Special Report: New study identifies earthquake hazards for Hartley Bay, Bella Bella, Kitimat and Terrace

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.”

Geological Survey of Canada map showing parts of Canada that are prone to landslides. The BC North Coast study area is outlined by the rectangle. (Geological Survey of Canada)
Geological Survey of Canada map showing parts of Canada that are prone to landslides. The BC North Coast study area is outlined by the rectangle. (Geological Survey 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.”

New studies

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.

A Geological Survey of Canada map showing the BC North Coast region with earthquakes identified prior to and during recent studies. (Geological Survey of Canada)
A Geological Survey of Canada map showing the BC North Coast region with earthquakes identified prior to and during recent studies. (Geological Survey of Canada)

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

Detail of a map from the Geological Survey of Canada where the red line shows the 60 kilometre possible (still unconfirmed) fault line running from Gribbell Island to Princess Royal Island (Geological Survey of Canada)
Detail of a map from the Geological Survey of Canada where the red line shows the 60 kilometre possible (still unconfirmed) fault line running from Gribbell Island to Princess Royal Island (Geological Survey of Canada)

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.

CBC Television reported the earthquake caused a leak of toxic gas at the Alcan Aluminum plant at Jonquière, which was quickly contained. “There was no wind, we were basically lucky,” Alcan spokesman Jacques Dubac told CBC News at the time. 

Terrace earthquake

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.

Cascadia subduction zone (USGS)
Cascadia subduction zone (USGS)

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 Geological Survey Canada model for an 8.0 magnitude earthquake west of Haida Gwaii. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale (Geological Survey of Canada)
The Geological Survey Canada model for an 8.0 magnitude earthquake west of Haida Gwaii. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale.  The red polygon represents the area of possible rupture in the model with the star representing the epicentre. (Geological Survey of Canada)

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 Geological Survey Canada model for a 7/2 magnitude earthquake in the lower Douglas Channel. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale. The red star represents the possible epicentre. (Geological Survey of Canada)

The Geological Survey Canada model for a 7/2 magnitude earthquake in the lower Douglas Channel. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale. The red star represents the possible epicentre. (Geological Survey of Canada)

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

 The Geological Survey Canada model for an 6.3 magnitude earthquake southwest of Terrace. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale. The red polygon represents the area of possible rupture in the model with the star representing the epicentre. (Geological Survey of Canada)

The Geological Survey Canada model for an 6.3 magnitude earthquake southwest of Terrace. The possible damage is colour coded in the table below the map according to the Modified Mercalli Intensity Scale. The red polygon represents the area of possible rupture in the model with the star representing the epicentre. (Geological Survey of Canada)

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.

Motivation for study

It was not just potential industrial development that motivated the new studies. The discovery of that possible fault line in the lower Douglas Channel was also a factor. Studies between 2007 and 2009 revealed there were two large submarine slides on Hawkesbury Island during the mid-Holocene sometime between 5,000 and 10,000 years ago 

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.

Table of Seismic monitoring and GPS stations in northern BC from the Geological Survey of Canada (Geological Survey of Canada)
Table of Seismic monitoring and GPS stations in northern BC from the Geological Survey of Canada (Geological Survey of Canada)

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.

Related Commentary: The earthshaking difference between Enbridge and LNG

Download the Geological Survey Studies (PDF)

Baseline Assessment of Seismic Hazards in British Columbia’s North Coast 2016

North Coast Geohazards 2016 Seismology Update

Modified Mercalli Intensity Scale

(from US Geological Survey )

Intensity Shaking Description/Damage
I Not felt Not felt except by a very few under especially favorable conditions.
II Weak Felt only by a few persons at rest,especially on upper floors of buildings.
III Weak 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.
IV Light 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.
V Moderate Felt by nearly everyone; many awakened. Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.
VI Strong Felt by all, many frightened. Some heavy furniture moved; a few instances of fallen plaster. Damage slight.
VII Very strong 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.
VIII Severe 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.
IX Violent 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.
X Extreme Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations. Rails bent.

“Devastating megathrust earthquake” a “substantial hazard” for Haida Gwaii, Canada-US study warns

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.

New Douglas Channel geological studies near completion

Is Kitimat ready for a “big one?”

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.

A diagram of the situation  off Haida Gwaii that triggered the October 2012 "mini megathrust" earthquake seen at the lower centre, while the 1949 slip strike   earthquake is seen at the top. (Bulletin of the Seismological Society of America)
A diagram of the situation off Haida Gwaii that triggered the October 2012 “mini megathrust” earthquake seen at the lower centre, while the 1949 slip strike earthquake is seen at the top. (Bulletin of the Seismological Society of America)

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.

Map showing the pattern of earthquakes along the Queen Charlotte Fairweather Fault system and the location of the Queen Charlotte Terrace.  (Bulletin of the Seismological Society of America)
Map showing the pattern of earthquakes along the Queen Charlotte Fairweather Fault system and the location of the Queen Charlotte Terrace. (Bulletin of the Seismological Society of America)

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.

Aftershocks
.

Map showing the pattern of aftershocks following the October 2012 Haida Gwaii earthquake. (Bulletin of the Seismological Society of America)
Map showing the pattern of aftershocks following the October 2012 Haida Gwaii earthquake. (Bulletin of the Seismological Society of America)

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

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.

Transform fault
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.

Historic earthquakes.
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.


Related links
Kitimat to issue tsunami hazard and evacuation map

Afterearthquake Kitimat must immediately upgrade emergency communications

The earthshaking difference between Enbridge and LNG

DFO study on ancient Douglas Chanel tsunamis show minimal impact on Kitimat, devastation at Hartley Bay

Geological Survey of Canada identifies tsunami hazard, possible fault line on Douglas Channel

Scientists identify major Japanses style tsunami hazard for west coast

New Douglas Channel geological studies near completion

Three studies of the geology of Douglas Channel are near completion and publication, according to Natural Resources Canada. That news comes as studies, released today, warn of a major megathrust earthquake on the fault west of Haida Gwaii.

Northwest Coast Energy News asked the Geological Survey of Canada if there were any recent updates available after the agency said that a survey had located a “possible fault” on Hawkesbury Island during studies for the Enbridge Northern Gateway Joint Review Panel.

“Devastating megathrust earthquake” a “substantial hazard” for Haida Gwaii, Canada-US study warns

Is Kitimat ready for a “big one?”

Natural Resources Canada responded with a statement: “NRCan continues to conduct research studies in the area, including study of possible faults. Three scientific expeditions have been completed on board Coast Guard research ships. The first two reports are in the final stages of editing, and will be published in the coming months. The third expedition was just completed; therefore the third report will be available later.”

The initial joint survey by the Geological Survey of Canada and Fisheries and Oceans in September 2012, found a tsunami hazard and a possible seismic fault in Douglas Channel near Kitimat.

Fault zone map Douglas Chanel
A 2012 map from the Geological Survey of Canada showing the line of a possible seismic fault on Douglas Channel (Geological Survey of Canada)

The follow up study by Fisheries and Oceans, released about three weeks after the Haida Gwaii earthquake, in November 2012,  identified two slope failure events on the southern end of Hawkesbury Island during the mid-Holecene period, between 5,000 and 10,000 years ago. That study showed that the tsunami from the slope failure reaching Kitimat would have been about 60 centimetres or 23 inches. Hartley Bay would have been hit by a wave height of 7.5 metres or about 25 feet.

More recently there were slope failures nearer to Kitimat. The first slope failure occurred on October 17, 1974, triggering a 2.4 metre tsunami at low tide. Then on April 27, 1975 there was a second slope failure near low tide on the northeast slope of the Kitimat Arm that generated an 8.2 metre tsunami. The 1975 tsunami destroyed the Northland Navigation dock near Kitimat and damaged the Haisla First Nation docks at Kitamaat Village.

Thomas James, of the Geological Survey told Northwest Coast Energy news about the team’s finding on the Haida Gwaii earthquake: “The studies focused on the Haida Gwaii and Craig earthquakes which happened at the Pacific and North American plate boundary, west of Haida Gwaii, so east of Haida Gwaii there’s no comparable plate boundaries that gives rise of historic sieismisticity.”

As well as the fact that recent studies say the mainland margin coastal zone has had very little historical seismicity, it adds no currently active faults have been identified. A study ten years ago identified some very ancient faults which have not been active since the Eocene, about 33 to 56 million years ago.
GPS studies show that in northwestern British Columbia coastal block is moving northeast at the rate of just 5 millimetres a year.

Related links
Kitimat to issue tsunami hazard and evacuation map

Afterearthquake Kitimat must immediately upgrade emergency communications

The earthshaking difference between Enbridge and LNG

DFO study on ancient Douglas Chanel tsunamis show minimal impact on Kitimat, devastation at Hartley Bay

Geological Survey of Canada identifies tsunami hazard, possible fault line on Douglas Channel

Scientists identify major Japanses style tsunami hazard for west coast

Is Kitimat ready for a “big one?”

Kitimat Emergency Coordinator Bob McLeod
Kitimat Emergency Coordinator Bob McLeod at the earthquake postmortem Oct. 29, 2012 (Robin Rowland/Northwest Coast Energy News)

Studies of the October 2012 magnitude 7.8 Haida Gwaii earthquake show that the region is vulnerable to a “major megathrust” earthquake along a newly confirmed fault line west of the islands.

That earthquake was felt in Kitimat and Kitamaat Village and a tsunami warning was issued within a few minutes.

So have the District of Kitimat, the Haisla Nation Council or Rio Tinto Alcan changed or upgrading their earthquake and tsunami plans in the past couple of years?

“Devastating megathrust earthquake” a “substantial hazard” for Haida Gwaii, Canada-US study warns

New Douglas Channel geological studies near completion

Bob McLeod, who recently retired as the District of Kitimat’s emergency coordinator, told Northwest Coast Energy News: “I think we’ve done quite a bit. One of the biggest issues in the first one was trying to get information out. We’ve come a long way on that. Whether you reach everyone or not, that’s another thing, because you never reach everybody. One of the critical things to me is getting the information out so you avoid all this Facebook, Twitter speculating and rumour. The communications aspect has improved a hundred fold.

“We did more work on the mapping and planning. Over the course of the last year, there were a lot of meetings with industry and various stakeholders, discussing emergency preparedness in general but touching on some of these other things as well.

“One of the things we did was to try to set up some shelter points. We have an agreement with the Baptist Church, the Catholic Church and the Seventh Day Adventists. They’re strategically located and could be gathering points for the various neighborhoods if necessary.

“We’ve also done quite a lot of work on Riverlodge as a group lodging centre, thinking in terms of an earthquake where there may be damage and you have to move people.

“We did look at the evacuation planning and we’ve had a couple of exercises involving that, looking strategically about how can you move people from certain neighborhoods, asking which neighborhoods would be at the most risk if you ended up with a tsunami situation.

As for tsunamis, McLeod said, “From everything we’ve heard and been told, tsunamis in extremely deep water like that is not going to be as dangerous as one in shallower water, but the possibility is still there.

“The thrusts are the killers when it comes to tsunamis, but there is a very good warning system on the tsunamis. We do get very very rapid feedback on the earthquakes.

“The only danger in that regard is if you have a severe earthquake and you have part of a mountain drop into the salt chuck, you’re going to get a massive wave and you’re going to get no warning whatsoever, like the Moon Bay collapse in the seventies.

“The emergency plan is in good shape. We scheduled a number of exercises last year through training programs.

“One of the things I personally push is personal preparedness. I think as a community, we fail greatly at that. That was evident even during the snowstorm. People are not just prepared to look after themselves, it’s unfortunate. You just have to keep chipping away.”

Last week, Northwest Coast Energy News asked Rio Tinto Alcan and the Haisla Nation Council if either could comment on updated earthquake or tsunami response plans. So we have received no answers.

 

Related links
Kitimat to issue tsunami hazard and evacuation map

After earthquake Kitimat must immediately upgrade emergency communications

The earthshaking difference between Enbridge and LNG

DFO study on ancient Douglas Chanel tsunamis show minimal impact on Kitimat, devastation at Hartley Bay

Geological Survey of Canada identifies tsunami hazard, possible fault line on Douglas Channel

Scientists identify major Japanses style tsunami hazard for west coast

 

Commentary: The earthshaking difference between Enbridge and LNG

Joint Review Panel
The Northern Gateway Joint Review panel, Kenneth Bateman, Sheila Leggett and Hans Matthews, listen to final arguments in Terrace, June 17, 2013. (Robin Rowland/Northwest Coast Energy News)

Buried deep in the LNG Canada environmental assessment application, a reader will find a key difference in attitude with at least one of the group of companies planning liquified natural gas development in the northwest and Enbridge Northern Gateway.

It’s an earthshaking difference, since it’s all about earthquakes.

The documents filed by LNG Canada with the BC Environmental Assessment Office and the Canadian Environmental Assessment Agency acknowledge that there is a possibility of an earthquake (a one in 2,475 year event) at the LNG terminal site.

Northwestern British Columbia was shaken by two major earthquakes in the months before the Joint Review Panel concluded its hearings in Terrace. Both were far from Kitimat, but felt across the District. On October 27, 2012, there was a magnitude 7.8 earthquake on the Queen Charlotte Fault off Haida Gwaii. That quake triggered a tsunami warning, although the actual tsunami was generally limited to the coast of Haida Gwaii. Both landline and mobile phone service in Kitimat was briefly disrupted by both the quake and overloads on the system. Kitimat was also shaken by the 7.5 magnitude earthquake centered at Craig, Alaska a few weeks later on January 9, 2013.

With the exception of one vague reference in its final argument documents presented to the Joint Review Panel, Enbridge has stubbornly refused to consider any seismic risk to the region.

That was the company’s policy long before the October. 27, 2012 Haida Gwaii earthquake and was Enbridge policy after October 27, 2012.

In a public meeting in Kitimat on September 20, 2011, more than a year before the Haida Gwaii earthquake, John Carruthers, Northern Gateway president, insisted to skeptical questioners at a community forum at Mount Elizabeth Theatre that there was no earthquake danger to the proposed Northern Gateway pipeline and bitumen terminal in Kitimat.  One of the questioners, Danny Nunes, of Kitimat, asked could the pipes withstand an earthquake? Carruthers repeated that Kitimat was not in an earthquake zone, that the fault was off Haida Gwaii and so would not affect Kitimat.

After the September, 2011 meeting, I asked Carruthers if Enbridge knew about the March 27,1964 “Good Friday” magnitude 9.2 Alaska earthquake that, because of its high magnitude, had caused major shaking in Kitimat. That earthquake destroyed much of Anchorage and triggered tsunamis that caused damage and death across Alaska and in parts of British Columbia, Oregon and California.

Carruthers promised to get back to me and never did.

On June 17, 2013, six months after the Craig, Alaska earthquake, in his opening summation before the Joint Review Panel, Richard Neufeld, lead lawyer for Northern Gateway, stayed on message track, telling the JRP, referring to pipelines: “The route is not seismically unstable. The seismic risk along the pipeline right-of-way is low, with only a few locations of moderate risk encountered, none of which are within the Haisla territory.”

That brought a gasp from spectators in the room, or at least those who had felt the October and January earthquakes.

The following day, June 18, Murray Minchin of Douglas Channel Watch found an anomaly in the Enbridge documentation, arguing in the group’s summation:

“The Proponent’s written final argument gets on shaky ground regarding design and construction of the storage tanks on a ridge beside Douglas Channel in paragraph 249 where they say:

“‘It also involves the safe construction and operation of the Kitimat terminal in Kitimat Arm in an area subject to seismic activity which encompasses both terrestrial and marine components.’

“Now, that’s interesting because isn’t that the first time — the first admission by the Proponent in a little over 10,000 pages of documents that the area they intend to build their project is in a seismically-active area?

“Haven’t they been telling us all along to this point that the only seismic concerns would be from the distant Queen Charlotte fault off of Haida Gwaii?

“Now, this completely contradicts Mr. Neufeld’s statement yesterday where he described the Project area as not “seismically unstable”. So what is it? This is their final argument and they’re contradicting themselves.”

Minchin went on to quote from the Enbridge argument: “’Seismic conditions in the project area have also been addressed.’

“Well, really? Is that a truthful statement, considering Natural Resources Canada has only submitted a preliminary report concerning a 50-kilometre fault line and massive submarine landslides they accidentally discovered last year in Douglas Channel while doing a modern survey of the Channel for navigation hazards.

“How can the Proponent claim to have adequately addressed seismic forces in their design of this Project when they don’t know what those forces are or for what duration they may be subjected to those forces.

“Has there ever been a paleoseismological study in the Project area to establish past earthquake or tsunami history?

“Wouldn’t it be in the best interest of the Proponent, the Panel and Canadians to know the risks before 1.3 billion litres of liquid petroleum products are allowed to be stored on a low ridge right beside Douglas Channel?”

In his final rebuttal on June 24, Neufeld did not address the contradictions that Minchin had pointed out.

Compare Enbridge’s attitude to the view of LNG Canada, which at very least, appears willing to consider that major events could have adverse consequences on the terminal and liquifaction facilities.

    • The first one is a bit puzzling to Kitimat residents “A 1 in 100 year 24 hour rain event,” after all the town often gets rain for 24 hours straight or more fairly often.
    • The second, 1 in 200 year flood of the Kitimat River. Flooding has always been a concern and will be even more so, because as the pipelines come into town, whether natural gas or bitumen, those pipelines will be close to the river bank.
    • The 1 in 2,475 year seismic event. That figure is probably correct for a local event given the geology of the Kitimat Valley—unless, of course, the fault line discovered by the Geological Survey of Canada on Hawksbury Island proves to be a potential danger.
    • A tsunami.
    • Change in flow of the Kitimat River.
    • Even more interesting is that LNG Canada is willing to consider possible effects of climate change on the project, saying: “Predicted climate change effects during the project lifecycle on sea-level rise, precipitation and temperature. Where relevant and possible, the implications of such climate induced changes to the extreme weather events given above will also be addressed.”

.

Although the hydrocarbon industry as a whole is reluctant to acknowledge climate change, it appears that on a practical level, the LNG Canada partners, if they are about to invest billions of dollars in a natural gas liquifaction plant and marine terminal, will certainly take steps to protect that specific investment from the effects of climate change.

On the other hand, the National Energy Board, as matter of policy and the Northern Gateway Joint Review Panel, both still stubbornly refuse to even consider any effects of climate change, even possible effects locally on a specific project application.

The Joint Review Panel decision on the Northern Gateway is expected sometime in the next three weeks. While most reports seem to indicate that the decision will be released after Christmas before the Dec. 30 deadline, there has been recent media speculation that the decision could be released next week.

In the meantime, Enbridge has pulled out all stops in a public relations campaign to build support for the Northern Gateway. While a recent poll indicates that advertising campaign may be having some success in the Lower Mainland, the same poll showed that 65 per cent of northern BC residents oppose or strongly oppose the Northern Gateway.

The problem for Enbridge is that the new public relations campaign is repeating the blunders that began when they first proposed Northern Gateway in 2005. There have been meetings across the northwest, but those meetings have been invitation only affairs at chambers of commerce and community advisory boards, with possible opponents or skeptics and media perceived as critical of Enbridge not invited. So Enbridge still wants to control the message and will only talk to friendly gatherings.

Then there are the television spots featuring Janet Holder, the Enbridge vice president in charge of Northern Gateway, supposedly showing her commitment to wilderness. Those commercials would have had more credibility if the agency had produced the ads with actual video of Holder walking through the bush, rather than shooting the spots in front of a green screen in a studio, with pristine wilderness stock video in the background, and Holder acting as if she was a model for an adventure clothing company rather than  vice president of a pipeline company.

Right-wing business columnists in Toronto and the countless Albertans fume at the so-called “hypocrisy” of British Columbians who support LNG and oppose bitumen.

Of course, those critics didn’t feel the earth move under their feet.  The critics don’t see the difference between natural gas and bitumen, differences very clear to the people of British Columbia.

It’s more than the fact, that so far, the LNG projects have been relatively open and willing to talk to potential adversaries,  as Chevron has done on the controversial Clio Bay project; more than the fact that if even a fraction of the LNG projects go ahead, the money coming into northwestern BC means that the handful of permanent jobs promised by Enbridge will be literally a drop in a bucket of warm bitumen.

Although there are many other environmental issues on the Northern Gateway project, the fact the potential for earthquakes in Kitimat is brushed off by Enbridge while LNG Canada is at least willing to consider the problem, sums it all up.

 

Updated with link to Sept. 2011  questions and answers

 

 

 

 

 

 

 

Japan Petroleum approves LNG import facility in Fukushima Prefecture

Media reports say that Japan Petroleum Exploration (Japex) has given final investment approval to build a liquified natural gas receiving terminal and storage facility  at the Soma Port in Shinchi, Fukushima Prefecture to receive Canadian LNG, probably from Prince Rupert.

The company will also build a 40 kilometre connecting pipeline to move the natural gas to Japex’s main pipeline which will then connect with natural gas storage facilities in  Natori in Miyagi Prefecture and another facility in Niigata Prefecture on the Sea of Japan.

The Soma port was severely damaged in the March, 2011, earthquake and tsunami.

“We want to help areas affected by the disaster to create employment and secure a stable supply of energy,” Shoichi Ishii, Japex senior managing director,  was quoted by the Japanese newspaper Ashai Shimbum at a news conference on Nov. 27.

Japex owns 10 per cent of the planned Petronas LNG export terminal at Prince Rupert, which is expected to have an annual capacity of 12 million metric tons.

Japex plans to import 1.2 million tonnes of LNG made from  Canadian shale gas a year starting in 2018. The construction of the new LNG terminal in Shinchi, is scheduled for completion in 2017 and will start in 2014, at a cost of $587 million US.

The reports say with LNG import facilities on both the east and west coasts, that means Japan is ensuring a stable supply of LNG. If an earthquake or tsunami hits one coast, the other would likely be spared.

Ashai Shimbum also reports that Japex is considering building at an LNG fired power plant near the planned import and storage facilities to sell power to the struggling and controversial Tokyo Electric Power Co, owner of the nuclear power plant in Fukushima Prefecture that was destroyed in the March, 2011, earthquake and tsunami.

The newspaper says that because Japex does not have experience operating a thermal plant, it intends to work with other companies to run the new powerhouse.

Related The Australian Fukushima fallout fuels LNG demand

 

 

Harper government stalling on earthquake readiness for Haida Gwaii, Cullen says

The Harper government is stalling on requests for better earthquake preparation on Haida Gwaii, according to the NDP MP for Skeena Bulkley Valley, Nathan Cullen.

Speaking to northwest reporters on Thursday, February 28, Cullen who is NDP House Leader, said: “The government has been stalling since November when we’ve been asking them to meet the communities and meet their demands for funding, because as we see more earthquakes come, the support hasn’t been there from the federal government.”

The Skeena Bulkley Valley riding includes Haida Gwaii which was hit by a major 7.7 magnitude earthquake on October 27, 2012. Haida Gwaii and the northwest coast was shaken with numerous aftershocks through the rest of October and November. The most recent were 4.3 magnitude aftershock on February 24 and 4.5 magnitude aftershock on February 25. 

On January 5, 2013, another 7.5 magnitude earthquake struck near Craig, Alaska. That quake was also felt throughout northwestern BC.

Both big quakes prompted tsunami warnings.

“The communities have done their work,” Cullen said. “We’ve given the government three months now. Earthquakes continue to still happen,

“Rather than shedding tears if something goes wrong, the government should fix the problems. We know exactly where the funding can be coordinated and effective particularly in Haida Gwaii, there’s been a lot of work done on behalf of their communities especially by their municipal leaders.

“The federal government simply has to say yes, to meet with them, to find some of those funding solutions. This is not rocket science.

“Maybe because there aren’t earthquakes in Ottawa, the Harper government doesn’t seem to think these things are a concern to people. But they are. And let’s not wait until a tragedy happens before we start to make some moves.”

Cullen noted that the federal government had recently budgeted $680,000 for new LED lights for the communities on Haida Gwaii.

“I am not going to speak against the need to put LED lights in but’s obvious that the federal government’s priorities are not aligned with what’s actually needed on the ground. People have been calling for this for years. We’ve seen tsunami warnings before. And there’s some good and reasonable fixes.

“The role of the federal government emergency preparedness requires this,” Cullen said, but then he added that, “Now one thing to keep in mind is that this federal conservative government wants to get out of anything to do with emergency readiness and response,” pointing to cutbacks in the budget for First Nations police forces.

Unmentioned at the news conference was that likely also includes the Coast Guard cutbacks on the west including, including the highly unpopular and controversial closing of the Kitsalano Coast Guard base in Vancouver

Cullen said he was hoping to meet with the cabinet ministers responsible to get more action on earthquake readiness on Haida Gwaii.

Related:

After the earthquake: Kitimat must immediately upgrade its emergency communications
Oct. 28, 2012

The tsunami, Twitter and the Zones: Did social media amplify government generated confusion?
Nov. 4. 2012

DFO study on ancient Douglas Channel tsunamis shows minimal impact on Kitimat, devastation at Hartley Bay
Nov. 17, 2012

 

DFO study on ancient Douglas Channel tsunamis shows minimal impact on Kitimat, devastation at Hartley Bay

A follow up study by the Department of Fisheries and Oceans on the discovery of prehistoric slope failure tsunamis in Douglas Channel concludes that the events would have had minimal impact on Kitimat but would have destroyed Hartley Bay.

The studies were filed by DFO with the Northern Gateway Joint Review Panel on Friday, November 16, following an earlier study the Geological Survey of Canada that reported the discovery of the submarine slope failures. The filing comes just three weeks after the region was shaken by a 7.7 magnitude earthquake off Haida Gwaii and a subsequent coast-wide tsunami warning.

The DFO follow up study was aimed at better understanding the dynamics of tsunamis during the two slope failure events on the southern end of Hawkesbury Island during the mid-Holecene period, between 5,000 and10,000 years ago.

The wave dynamic model study does not address the discovery by the Geological Survey of Canada of a possible fault line along Hawkesbury Island which could have been the cause of the slope failures.

The study estimates that the wave amplitude of the first tsunami reaching the proposed Enbridge Northern Gateway terminal site near Kitimat would have been about .09 to .12 metres. Since the actual wave height hitting land from a tsunami is one half of the amplitude, the height of tsunami waves reaching Kitimat at the time would have been about 60 centimetres or 23 inches. At Hartley Bay, on the other hand, the maximum estimated wave amplitude from the second tsunami would have been 15 metres, meaning a wave height of 7.5 metres or about 25 feet.

The main reason for the difference is that both the submarine slope failures occurred south of  the dogleg in Douglas Channel at Gertrude Point. That meant the configuration of the channel from Gertrude Point up to Kitimat would lessen the amplitude whereas because Hartley Bay was so close, it would be hit by a higher amplitude. The report says that because of their relatively short wavelengths, the tsunami waves undergo multiple reflections that the “high degree of scattering from the complex shoreline and bottom topography in Douglas Channel” would “combined with the flux of tsunami energy through adjoining waterways and channels” have caused a rapid decrease in the energy of the waves with distance south and north of the slide area.

The study also points out a crucial difference between the ancient slides and the two that occurred near Kitimat in 1974 and 1975, while the land near the head of the Kitimat arm were largely composed of material laid down by the glaciers, the large slope failures on Hawkesbury Island were blocks of an extremely hard igneous rock called diorite. Each of the prehistoric slides would have consisted of about 65 million cubic metres of rock.

The DFO report says

Coastal British Columbia is an area of steep slopes, extreme seasonal variations in soil moisture, large tidal ranges, and the highest seismicity in Canada. Hazards of this form have been well documented for the coastal region of British Columbia, and other fjord regions of the world’s oceans, including Alaska and Norway. These factors increase the potential for both submarine and subaerial slope failures in the region. Such events generally take place in relatively shallow and confined inner coastal waterways, and can present hazards in terms of tsunami wave generation.

The two prehistoric submarine slides are located about 10 kilometres apart on the
slope of southern Douglas Channel, near the southern end of Hawkesbury Island

The report says:

The failures are defined by scallop-shaped hollows located along the edge of the fiord wall and appear to be associated with detached blocks that extend out several hundred metres into the channel. The two block slides identified in Douglas Channel are characteristic of rigid-body submarine landslides, which differ considerably from the well-documented viscous submarine landslides with a lower specific gravity (density relative to water) of about 1.5 that occurred to the north of Douglas Channel along the inner slope of Kitimat Arm in 1974 and 1975.

The report’s modelling is “considered minimum values” because the do not include debris that would have spread into the fiord after initial slide. That debris is now buried by a thick layer of post-slide sediment.

DFO diagram of the model of Slide A on Hawkesbury Island (DFO)

The reconstruction model shows that the head of the more northern slide began at a depth of around 60 to 100 metre, while that of the more southern slide began at a depth of 75 to 120 metres.

The slides would have moved down slope at about 25 metres per second, coming to rest after about 30 seconds, 250 to 350 metres from the slope at a depth of 400 metres.

The northern slide, called by the scientists Slide A:

would have generated extremely large waves in the immediate vicinity of the failure
region within a minute of the submarine landslide. Waves in the numerical simulations reach amplitudes of 30 to 40 metres at the coast near the slide area

Submarine landslides cause delays between the arrival of the first waves and the arrival of subsequent higher waves, increasing in distance from the slide, because of “reflections and non-linear interaction” along the shoreline. For Slide A, the maximum wave amplitudes at Hartley Bay would have been six metres (meaning three metre waves) “Large amplitude waves with typical periods of around 50 seconds would continue for several tens of minutes.”

The leading tsunami waves generated by Slide A reach Kitimat Arm in roughly 20 min and have small amplitudes of only a few centimetres. Although later waves have higher amplitudes, the maximum wave amplitudes (which occur 50-55 minnutes after the failure event) are still only around 0.09 to 0.12 metres.

The southern slide on Hawkesbury, called Slide B by the scientists, would have moved 400 metres before stopping. It stared at a greater depth than Slide A, with not as much vertical displacement than Slide A. That means Slide B was slower than Slide A.

Slide B:

would have generated large waves in the vicinity of the failure region. Simulated waves reach the coast adjacent to the slide region within a minute of the failure event, with wave amplitudes of up to 10 metres. The waves also hit the opposite site of the channel within a minute of the failure event and then take an additional minute to reach Hartley Bay where waves reach amplitudes of 15 metres/ Powerful oscillations in the bay last for tens of minutes.
Waves with high amplitudes (more than 2 metres) also occur in the southern part of Douglas Channel, and in certain locations of Verney Passage.

According to the models, the leading tsunami waves would have reached the Kitimat Arm 22 minutes after the start of the slide. The maximum waves would have had amplitudes of 0.08 metres to 0.3 metres (6 inches), reach the Kitimat Arm 45 to 60 minutes after the start of the failure event.

The the tsunami waves generated by Slide B that impact Kitimat Arm,  although still of low amplitude, were somewhat higher than those generated by Slide A, despite the fact that Slide B was located further to the south and generated less energetic waves in the source region than Slide A.

This seeming paradox is explained by the slower motion of Slide B, which causes it to generate more wave energy in the low frequency band…Due to their reduced scattering and reflection, the relatively long and lower frequency waves generated by Slide B propagate more readily through the complex fjord system than the relatively short and higher frequency waves generated by Slide A.

Specifically addressing the proposed site of the Enbridge bitumen terminal, as well as potential tanker traffic in Douglas Channel, the detailed explanation of the modelling accompanying the DFO report says:

If similar submarine slides were to occur again somewhere in the same general area, they could present a significant risk to navigation and to nearby shore installations and coastal communities….

As with the tsunami generation regions, the highest waves and strongest currents in any particular region of the coastal waterway would occur near the shoreline. Based on the numerical findings, tsunamis generated by submarine landslides of the form identified for the southern end of Douglas Channel would have heights and currents that could have major impacts on the coastline and vessel traffic at the time of the event throughout much of Douglas Channel, but a minor impact on water levels, currents and hence vessel traffic in Kitimat Arm. Hartley Bay, at the southern end of Douglas Channel, would be impacted by high waves and strong currents, whereas Kitimat, at the northern end of Kitimat Arm, would experience negligible wave effects. Additional modelling would be required to assess the characteristics of possible tsunamis originating beyond the area of the two identified slope failures.

At the estimated propagation speeds of about 65 metres per second, the detailed model says it takes roughly 10 to 15 minutes for the simulated waves to propagate approximately 40 to 45 kilometres to the intersection of Douglas Channel and Kitimat Arm, where peak wave amplitudes would be diminished to less than one metre. It takes another 15 minutes for the waves to reach sites near the proposed Enbridge facilities in Kitimat Arm where wave amplitudes would be reduced to a few tens of centimetres and associated currents to speeds less than a few tens of centimetres per second.

 

 

Slide tsunami area map
Slide tsunami area study map (DFO)

 

Fisheries and Oceans-Modelling Tsunamis Associated with Recently Identified Slope Failures in Douglas Channel  (pdf)

Numerical data for DFO tsunami study (link to JRP)

 

BC asks municipalities to “clarify” earthquake and tsunami response

Update:B.C. modifies, enhances emergency notification process (Official news release)

CBC: New tsunami warning protocol rolled out in B.C.

EmergencyInfoBC Please be advised that @EmergencyInfoBC is the only authorized emergency alert feed for Gov’t of BC.
Tweet Thu 8 Nov 11 48

The British Columbia Solicitor General’s department is asking northwest municipalities to “clarify the initial response actions” to the October 27 2012, magnitude 7.7 earthquake off Haida Gwaii and the resulting tsunami warning.

A covering letter to municipalities from Lori Wannamaker BC Deputy Solicitor General says the province is reviewing the response to the earthquake and tsunami and is “seeking input from affected community leaders.” The package includes a letter sent to Emergency Program Coordinators across British Columbia, adding: “Input will be sought in an endeavour to hear from those directly impacted as a measure of enhancing our operations and response,” adding. “Events like present all levels of government with a learning opportunity.”

In the main letter to the municipalities outlining emergency procedures, the department also offers a time line of its response to the incident.

Clarify the initial response actions

The package sent to municipalities by Rebecca Derlinger, Assistant Deputy Minister /Fire and Emergency Management Coordinator, opens by saying: “The earthquake/tsunami event on October 27, 2012 demonstrated the high level of emergency preparedness that has been undertaken by local governments in BC. Elected officials and emergency managers in all impacted communities deserve praise for a timely and effective response that was undertaken, including evacuations.”

But in the next paragraph the letter goes on to say: “Prior to the completion of the provincial debrief process, we would like to clarify the initial response actions of local government emergency management personnel including how information should be managed after an earthquake that impacts BC.”

The letter also says that “Local governments must complete a hazard risk and vulnerability analysis for their communities according to the Emergency Program Act and regulations, keeping in mind that all parts of British Columbia have a risk of earthquake impacts. Coastal communities have the added risk of tsunami.”

The letter then outlines three scenarios for various communities

  • Significant earthquake is felt in a community located in an area with tsunami risk
  • Earthquake is not felt, however, a community is located in an area with tsunami risk (teletsunami)
  • Earthquake is felt in a community that is not located in area that has tsunami risk

In all three scenarios it says Emergency Management BC “will provide the general public with ongoing situational awareness through:

  • EmergencyInfoBC blogsite
  • Social media such as Twitter
  • Mainstream media (press conferences and releases)

For areas such as Kitimat, which is in a possible tsunami zone, the letter advises “Local governments should undertake the following emergency response activities immediately following a significant earthquake (do not wait for official notification)

  • Activate their local emergency response plans and if deemed necessary
  • Active local first responders
  • Undertake public alerting and initiate evacuations of low lying areas
  • Open an emergency operations centre in a safe location
  • Report to EMBC
  • Ensure ongoing public messaging to their citizens
  • Gather information to develop situational awareness

For areas that don’t feel the earthquake, the province recommends

Local governments should undertake…emergency response activities immediately following the receipt of a West Coast Alaska Tsunami Warning Centre (or WCATTWC) and/or EMBC notification of a potential tsunami event. It then calls on local emergency officials to follow the same procedure outlined above “if a notification indicates an increased risk of a tsunami (warning or advisory only)

As you can see from the Twitter profile, Emergency Info BC works during normal office hours, Monday to Friday unless there is a declared emergency

The warnings October 27


In the letter the province outlines a time line of how the emergency system worked on October 27.

It says the provincial Tsunami Notification plan was activated at 8:10 pm. October 27, approximately four minutes after the earthquake.

In a provincial acronym soup it then says

The EMBC (Emergency Management BC) Emergency Coordination Centre initiated an internal resource request to activate the PECC (Provincial Emergency Coordination Centre) and the PREOCs (Provincial Regional Operations Centres).

EMBC and Temporary Emergency Assignment Management System (TEAMS) staff were in attendance at PECC and PREOCs by 8:33 pm.

“Based on the initial bulletin from WCATTWC, social media staff sent out a message via Twitter” at 8:48 pm At that time EMBC regional offices began contacting communities with potential tsunami risk by telephone. “Subject matter experts from Natural Resources Canada and Canadian Hydrographic Service were contacted by PECC at 8:30 pm and at 9 pm to review the information received from WCATWC.

“Based on these discussions, the PENS (Provincial Emergency Notification) was initiated at 9:05 while efforts to make contact with those communities under tsunami warning continued.

At 10:45 pm a media conference call was held by the Minister of Justice.

The letter continues to say that conference calls were held with EMBC, US state emergency management offices, and the West Coast Alaska Tsunami Warning Centre hourly until the final cancellation of the west coast warning by WCATWC at 2:47 am Sunday morning and by the province at 3:03 am

It concludes “Staff responsible for social media were actively engaged in informing the public.”

Denlinger’s letter then goes on to note that the provincial debrief will include “a discussion on the information flow from the province to emergency management stakeholders and the public (for example the use of social media as a communications tool for public awareness of the event)… This information….will assist in the creation of a provincial after action report and in the enhancement of subsequent provincial earthquake and tsunami response plans.”

How warnings worked on November 7

 

Earthquake November 7
Earthquake Nov. 7, 2012 (USGS)

On November 7, 2012, the US Geological Survey reported a 6.3 magnitude earthquake took place at 6:01 pm. Pacific Standard Time off the west coast of Vancouver Island, 186km (116mi) south southwest of Port Hardy.

At 6:06 I received an automatic text message from the West Coast Alaska Tsunami Warning Centre
Tsunami Info Stmt: M6.3 085Mi SW Port Alice, British Columbia 1802PST Nov 7: Tsunami NOT expected #WCATWC

At 6:07 I received an automatic tweet from Canadaquakes : @CANADAquakes: Automatic detection of seismic event: magnitude 4.4 – 7 Nov 18:01 PST – PORT HARDY, BC region

At 6:15, I received the WCATWC message on Twitter that I had received 9 minutes earlier via text
Tsunami Info Stmt: M6.3 085Mi SW Port Alice, British Columbia 1802PST Nov 7: Tsunami NOT expected #WCATWC

@EmergencyInfoBC retweets the WCATWC message

At 6:27 Canada quakes updated their tweet with corrected information: @CANADAquakes: EARTHQUAKE Mag=6.3 on 07 Nov at 18:01 PST. Details : http://t.co/OL9RTPKC 101 km SSW of Port Alice, BC

@EmergencyInfoBC retweets the CANADAquakes message

Analysis The province didn’t get it

Tweets from Emergency Info BCRead between the lines of the Solicitor General’s letter and a couple of things stand out. While at first the officials say things went fine according to procedures in the book, events appear to show that in practice, the system didn’t work as well as expected on the night of October 27.

First the province, reminds municipalities of that they “must complete a hazard risk and vulnerability analysis for the communities.”

Second, while EM BC social media staff were, according to the letter, “were actively engaged in informing the public,” there was actually scant evidence of that during the crucial first 90 minutes after the earthquake on Haida Gwaii. While the emergency coordination officials and bureaucrats apparently were well informed about what was happening, the public was not. As I pointed out in an earlier post, differences between the US and Canadian warning systems contributed to the confusion. As well there was a problem on both Twitter and Facebook of rumour, misleading and false information being posted on social media during that crucial 90 minutes.

The line about the “the use of social media as a communications tool for public awareness of the event” is a clear indication that not all went well with the EM BC Twitter feed the night of the Haida Gwaii earthquake.

While Emergency Info BC is a sort of blog, again you have to know to go there and it is only active during an emergency. There were no posting on the night of the earthquake and tsunami. The last “blog” was during the Johnson’s Landing landslide evacuation in July 2012, and even that doesn’t give much information. Looks like Emergency Info doesn’t understand that a blog entry that says “no danger, nothing much is happening” is just as important as evacuation instructions.

The main website is Emergency Management BC,  with a link to the Info site—if there is an emergency—not exactly a prime example of web design for someone in a hurry, whether an official, the media or the public, since it was what the web calls “brochure ware.”

The first indication of whether or not there would be major danger to the BC coast on Oct. 27 was at Langara Island at 9:16 pm. Local officials in northwest BC were monitoring Langara and the relatively low surge indicated–at least at that time– that danger was not as great as feared. Yet it was only seven minutes earlier that EM BC activated the Provincial Notification Program at 9:05, and that was an hour after it was known that the earthquake was 7.7 in magnitude, which had the potential for catastrophic damage. The tweets that I saw about the small surge at Langara, came from Prince Rupert. It is in a situation like the Langara monitoring that the Emergency Info blog would have been relevant.

The need for constant official updates is clear. Earthquakes do not work 8:30 to 4:30, Monday to Friday. The province has to be able to activate emergency notification much faster. If a web journalist whether working for the mainstream media or a responsible individual on a small site can tweet or post in seconds, usually working from a home office or even a smart phone, emergency officials can do the same.

In these days, travel by government officials is often frowned upon. A couple of months from now, when New York and New Jersey have recovered from the Superstorm Sandy and this weeks Nor’easter, a visit from BC emergency officials is in order to see how it is done.

The tsunami, Twitter and the Zones: Did social media amplify government generated confusion?

Kitimat, BC and New York City had one thing in common this week, the misuse and use of social media, Twitter and Facebook, that spread both accurate warnings and dangerous misinformation about an impending disaster. In the case of New York and the surrounding area, it was Superstorm Sandy that caused widespread devastation. For Kitimat it was the tsunami warning after the 7.7 earthquake off Haida Gwaii and no damage but a lot of worry for residents.

New York has a population of millions, it is the media centre for the United States, and much of the U.S. Northeast coast is still recovering from the horrendous damage from Superstorm Sandy.
Kitimat has a population of about 8,000 and my home town is off the media radar except when the Enbridge Northern Gateway pipeline issue pops up on the national assignment desks. If the October 27, 2012 tsunami from the Haida Gwaii earthquake did come up Douglas Channel to Kitimat harbour, it was so minimal that any water rise was scarcely noticed.

In one way New York (the state and the city) plus New Jersey and other states were ahead of Kitimat. In the US, there were numerous official sources on Twitter and Facebook, as well as those ubiquitous live TV news conferences with New York Mayor Michael Bloomberg or various state governors.

On October 27, neither Kitimat nor the nearby town of Terrace had any official emergency outlets on social media. In Kitimat, that may change as early as this Monday when District Council considers what happened last Saturday night.

It has been documented that there was no official response from Emergency Management British Columbia (still largely known under its former name Provincial Emergency Program) until an hour after the first earthquake report from the US Geological Survey. Only sometime later did BC’s provincial emergency officials hold a short conference call with reporters. (At the time the BC Liberals were holding a policy convention at Whistler. After the conference call, TV reporters at the convention in Whistler were doing live reports with taped clips of Attorney General Shirley Bond. It should have been easy for Bond and other senior government officials, including Premier Christy Clark–who is plummeting the polls– to hold a live news conference just as US state governors and mayors did later in the week when it came to Superstorm Sandy)

So in that hour of silence from the BC government, one question that has to be raised is: Were the tsunami warnings so completely uncoordinated–at least as far as the public is concerned– that that was one cause of the misinformation and inaccurate information on Twitter and Facebook? Or did confusing information from authorities simply compound and amplify the social media misinformation that was already spreading across British Columbia and around the world?

Here in the northwest, the two area fire chiefs Trent Bossence of Kitimat and John Klie of Terrace have said after the quake that landline phones and some cell phones were out, in some areas up to an hour after the first shock. Klie told CFTK’s Tyler Noble on Open Connection that after the landline phones came back up the Terrace fire department was flooded with calls from people “who wanted it now.” The ability of firefighters to get information was then delayed “because so many people were trying to get through.”

Kitimat has the advantage of being a small town. Emergency services already had scheduled a volunteer recruiting session last Monday night (October 29) for Emergency Social Services–the folks who run, coordinate and work in reception centres during an emergency–so it was easy to turn that meeting into a earthquake/tsunami warning post mortem. (Imagine that happening in New York?)

The most important issue on Saturday night was the false information on both Facebook and Twitter that the Kildala neighbourhood was being evacuated due to the tsunami warning. Other false information on social media indicated that the giant Bechtel work camp at the Rio Tinto Alcan Kitimat Modernization Project was also being evacuated.

As Kitimat’s Emergency Plan Coordinator Bob McLeod told the earthquake post mortem about the information on Facebook and Twitter:

Kitimat Emergency Coordinator Bob McLeod
Kitimat Emergency Coordinator Bob McLeod at the earthquake postmortem Oct. 29, 2012 (Robin Rowland/Northwest Coast Energy News)

“Your aim is to be saving people, and you’re not saving people. There was one case where someone was going around banging on doors in Kildala, telling them to get out. I think it was over when he was in the lockup that night. But this is the type of foolishness that goes on. You have people going on Facebook saying ‘Alcan’s been evacuated. they’re evacuating Kildala.’ I am going to be generous and say it is misinformation… It was a blatant lie. And that does not help.”

 

 

(For those outside Kitimat you can check the town on Google maps) As seen on this screen grab, Kildala is a low lying part of town. The area north of  Highway 37 is higher on a hill. Closer to the ocean at Douglas Channel are the Bechtel/RTA Kitimat Modernization Project work camps.

Map of Kitimat

Walter McFarlane of the Kitimat Daily recounted his experiences at the post mortem. (We were both at a Haisla dinner at Kitamaat Village when the quake struck. See my earlier story here and McFarlane’s Kitimat Daily story here).

After driving from the village to the town, McFarlane told the meeting that he stopped at the town viewpoint where “people were telling me they had already been evacuated out of the Kildala neighbourhood, so my first stop after that was the fire department.” The fire hall is about a couple of blocks from the viewpoint, so it was easy to get accurate information from the fire department.

McFarlane continued, “I found the night of the earthquake that no information is just as bad as wrong information. People were calling me on my cell saying why does the Kitimat Daily say we have to evacuate.” That is because the Daily republished a warning from the Pacific Tsunami Warning Centre that “said tsunami warning, evacuation for the north coast. People were saying we’re on the north coast, we got to go.”

I was about fifteen to twenty minutes behind McFarlane in reaching town. (I did not leave Kitamaat Village until after we heard the first tsunami warning.)  As soon as I got to back in cell  range, my cell phone started to beep with saved messages from my TV and radio news clients calling for information. When I got to my home office, my landline was still dead and would be for about another twenty minutes. The only source of information at that point was Google News, Facebook and Twitter.

I saw the initial, and it turns out general, warning from the Pacific Tsunami Warning Center. Soon I was also getting what I hoped was more specific information  on my marine radio from the Canadian Coast Guard Prince Rupert communications station.

But that, too was somewhat confusing. That Coast Guard advisory mentioned various zones, for example, Zone A and Zone B, but there was little specific context and that point I had no idea what Zone A meant. Prince Rupert Coast Guard Radio then went on to say evacuate low lying coastal areas. (transcript below)

With that confusion, and mindful of “when in doubt, leave it out,” I did not mention the zone system in any information I posted on Facebook and Twitter that night. I only retweeted official information or tweets from reporters I knew and trusted (and I did not see any tweeted official information from the province with a link to the page that identifies the official tsunami zones)

From the interview on CFTK, it appears that both the Kitimat and Terrace fire departments were also getting inadequate information.

“We went to our normal place to look EM BC (Emergency Management BC) and there was nothing there,so we went to Plan B to get information and went on from there,” Bossence told Tyler Noble.

Klie said: “We struggle with that every disaster big or small. Social media, I think emergency organizations are trying to tap into more and more. Up north we may be a little behind the eight ball but sure enough Twitter and Facebook information is out there instantly. Looking at Facebook with my son, I saw that they were evacuating whole cities and I knew that was not true. Because of my experience I can filter some of the information, but there is so much information out there that it’s hard to filter what’s real and not real. It’s an area where emergency coordinators have to get into because its the fastest way of getting information out.”

“Once the phone system came back online at the Fire Hall we got a flood of phone calls,” Bossence told CFTK, “it was nonstop and it was people wanting to know. ‘What’s going on? What are we going to do? Are we leaving?’ and they’re giving us ‘This is what is what I’m reading, this is what I’m being texted, on Facebook they’re saying we’re supposed to evacuate’ adding to that we had an individual going around claiming he was a fire department, he was going door to door and telling people to evacuate. That was the added issue we had to deal with. It was definitely misinformation and a sense of urgency that was coming out through the social network (and eventually the media) was big problem for us.”

In Kitimat, I was told about the man going door to door with inaccurate information and as soon as I confirmed it with reliable official sources, I posted that on both Twitter and Facebook, emphasizing there was, at that time, no evacuation order.

But every situation is different. In contrast, in Superstorm Sandy, another story about men going door to door in Williamsburg, a section of Brooklyn  was not true, as can be seen in an article summing problems with Twitter in New York, where Jared Keller of Bloomberg reported

I experienced this firsthand during Hurricane Sandy. After retweeting a message warning about muggers in Williamsburg dressed as Con Ed workers as an experiment, I received two sceptical responses checking the claim within 15 minutes, both from people who work in the media industry and spend a significant amount of time on Twitter. Within an hour, I received a mass text message from friends of mine who aren’t completely plugged into the social Web with the same warning: “I just read a news alert of two separate reports of people posing as coned workers, knocking on people’s door and robbing them at gunpoint in Williamsburg. I just want to pass along the info. Stay safe and maybe don’t answer your door.” Two other friends responded with thanks.

Keller goes on to stay “I know a lot of people, especially on Facebook, who end up believing whatever they see first,” says Kate Gardiner, a social media journalist. “It’s almost impossible to track something back to its point of origin there.”

You can read Keller’s complete article How Truth and Lies Spread on Twitter  here.

See also How to Tweet Responsibly During a Breaking-News Event by Garance Franke-Ruta  a senior editor at The Atlantic

With the earthquake and tsunami warning Saturday night, Twitter misinformation spread internationally. The first hashtag I saw was #bcquake, but as the the tsunami warning gained traction (especially after the warning was extended from BC and Alaska to Washington, Oregon and California and then to Hawaii) the more common hashtag #tsunami became prominent. As people outside BC began tweeting, they began using #Canadaquake and soon #prayforcanada also began to trend. Completely inaccurate information spread on #prayforcanada (believed to have originated in Indonesia) that it was Vancouver, not the north coast that had been hit by the 7.7 magnitude earthquake.

Are you in the Zone?

At this point, one question has to be asked. The spread of information, first the well-intended but wrong, second just rumour and third, the deliberately misleading, has been seen in social media not only during the earthquake and tsunami on the West Coast last weekend, and during Superstorm Sandy on the East Coast but all the way back to the 2004 Christmas tsunami in Southeast Asia.

For the west coast in 2012, however, how much of the problem of misinformation on social media during the earthquake and tsunami warning was the fault of confusing information from the authorities? Just how were people going to interpret such general terms as “north coast” and “low lying areas.”?

From the BC Provincial Emergency Program you have to ask “What is Zone A?” It turns out by checking a day or so later that the province of British Columbia has created Tsunami Identification Zones.

Emergency Management Tsunami Zones
Before October 27, it is likely no one outside of the provincial bureaucracy had ever heard of the provincial tsunami zones. At that time no one in BC, either on Twitter or Facebook or through the media was identifying the BC Tsunami Zones for the public. Later on, the television networks put up maps showing Zones A and B —but that was only good if you had power and were watching the right channel. Kitimat Daily and Terrace Daily posted an official update at 10:42 long after the danger was past explaining the Zone system. It was no good at all if you were listening to news reports on radio or to Prince Rupert Coast Guard Radio on a fishing boat and had no access to the actual maps.

Compounding the confusion is that the US system appears to be very different from the Canadian.

Also the US system has two levels of warning. The Pacific Tsunami Warning Center sends out general warnings but hands over for a more specific warning map from the Alaska -based West Coast and Alaska Pacific Tsunami warning centre. It uses its own system of lettered and numbered zones for the west coast of North America. (See the Oct 27 tsunami advisory here  Note it is a Google maps plugin.)

 

Alaska BC tsunami warning map
Possibly adding to uncertainty for those who sail the coast of British Columbia, is that usually when the Canadian Coast Guard talks about zones on marine radio, it is talking about the fishing zones as defined by the Department of Fisheries and Oceans, which are numbered not lettered 

 

DFO Management areas
Fisheries management zones as defined by the Department of Fisheries and Oceams (DFO)

 

So in case of a tsunami warning, Kitimat is in Zone B for the province of British Columbia and the Provincial Emergency Program and in Zone BZ921 for the West Coast and Alaska Tsunami Warning Centre. For the much more familiar fisheries management areas Kitimat is in Zone 6 (which of course has nothing to do with a tsunami, it’s simply the coastal zone system everyone is familiar with)

Tsunami warning map
Adding to the confusion is the fact that the EM British Columbia map shows Terrace, far inland up the Skeena River is considered in Zone A, along with Prince Rupert for tsunami warnings (if a tsunami was big enough to reach Terrace along the Skeena River valley, then I can only assume that much of the west coast of North America would have already been wiped out).

Tsunami Zone A

 

The Monday Post mortem

Warning brochuresAt the Monday, October 29 post mortem, when McLeod outlined the events of October 27, he began by looking back three weeks, saying, “I have feeling of frustration about a couple of things. October 7, I took 4,000 brochures [How Prepared Are you if Disaster Strikes?] down to the post office to mail out to the residents of Kitimat, They were all delivered by the post office. On Sunday, I had people coming to me and saying what are we supposed to do in the case of an earthquake? It is really, really difficult to get people interested.”

McLeod said that after he felt the earthquake, he went online to check information and then went up to the fire hall, which is Kitimat’s emergency coordination centre. There he met Fire Chief Bossence, his deputy, the RCMP detachment commander Staff Sergeant Steve Corp and representatives from Bechtel and the Rio Tinto Alcan modernization project.

“For the first little while we were going on line trying to get information. The usual method of dissemination getting information it comes from the West coast and Alaska tsunami warning system, then it goes to Victoria, Victoria gives it to the geophysical specialists and they will confirm or deny what ever the information and then it goes to the Provincial Emergency Program and they shoot it out to coastal communities.

“While in this case you’re working with what you find out from different sources and you are trying to determine how reliable these sources are.”

“In our case, for me the first thing you do when you get word of an impending tidal wave [tsunami] action is check the tide. If you’re on a high tide, it’s a different situation than a low tide

“The movie version of a tidal wave is this 50 foot mountain of water roaring along and this is not what is going to happen particularly in Douglas Channel because of the depth. So you are going to see a surge such as we saw in Japan and it will be an increasing surge of water.

“We were told that potentially some sort of surge hitting Langara  [the northern most island in Haida Gwaii) at 9:16, 9:16 came and went and there was no notification of a noticeable surge of water. So were down to a non event and we were on a receding tide.” (See advisory below)

“Misinformation going out is not helpful,” McLeod said. “You’ve got to set up a stream of how you get information out to people and it’s a valid point. The District Website, the Facebook page, something like that can get information out. But again if you lose power where do get it? Text can work even locally with cell phones. if you’re in a dead area with a cell phone, you can still get text”

McLeod then asked the audience, mainly people ranging from their thirties to seventies if they text. Only four or five people put up their hands. “You people are going to be saved, the rest of us…” McLeod quipped.

If a conclusion can be drawn from the earthquake and tsunami warning in the Kitimat region on October 27, it’s not just that in an emergency inaccurate, incomplete or malicious information can spread a the speed of light on social media, it’s worse that incomplete, inadequate and confusing information from the authorities is amplified and distorted by rapid posting on social media. That concept is not new for anyone who has tried the phone chain game where the outcome is often completely different from the start.

If Gardiner is correct when she says “I know a lot of people, especially on Facebook, who end up believing whatever they see first,” the BC government delays made everything worse. People Tweeted the first thing they saw and the first thing people saw came from multiple and often conflicting sources.  Add that to those Tweets that were exaggeration, rumour and lies.

The problem in 2012 it is not one person talking to one person talking to one person, it is a Tweet or Facebook posting that go out to thousands, or millions of people and that’s a lot more dangerous.

McLeod said the post mortem who said emergency services is trying to get more information out to public, but he added. “The unfortunate part is that if you publish it this week, by Christmas no one will remember. If you start throwing it out every week, it becomes like a stop sign at the end of the street. Nobody sees it.”

(Coming next. If Kitimat had to evacuate)

Transcript of Prince Rupert Coast Guard Radio tsunami warning.

Pan pan. Pan pan. This is Prince Rupert Coast Guard Radio, Prince Rupert Coast Guard Radio. Warning for coastal British Columbia issued by Environment Canada on behalf of the British Columbia Provincial Emergency Program at 2057 Pacific Daylight Time Saturday 27 October. Tsunami warning for Zone A, the north coast and Haida Gwaii,Zone B, the central coast and including Bella Coola, Bella Bella and (unintelligible). A tsunami warning has been issued, if you are in a low-lying area coastal area, you are at risk and must move to higher ground or inland now.
Do not return until directed to do so. Closely monitor local radio stations for additional information from local authorities. Please minimize phone use in affected areas, for further information contact the provincial emergency program at website www. papa echo papa period bravo charlie period charlie alpha.Prince Rupert Coast Guard Radio over.

General warning from the Pacific Tsunami Warning Centre

000
WEPA42 PHEB 280341
TIBPAC

TSUNAMI BULLETIN NUMBER 003
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 0341Z 28 OCT 2012

THIS BULLETIN APPLIES TO AREAS WITHIN AND BORDERING THE PACIFIC
OCEAN AND ADJACENT SEAS…EXCEPT ALASKA…BRITISH COLUMBIA…
WASHINGTON…OREGON AND CALIFORNIA.

… TSUNAMI INFORMATION BULLETIN …

THIS BULLETIN IS FOR INFORMATION ONLY.

THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES. ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE
DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND
ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

ORIGIN TIME – 0304Z 28 OCT 2012
COORDINATES – 52.9 NORTH 131.9 WEST
DEPTH – 10 KM
LOCATION – QUEEN CHARLOTTE ISLANDS REGION
MAGNITUDE – 7.7

EVALUATION

NO DESTRUCTIVE WIDESPREAD TSUNAMI THREAT EXISTS BASED ON
HISTORICAL EARTHQUAKE AND TSUNAMI DATA.

HOWEVER – THE WEST COAST/ALASKA TSUNAMI WARNING CENTER HAS
ISSUED A REGIONAL WARNING FOR COASTS LOCATED NEAR THE EARTHQUAKE.
THIS CENTER WILL CONTINUE TO MONITOR THE SITUATION BUT DOES NOT
EXPECT A WIDER THREAT TO OCCUR.

THIS WILL BE THE ONLY BULLETIN ISSUED FOR THIS EVENT UNLESS
ADDITIONAL INFORMATION BECOMES AVAILABLE.

THE WEST COAST/ALASKA TSUNAMI WARNING CENTER WILL ISSUE PRODUCTS
FOR ALASKA…BRITISH COLUMBIA…WASHINGTON…OREGON…CALIFORNIA.

A more specific warning from the West Coast/Alaska Tsunami Warning Centre

 

WEAK51 PAAQ 280334
TSUAK1

BULLETIN
PUBLIC TSUNAMI MESSAGE NUMBER 2
NWS WEST COAST/ALASKA TSUNAMI WARNING CENTER PALMER AK
834 PM PDT SAT OCT 27 2012

THE MAGNITUDE IS UPDATED TO 7.7. THE WARNING ZONE REMAINS THE
SAME.

…THE TSUNAMI WARNING CONTINUES IN EFFECT FOR THE COASTAL
AREAS OF BRITISH COLUMBIA AND ALASKA FROM THE NORTH TIP OF
VANCOUVER ISLAND BRITISH COLUMBIA TO CAPE DECISION
ALASKA/LOCATED 85 MILES SE OF SITKA/…

…THIS MESSAGE IS INFORMATION ONLY FOR COASTAL AREAS OF
CALIFORNIA – OREGON – WASHINGTON AND BRITISH COLUMBIA FROM
THE CALIFORNIA-MEXICO BORDER TO THE NORTH TIP OF VANCOUVER
ISLAND BRITISH COLUMBIA…

…THIS MESSAGE IS INFORMATION ONLY FOR COASTAL AREAS OF
ALASKA FROM CAPE DECISION ALASKA/LOCATED 85 MILES SE OF
SITKA/ TO ATTU ALASKA…

A TSUNAMI WARNING MEANS… ALL COASTAL RESIDENTS IN THE WARNING
AREA WHO ARE NEAR THE BEACH OR IN LOW-LYING REGIONS SHOULD MOVE
IMMEDIATELY INLAND TO HIGHER GROUND AND AWAY FROM ALL HARBORS AND
INLETS INCLUDING THOSE SHELTERED DIRECTLY FROM THE SEA. THOSE
FEELING THE EARTH SHAKE… SEEING UNUSUAL WAVE ACTION… OR THE
WATER LEVEL RISING OR RECEDING MAY HAVE ONLY A FEW MINUTES BEFORE
THE TSUNAMI ARRIVAL AND SHOULD MOVE IMMEDIATELY. HOMES AND
SMALL BUILDINGS ARE NOT DESIGNED TO WITHSTAND TSUNAMI IMPACTS.
DO NOT STAY IN THESE STRUCTURES.

ALL RESIDENTS WITHIN THE WARNED AREA SHOULD BE ALERT FOR
INSTRUCTIONS BROADCAST FROM THEIR LOCAL CIVIL AUTHORITIES.
EARTHQUAKES OF THIS SIZE ARE KNOWN TO GENERATE TSUNAMIS.

AT 804 PM PACIFIC DAYLIGHT TIME ON OCTOBER 27 AN EARTHQUAKE WITH
PRELIMINARY MAGNITUDE 7.7 OCCURRED 25 MILES/40 KM SOUTH OF
SANDSPIT BRITISH COLUMBIA.
EARTHQUAKES OF THIS SIZE ARE KNOWN TO GENERATE TSUNAMIS.
IF A TSUNAMI HAS BEEN GENERATED THE WAVES WILL FIRST REACH
LANGARA ISLAND BRITISH COLUMBIA AT 916 PM PDT ON OCTOBER 27.
ESTIMATED TSUNAMI ARRIVAL TIMES AND MAPS ALONG WITH SAFETY RULES
AND OTHER INFORMATION CAN BE FOUND ON THE WEB SITE
WCATWC.ARH.NOAA.GOV.

TSUNAMIS CAN BE DANGEROUS WAVES THAT ARE NOT SURVIVABLE. WAVE
HEIGHTS ARE AMPLIFIED BY IRREGULAR SHORELINE AND ARE DIFFICULT TO
FORECAST. TSUNAMIS OFTEN APPEAR AS A STRONG SURGE AND MAY BE
PRECEDED BY A RECEDING WATER LEVEL. MARINERS IN WATER DEEPER
THAN 600 FEET SHOULD NOT BE AFFECTED BY A TSUNAMI. WAVE HEIGHTS
WILL INCREASE RAPIDLY AS WATER SHALLOWS. TSUNAMIS ARE A SERIES OF
OCEAN WAVES WHICH CAN BE DANGEROUS FOR SEVERAL HOURS AFTER THE
INITIAL WAVE ARRIVAL. DO NOT RETURN TO EVACUATED AREAS UNTIL AN
ALL CLEAR IS GIVEN BY LOCAL CIVIL AUTHORITIES.

PACIFIC COASTAL REGIONS OUTSIDE CALIFORNIA/ OREGON/ WASHINGTON/
BRITISH COLUMBIA AND ALASKA SHOULD REFER TO THE PACIFIC TSUNAMI
WARNING CENTER MESSAGES FOR INFORMATION ON THIS EVENT AT
PTWC.WEATHER.GOV.

THIS MESSAGE WILL BE UPDATED IN 30 MINUTES OR SOONER IF
THE SITUATION WARRANTS. THE TSUNAMI MESSAGE WILL REMAIN
IN EFFECT UNTIL FURTHER NOTICE. FOR FURTHER INFORMATION STAY TUNED
TO NOAA WEATHER RADIO… YOUR LOCAL TV OR RADIO STATIONS… OR SEE
THE WEB SITE WCATWC.ARH.NOAA.GOV.

$$

Did the media over react to the earthquake and tsunami warning?


There were also numerous Tweets on October 27, accusing the media of over reacting. The Haida Gwaii quake was 7.7 magnitude. Compare that to the Haiti earthquake on January 12, 2010 which was 7.0. The Christ Church, New Zealand earthquake on February 27, 2011 which caused major damage was 6.3 magnitude. So the Haida Gwaii earthquake was a major event. The tsunami warning that eventually reached as far off as Hawaii had to be taken seriously.

Fortunately Haida Gwaii is sparsely populated and there was minimal damage largely because most of the houses and buildings are wood and can absorb some of the shaking from an earthquake.

Given the tsunami damage in Southeast Asia in 2004 and in Japan in 2011, no media organization could ignore the developing story.

If there is justifiable criticism, it is that some media over hyped the story in the beginning, rather acting to reassure the public in a responsible manner. But the media that over hyped the earthquake and tsunami are the kind that would over hype any story. That is generally the result of management listening to “TV doctors” and media consultants who urge over hyping to increase ratings. (It often works). But those who,  quite early in the event, who tweeted that the media was overreacting, were themselves guilty of overreaction in their Tweets.