon Valdez spill was the largest in U.S. history, with extensive oiling of shoreline spawning habitats for Pacific herring and pink salmon, the two most important commercial fish species in Prince William Sound.
Herring larvae sampled in proximity to oil were visibly abnormal, and mortality rates were higher for pink salmon embryos at oil spill sites than unaffected regions.
The herring fishery collapsed three to four years after the spill, when the herring spawned in oiled areas reached reproductive maturity.
The paper notes that the contribution of the spill to the herring population collapse, if any, was never determined and remains controversial.
Other studies, however, tend to confirm the findings, including heart problems for fish exposed to the Gulf of Mexico Deepwater Horizon spill and even fish exposed to naturally occurring oil seeps.
The new findings suggest that the delayed effects of the spill may have been important contributors to the declines.
Scientists from the Northwest Fisheries Science Center and Alaska Fisheries Science Center temporarily exposed embryonic salmon and herring to low levels of crude oil from the North Slope of Alaska and found that both absorbed chemicals at similar concentrations in their tissues. The embryos were then transferred to clean seawater and raised as juvenile fish for seven to eight months.
Few of the exposed embryos were outwardly abnormal in any way. However, closer examination of the fish revealed subtle defects that could reduce their long-term survival.
Juvenile salmon exposed to oil grew more slowly, with those exposed to the highest concentrations growing the slowest. For salmon, early survival in the ocean is strongly influenced by juvenile growth, with smaller fish suffering higher loss to predators.
Scientists used swimming speed as a measure of cardiorespiratory performance and found that fish exposed to the highest concentrations of oil swam the slowest. Slower swimming is an indication of reduced aerobic capacity and cardiac output, and likely makes fish easier targets for predators.
Exposure to oil as embryos altered the structural development of the hearts of juvenile fish, potentially reducing their fitness and swimming ability. Poor swimming and cardiac fitness is also a factor in disease resistance.
Earlier studies on the ecosystem-scale crash of the Prince William Sound herring population several years after the Exxon Valdez spill were based on higher levels of exposure to the oil. The new study shows that that cardiac injury occurs in normal-appearing fish that survive even lower level exposures.
The scientists reviewed data on measured oil concentrations in surface water samples collected in Prince William Sound after the oil spill and during the 1989 herring spawning season. Most of the 233 samples contained less oil than was believed to be toxic to herring at the time, based on visible gross developmental abnormalities. However, nearly all of the samples contained oil at or above concentrations shown in the new study to alter heart development.
If the Exxon Valdez spill impacted heart development among a large majority of fish that were spawned in proximity to oiled shorelines, the subsequent losses of juveniles to delayed mortality would have left fewer adults to join the population. Although not direct proof, this provides a plausible explanation for the collapse of the Prince William Sound herring stock four years later, when fish spawned during the oil spill would have matured.
The study concludes that the impacts of the Exxon Valdez spill on near shore spawning populations of fish are likely to have been considerably underestimated in terms of both the geographic extent of affected habitat and the lingering toxicity of low levels of oil. The findings will likely contribute to more accurate assessments of the impacts of future oil spills, Incardona said. “Now we have a much better idea of what we should be looking for,” he said.
That means, according to the study “that the impacts of the Exxon Valdez oil spill on populations of near shore spawning fish are likely to have been considerably underestimated, in term of both the geographic extent of affected habitats and the lingering toxicity of low levels of residual oil.”
The report calls for more studies of the sensitivity of the developing fish heart since the vulnerability “also has implications for other pollution sources in marine ecosystems, including increasing maritime vessel traffic and expanding land-based urban runoff.”
Scientific studies after the Exxon Valdez spill indicated that the vast majority of species recovered following the spill and that functioning ecosystems, similar to those existing pre-spill, were established.
Species for which recovery is not fully apparent, such as Pacific herring, killer whales, and pigeon guillemots, appear to have been affected by other environmental factors or human influences not associated with the oil spill. Insufficient pre-spill baseline data on these species contributed to difficulties in determining the extent of spill effects.
Based on the evidence, the Panel finds that natural recovery of the aquatic environment after an oil spill is likely to be the primary recovery mechanism, particularly for marine spills. Both freshwater and marine ecosystem recovery is further mitigated where cleanup is possible, effective, and beneficial to the environment.
Natural processes that degrade oil would begin immediately following a spill. Although residual oil could remain buried in sediments for years, the Panel finds that toxicity associated with that oil would decline over time and would not cause widespread, long-term impacts.
Ninety-seven years ago, long before the townsite was founded in the 1950s, Kitimat was to play a short, now forgotten and unlucky role in the First World War with the launch of a vessel in New Westminster called the War Kitimat as one of the many emergency new ships commissioned by the British government to replace vessels lost to Germany’s unrestricted submarine warfare that was sinking convoys taking vital supplies across the Atlantic.
(Note: The ship may not have been the Valley’s only role in the First World War. I have been told by Haisla members that it is believed that a couple of men from the Haisla Nation may have served in the armed forces during WWI. However, no one I have contacted, so far, has been able to confirm that information. If anyone can confirm, this story will be updated).
During the First World War, over nine million gross tons of British ships were lost due to enemy action, both submarines and surface raiders. The worst losses came in the three months ending June 1917 when over 1.4 million gross tons were sunk.
In December, 1916, the Prime Minister David Lloyd George’s British Government appointed a “shipping controller” to manage a worldwide shipbuilding program to replace the lost vessels, to be built quickly, efficiently and to a series of standard designs. Although the vessels were often different, they were called “standard ships.” It was the Great War’s equivalent of the Liberty Ships built during the Second World War.
Many of the orders were placed with Canadian companies, others with the Japanese shipyards and British owned or controlled shipyards in Hong Kong and Shanghai. Canada created or contracted 19 emergency shipbuilders which built 137 cargo ships and 15 trawler/minesweepers. Some of these yards were purpose-built, others were repair yards that were converted to construction yards; seven were in BC, nine were in Ontario and Quebec, and three were in the Maritimes.
Orders were also placed with shipyards in the United States, but when the Americans entered the war in 1917, those ships were requisitioned by the U.S. Government.
All the ships’ names were given the prefix “War” no matter where they were built in the world.
The Canadians built both steel hulled and wooden hulled cargo vessels, including the War Kitimat, as well as yachts and sailing yachts (which likely became the war time “trawlers”). The British built 12 different types of “dry cargo” vessels, five types of “coasters” plus tankers. The United States also built wooden hulled cargo vessels (slightly larger than the Canadian versions) and various types of steel hull cargo ships.
The government of France also contracted Canadian shipyards for its own vessel building program.
In Canada, the BC Marine Railway Company was one of the prime contractors, and the job of building four ships was awarded to the New Westminster Shipbuilding & Engineering on Poplar Island, which can be seen today from New West’s Esplanade at Westminster Quay.
The First Nations of the area had used the island for generations and in 1871 the island was designated an Indian Reserve. During the small pox epidemic of 1889, with many members of the Vancouver area First Nations struck down by the disease, a hospital was built on the island. It is believed that many of those who died of smallpox were buried there. Because of the association with disease and death the island was abandoned until 1917, when the war time necessity meant a shipyard was built on the island.
New Westminster Shipbuilding had the job of constructing four “war” class wooden hulled freighters, 2300 gross tonnes, 3300 dead weight tonnes, 250 feet long with a beam of 43.5 feet, with 322 nominal horse power triple reciprocating steam engines powered by two water tube boilers, turning a single screw capable of ten knots.
The company built four ships, the War Comox, War Edensaw, War Kitimat and War Ewen. The War Comox was first launched in April, 1918, but completion was held up as the shipyard waited for equipment from suppliers. That led to pressure to build, launch and complete the War Edensaw, which was launched in June 1918, and the War Kitimat, which was launched on Sunday, August 18, 1918.
The War Kitimat immediately ran into trouble. According to the Times Colonist, right after launch the War Kitimat ran aground off New Westminster and had to be lifted off the Fraser river bed by using jacks until was raised enough so that tugs could attach lines and tow it to deep water. About a week later, the War Kitimat was towed to Victoria for repairs and further fitting out (possibly to the Foundation Company shipyard which was also building five of the war class vessels. Foundation is now Seaspan’s Point Hope Marine)
The War Kitimat did make at least one voyage to Great Britain, but by the time it arrived, the war was coming to a close. After the Armistice on November 11, 1918, the ships were no longer needed and the British government sold most of them to shipping companies. (All the ships were UK registry, not Canadian)
In 1919, the War Kitimat was sold to the Lloyd Royal Belge S.A. line of Antwerp, Belgium and renamed the Serbier.
How the ship came to be named War Kitimat isn’t certain. It was probably named after the Kitimat River since other vessels in the War category were named Skeena, Stikine, Babine, Niagara, Ottawa (others were named for cities like Halifax or Toronto).
The Belgian shipping company did not give up on the name Serbier. It purchased another US-built War cargo ship, first named the War Hound by the British. After the US entered WWI in 1917 and took over the building there it became the Lake Huron, a US Navy Transportation Service mine carrier. From later in 1920, Royal Belge operated the new Serbier until 1924, when it passed through French, Norwegian, Danish and then as the Advance, Finnish ownership. The Advance was seized in Panama by the United States in 1941 and renamed the Trojan. After the Second World War, the US returned the ship to Finland. It sailed as the Advance until it was sold a Greek shipping company in 1965 and scrapped at Piraeus in 1966.
Of the ships under British control, 821 ships were ordered by the UK shipping board and 416 were completed. Fourteen were lost to enemy action. The remaining orders were cancelled but often completed by the shipyards.
Many of the “war” or “standard” ships passed through various owners.
During the Second World War many played their original role and took part in the convoys that crossed the Atlantic. Many were sunk during those crossings. Others, sold to growing Japanese shipping interests in the 1920s and 1930s, were sunk by US destroyers and submarines. Others like the War Hound /Serbier survived to the 1950s and 1960s.
Of the War Kitimat’s sister ships built in New Westminster, the War Comox was sold to an Italian company, renamed the Guidatta and scrapped at Genoa in 1925, The War Ewen was sold to a German company, renamed the Etienne Marcel and scrapped in Germany in 1925. The War Edensaw, under the original name, was carrying Admiralty stores from Constantinople to Malta, when it caught fire on June 25, 1919 and sank 94 nautical miles east of the St. Elmo Lighthouse on Malta.
As for Poplar Island, it was zoned for industrial use but no one could come up with ideas for how to use the island. New Westminster sold the island to Rayonier Canada in 1945, where it became an anchorage for log booms on the Fraser River. The successor company, Western Forest Products sold it back to New Westminster in 1995, The island is still a wilderness area in the middle of urban Vancouver and subject to treaty and land claims negotiations with the area’s First Nations.
Editor’s Note: Up until now Kitimat has not had a reason, unlike other communities, to mark Canada’s role in the First World War. We suggest that should the District of Kitimat choose to do so either this year or in the next three years, August 18, the date of the launch of the War Kitimat might be an appropriate date, in addition to Remembrance Day on November 11.
The United States Coast Guard says it is monitoring repairs aboard the liquid natural gas carrier Excel in Homer, Alaska, Friday, May 1.
According to a news release from Coast Guard Sector Anchorage, USCG issued an order for the vessel to remain anchored in Kachemak Bay near Homer after the 908-foot, Belgium-flagged vessel experienced a loss of propulsion due to a failed engineering gasket while inbound to Cook Inlet Monday.
The Excel was bound for the existing LNG facility, the Kenai LNG Plant, located in Nikiski on the Kenai Peninsula, in Alaska. The state of Alaska is planning to expand the LNG facilities there, and that site is a potential rival for British Columbia’s LNG export plans.
The Coast Guard release says:
The Excel was examined by Coast Guard inspectors from Marine Safety Detachment Homer, Tuesday, who conducted a Port State Control annual exam and verified the engineering gasket was replaced.
While preparing to get underway Wednesday, the vessel experienced an automated engineering casualty and canceled its voyage until a Bureau Veritas (BV) classification surveyor could arrive and verify the engineering casualty was fully resolved. After arriving aboard the vessel, the class surveyor directed the vessel’s crew to test the automated engineering system and deduced that the casualty was a product of a faulty engine order telegraph; a device used on ships for the pilot on the bridge to order engineers in the engine room to power the vessel at a certain desired speed. Coast Guard Sector Anchorage issued another order for the vessel to remain in Kachemak Bay.
Friday, the vessel was allowed to continue sailing to her destination at the ConocoPhilips LNG plant in Nikiski after additional safety measures were implemented. As part of the safety measures, the tug Stellar Wind escorted the vessel from Kachemack Bay to Nikiski and a second tug, the Glacier Wind, stood by in Nikiski to assist with docking operations.
The Excel completed her voyage and safely moored at the ConocoPhilips pier in Nikiski at approximately noon Friday where it remains until permanent repairs are verified by the class surveyor and Coast Guard inspectors.
“Ensuring safe navigation in Western Alaska, particularly in Cook Inlet, is one of my highest priorities,” said Capt. Paul Mehler III. “Our crews worked closely with the Southwest Alaska Pilots Association, the class surveyor and towing vessel industry to coordinate a safe and secure transit of the Excel from Kachemak Bay to Nikiski. The weather was also in our favor with clear skies, light winds, and steady ebb tide during the transit in Cook Inlet.”
The LNG export plant at Nikiski was built in 1969 by Phillips Petroleum and Marathon Oil. Phillips later merged with Conoco and subsequently purchased Marathon’s 30 per cent share. The Nikiski plant sent LNG shipments to Japan from 1969 to 2010 under long-term contracts with Tokyo Gas and Tokyo Electric, when the contracts expired.
In 2011 ConocoPhillips announced that it would be ceasing LNG exports from Kenai and preserving the plant for potential future use.
With the LNG rush, market conditions changed and the the plant resumed making LNG in early 2012 and exported four cargoes to Asian customers over the course of that year.
In March 2013, the export licence expired and the LNG plant was put on standby. As interest in LNG grew, and at the urging of the state of Alaska, in December 2013 ConocoPhillips Alaska applied to resume LNG exports and the U.S. Department of Energy approved the resumption in April, 2014. ConocoPhillips says it received authorization to export a total of 40 BCF of liquefied natural gas over a two-year period from 2014 through 2016.
The Alaska LNG project is “a proposed $45 to $65 billion liquefied natural gas export project – it would be the largest single investment in Alaska history. The project has the potential to create between 9,000 and 15,000 jobs during the design and construction phases; plus approximately 1,000 jobs for continued operations. In addition to generating billions of dollars in revenue for Alaska, the project will provide access to natural gas for Alaskans.” The project’s participants are the Alaska Gasline Development Corporation (AGDC) and affiliates of TransCanada, BP, ConocoPhillips, and ExxonMobil.
A “devastating megathrust earthquake” could hit Haida Gwaii sometime in the future, according to Canadian and US studies carried out after the magnitude 7.8 earthquake off Haida Gwaii on Oct. 27, 2012 and the 7.5 magnitude quake off Craig, Alaska, a few weeks later on Jan. 5, 2013.
The 2004 Indian Ocean earthquake and the 2011 Tōhoku earthquake in Japan, both accompanied by major tsunamis are recent examples of “great” (higher than magnitude 8.0) megathrust earthquakes. Most of the concern on the west coast has been the likelihood of a megathrust earthquake on the Cascadia Fault on the Juan de Fuca plate that stretches from northern California to the middle of Vancouver Island.
The 2012 Haida Gwaii main shock was the second largest seismic event in Canada since the establishment of a modern seismograph network. The first was the 1949 Haida Gwaii/Queen Charlotte earthquake with a magnitude of 8.1 That 1949 Haida Gwaii earthquake was a strike-slip event, where the plates move side-to-side, similar to the 1906 San Francisco earthquake and other quakes on the San Andreas Fault in California.
The 2012 Haida Gwaii earthquake is characterized in the studies as a “mini-megathrust” event, where part of the crust is pushed upward, meaning that a larger megathrust could have much more destructive consequences from both the earthquake and a possible tsunami.
Complex system of faults
The new studies show that the Pacific and North America plate boundary off the coast of British Columbia and southeastern Alaska creates a system of faults capable of producing very large earthquakes. The scientists conclude that while the two earthquakes in 2012 and 2013 released strain built up over years on the tectonic plates, those events did not release strain along the Queen Charlotte Fault off the west coast of Haida Gwaii. That means the fault remains the likely source of a future large earthquake.
A special issue of the Bulletin of the Seismological Society of America (BSSA), released Monday, April 6, 2015, contains 19 scientific and technical papers, outlining the results of the work carried out over the past two years.
The team estimated the rupture dimension of the 2012 Haida Gwaii earthquake to be about 120 kilometres long at a depth of about 30 kilometres.
The Craig earthquake ruptured the Queen Charlotte fault over a distance of more than 100 kilometres and at a depth of about 20 kilometres.
The two areas are joined in what is called the Queen Charlotte Fairweather Fault System. To the south the Queen Charlotte Fault also interacts with the Juan de Fuca plate that stretches from Vancouver Island to northern California.
“The study of these two quakes revealed rich details about the interaction between the Pacific and North America Plates, advancing our understanding of the seismic hazard for the region,” said Thomas James, research scientist at Geological Survey of Canada.
Two faults off Haida Gwaii
The studies conclude that the interaction between the plates off Haida Gwaii is much more complex than previously believed. Before the 2012 earthquake, the Queen Charlotte Fault, a strike-slip fault similar to the San Andreas Fault in California, was believed to be the dominating tectonic structure in the area. The 2012 tremor confirmed the existence of a previously suspected thrust fault beneath what is called the “Queen Charlotte Terrace,” to the west of the Queen Charlotte Fault, where the Pacific plate is sliding at a low angle below the North American plate.
The Queen Charlotte Terrace, which is about a kilometre below the surface of the ocean, is built up of layers of sediment, several kilometres thick, scraped off the oceanic plate as it subducts under the North American plate. It may also include some fragments of oceanic crust. For most of the terrace, it is “present as a clearly defined linear feature,” but the study adds: “north of about 53.5° N, a complex pattern of ridges and valleys appears.”
The earthquake was “essentially a mini-megathrust earthquake along the dipping plate interface of a subduction system,” one of the scientific papers says. The epicenter of the Haida Gwaii main shock was located about five kilometres landward (northeast) of the Queen Charlotte Fault. That probably means that the rupture was near the bottom of the locked plates, where the plate motion’s side to side movement is also thrusting downward. Significant aftershocks appeared to cluster on the periphery of the main rupture zone with most of the aftershocks occurring seaward to the west.
The scientists used GPS observations of crustal motion to locate the earthquake’s rupture offshore to the west of Haida Gwaii.
The situation off Haida Gwaii is complex because while the Pacific plate is converging with the North American plate at a rate of 15 to 20 millimetres a year, at the same time the two plates are slipping by each other toward the north northwest at angle of about 20 degrees at a rate of about 50 millimetres a year.
Honn Kao, a seismologist with the Geological Survey of Canada said, “This was an event the thrust interface of the plate boundary system, confirming that there is a subduction system in the Haida Gwaii area.
“The implication of a confirmed subduction zone is that in addition to the Queen Charlotte Fault, we now have another source which can produce devastating megathrust earthquakes in the area,” said Kao.
The study of the Haida Gwaii tremor looked at the causative faults, the rupture processes and depths of the main shock and sequence of strong aftershocks.
The Haida Gwaii earthquake generated a significant tsunami that left deposits indicating run-up exceeding 3 metres (maximum 13 metres) in a number of bays and inlets along about 230 kilometres along the west coast of Haida Gwaii. In Hawaii, a 0.8 metre wave was measured on a tide gauge.
In Queen Charlotte City perceptible shaking lasted for one and half to two minutes, with very strong shaking for about 30 seconds. The earthquake was felt as far away as Yukon Territory, Alberta, and Montana.
The study says “Damage was limited, in part owing to the sparse population, but also because of the seismic resistance of the generally low rise, wood-frame buildings on the islands. Felt intensities were at expected values close to the source zone, but regional intensities were smaller than predicted.”
The Haida Gwaii rupture also shook southeastern Alaska. The northwest direction of ground motion then may have influenced the timing of the Craig earthquake a few weeks later in January 2013. That earthquake occurred farther north in southeast Alaska, where relative plate motion is nearly parallel to the Queen Charlotte fault.
The Haida Gwaii aftershocks clustered around the periphery of the rupture zone, both on the seaward and landward side of the plate boundary and reflected what the study calls “normal faulting behavior–caused by the bending, extending or stretching of rock– rather than the thrust faulting of the main shock.” The pattern of aftershocks is similar to those observed after the 2011 Japanese megathrust earthquake.
“Our observations of normal faulting imply that the main shock of the Haida Gwaii earthquake dramatically altered the stress field in the rupture zone, especially in a neighboring region,” Kao said.
The distribution of aftershocks occurred to the north of a previously identified seismic gap where large earthquakes have not occurred in historic times. The gap is located to the south of the where 1949 magnitude 8.1 Queen Charlotte earthquake ruptured.
Though the Haida Gwaii earthquake may have activated some part of the Queen Charlotte Fault, Kao said, it was limited and did not relieve stress along the seismic gap.
The study concludes:
The Haida Gwaii event confirmed substantial seismic and tsunami hazard from large thrust events on the plate margin along the southern Queen Charlotte fault. It occurred where relatively young oceanic lithosphere under thrusts North America and in some ways is an analog for the much larger megathrust earthquakes known to occur on the Cascadia subduction zone to the south, where the young Juan de Fuca plate and other small plates subduct beneath North America. The Haida Gwaii earthquake had a complex pattern of main shock rupture and aftershocks and a large tsunami.
Further study needed
The Geological Survey of Canada plans further studies to understand the formations off Haida Gwaii.
One question to ask is if there are any records of major earthquake events in the past history of Haida Gwaii. The study notes that the impact of the tsunami was relatively minor “in this region with steep rocky coastlines.” That means there are limited sources of coastal sediments that can be checked for past events. It adds: “Low-elevation lakes, ponds, and bogs may offer the best opportunities for paleotsunami studies” warning that large earthquakes in the past that produced tsunamis may have left little evidence in the “paleoseismic record of Haida Gwaii and similar settings worldwide.”
Megathrust earthquakes occur at subduction zones at destructive plate boundaries where one tectonic plate is subducted (forced underneath) by another. These interplate earthquakes are the planet’s most powerful, with moment magnitudes that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes. During the rupture, one side of the fault is pushed upwards relative to the other, and it is this type of movement that is known as thrust. The displacement of the ocean in a thrust can trigger a tsunami.
A transform fault is one where the motion is predominantly horizontal. Those faults end abruptly and are connected on both ends to other faults, ridges, or subduction zones. The best-known (and most destructive) are those on land at the margins of tectonic plates. Transform faults are the only type of strike-slip faults at plate boundaries show strike-slip or side-to-side in movement.
Queen Charlotte Terrace
The Queen Charlotte Terrace is a 25 kilometre wide zone of built up marine sediment immediately west of the active Queen Charlotte fault. The crust is about 12 kilometres thick at the terrace. On Haida Gwaii, the earth’s crust is 18 kilometres thick at the eastern edge. On the BC mainland the crust is in excess of 30 kilometres thick.
The 1949 Haida Gwaii quake was one of the largest in the recorded history of North America.
The largest known earthquake along the coast was the megathrust event on the Cascadia fault on January 26, 1700 where the Juan de Fuca plate ruptured for about 1,000 kilometres along from what is now northern California to Vancouver Island, estimated at magnitude 9.0. The dating is based on a tsunami that hit Japan that had no associated local earthquake as well studies of tree rings from the remains of trees downed in the tsunami.
The report mainly concerns the United States, where the race for LNG exports is as fierce as it is in Canada.
“Tens of billions of dollars in capital are targeted for the seven LNG export terminals currently granted licenses by the U.S. Department of Energy (DOE),” said Deepa Poduval, Principal Consultant with Black & Veatch’s management consulting business. “Infrastructure construction, real estate transactions and other services associated with these projects are expected to spur significant levels of economic activity throughout the value chain.”
As far as Canada is concerned, Poduval said, “proposed projects continue to suffer from regulatory and environmental delays, high costs and fiscal uncertainty that have hindered development on all but a couple of frontrunners.”
The report was based on experts surveyed by the company. Respondents were asked to select their expectation of the volume of natural gas that will be exported from the United States and Canada as LNG by 2020.
Nearly 37 percent of respondents said they believed exports would total more than 6 Bcf/d by 2020. In 2013, less than 25 percent of respondents expected exports at this level. In 2014, 60 percent of respondents said they expected LNG exports to be less than 10 Bcf/d by 2020. Less than 7 percent of respondents put the figure at more than 10 Bcf/d.
Poduval said that as less expensive U.S. gas becomes more viable, Asian buyers are increasingly pushing back on higher cost supplies from their suppliers in Asia, Australia and the Middle East, Poduval said.
This pushback is stalling some of the more expensive LNG projects in Canada, Australia and East Africa, with Asian buyers holding back on long-term purchase commitments from these projects in pursuit of more favorable price terms… One of the dangers for U.S. LNG exports continues to be that they could shrink the very price spread that makes them attractive.
Poduval said the first trains at Sabine Pass in Louisiana are expected to go online starting in the fourth quarter of 2015.
Poduval noted the announcement of the 30-year $400 billion agreement for Russia to supply natural gas to China via a new pipeline was considered by some as the “Holy Grail” of international natural gas agreements following stalemated negotiations for more than 10 years between the two countries.
The deal could provide much-needed market diversity for Russia, which exports 80 percent of its natural gas to an increasingly unfriendly Europe that is pursuing other sources of supply. In addition, Russia would potentially supplant some LNG demand from China by supplying about 3.5 Bcf/d of natural gas under this agreement.
Her report also says that an Alaska LNG pipeline project that has been on and off for the past 30 years is now in a pre-FEED (Front End Engineering and Design) stage.
If it goes ahead, the project, which would be the largest in North America, with a capital cost estimate of $45 billion to $65 billion, will bring gas from the North Slope along an 800-mile pipeline to south-central Alaska, where it will be liquefied for shipping to Asian markets.
“But the marketplace continues to be subject to geopolitical events and regional economics,” Poduval said.
Royal Dutch Shell has finally ditched plans for a new $US20 billion-plus liquefied natural gas project in Queensland,making it the latest casualty of the oil price slump.
Global chief executive Ben van Beurden said the proposed greenfield Arrow LNG project with PetroChina was “off the table”, while other ventures would be slowed as priority was given instead to Shell’s North American LNG projects.
“We are prioiritising North America LNG options in that timeframe, LNG Canada and Elba,” he explained, referring to Shell’s LNG export projects in western Canada and the US state of Georgia.
Shell is also a partner in the Woodside Petroleum-led Browse floating LNG project, the Sydney Morning Herald reported. Woodside recently announced it will buy Apache’s stake in the Chevron-led Kitimat LNG project. Shell says:
the timing for starting engineering and design had already been deferred by six months to mid-2015. While the Shell chief executive’s words place some uncertainty whether the oil major wants to proceed in that timeframe, the company has still listed Browse among final investment decision “choices” for the 2015-16 period.
The Douglas Channel project, which contemplates a floating LNG project at the old log sort half way between Kitimat harbour and the Chevron-led Kitimat LNG project at Bish Cove is a now partnership between EXMAR, “an independent Belgium-based company with 35 years’ experience in LNG shipping,” EDF Trading (“EDFT”) a subsidiary and wholesale market operator of Electricite de France S.A., an international energy company with over 39 million customers and AIJVLP, “a limited partnership between AltaGas Ltd. (“AltaGas”) and Idemitsu Kosan Co.,Ltd. (“Idemitsu”). Idemitsu is a Japan-based global leader in the supply of energy and petroleum. AltaGas is the parent company of Pacific Northern Gas which supplies consumers in Kitimat.
The news release says the “Consortium has also executed long-term lease agreements with the Haisla Nation regarding land and water tenure, and with Pacific Northern Gas Ltd. (PNG) for long-term pipeline capacity to supply gas.”