Latest news with #MichaelBostock
Yahoo
4 days ago
- Science
- Yahoo
Megathrust fault line off Haida Gwaii confirmed through new imaging
Scientists have confirmed that a fault line off the west coast of Haida Gwaii is of the megathrust variety, capable of generating large earthquakes and tsunamis. The conclusion was gleaned through hydrostatic imaging and measurements of the Queen Charlotte Fault where the Pacific tectonic plate meets the North American plate. The finding was published in Science Advances. The images show that instead of the plates sliding horizontally against each other, the Pacific plate is also colliding with and diving under the North American plate, in a process known as subduction. The friction created by subduction is what creates megathrust conditions, according to UBC professor and study co-author Michael Bostock. "For most of its length, the Queen Charlotte plate boundary is very much like the San Andreas fault — one plate is sliding by the other. But at the southern end, along the coast of Haida Gwaii and in particular southern Haida Gwaii, there is a component of convergence. So not only are they moving... side by side, but they're compressing each other." Bostock said the magnitude 7.7 Haida Gwaii earthquake of 2012 led scientists to understand there was a significant component of "under thrusting" or subduction along the fault line. The new research has now mapped it out in greater clarity. At approximately 300 kilometres long, the Queen Charlotte subduction zone is shorter than the 1,000-kilometre-long Cascadia subduction zone that runs from northern Vancouver Island to Northern California. The Cascadia subduction zone is where the "Big One" is expected — that being the oft-forecasted megathrust earthquake predicted to register magnitude 9 or higher. Experts believe it's just a matter of time before the Big One hits considering that stress between the subducting Juan de Fuca plate and the North American plate has been building up since its last major earthquake in the year 1700. In contrast, Bostock believes Haida Gwaii is not susceptible to a megathrust quake anytime soon. "In my opinion it's very unlikely we'd have another megathrust earthquake off Haida Gwaii within the next 100 years. We're not building stress up fast enough for us to have another one like we just experienced 12 years ago," he said. The western coast of Haida Gwaii has been the site of four earthquakes of 7.0 magnitude or more in the past century, including the largest in recorded Canadian history in 1949 that registered 8.1, according to Earthquakes Canada. University of Victoria professor and study co-author Kelin Wang said the new research helps understand and plan for a megathrust. "Certainly it will provide important input for our building codes and the type of ground shaking we would expect, also in terms of tsunami evacuation and preparedness," he said.
Vancouver Sun
11-08-2025
- Science
- Vancouver Sun
Study maps megathrust quake zone off northern B.C., but risk may be far in future
Scientists have captured the first detailed images of the meeting of two tectonic plates off the coast of northern B.C., an area they say has the potential to generate large megathrust earthquakes and tsunamis. The images confirm what appears to be a rare geological occurrence, a subduction zone in its 'infancy,' the study by U.S. and Canadian researchers shows. The paper, in the peer-reviewed journal Science Advances, says the Queen Charlotte plate boundary features the beginnings of such a zone, where one plate slides under the other. Start your day with a roundup of B.C.-focused news and opinion. By signing up you consent to receive the above newsletter from Postmedia Network Inc. A welcome email is on its way. If you don't see it, please check your junk folder. The next issue of Sunrise will soon be in your inbox. Please try again Interested in more newsletters? Browse here. The plate boundary that extends from the southern tip of Haida Gwaii to southeast Alaska was the site of Canada's two largest earthquakes in recent history — a magnitude-8.1 quake in 1949 and the magnitude-7.8 quake in 2012. Co-author Michael Bostock, a professor in the department of earth, ocean and atmospheric sciences at the University of B.C., says it's likely the area will see more such megathrust quakes, and the next one could be larger as the fault grows. The good news for people living on B.C.'s north coast, he says, is that a quake of similar magnitude to the one in 2012 isn't likely again for several hundred years. 'In a sense, the concern is passed, at least for the next few generations of people.' The quake in 1949 was caused by tectonic plates moving side by side along a fault, known as a strike-slip earthquake. These are far less likely to produce tsunamis. The 2012 quake bore hallmarks of subduction, which produces the largest quakes. But until the study published last month, there was no detailed imaging confirming it, says Bostock. 'Megathrust is just a fancy name for a thrust fault, a shallow-dipping thrust fault, where subduction is taking place. So, yes, what we're imaging here is a nascent megathrust.' Recent megathrust earthquakes include last month's 8.8-magnitude quake off the coast of southeast Russia, and the massive quakes that triggered devastating tsunamis off Japan in 2011 and Indonesia in 2004. Before the 2012 quake off Haida Gwaii, researchers had been debating whether subduction was a feature of the Queen Charlotte plate boundary, Bostock says. The quake strongly suggested an 'under-thrusting fault,' and the detailed imaging has confirmed it, he says. 'The geometry of the Haida Gwaii thrust suggests that larger thrust earthquakes could nucleate along the margin and that tsunamis could be more common, both of which substantially increase the hazard of the region,' the paper says. The site is a 'rare example' of the beginnings of subduction, with the imaging 'capturing this fundamental tectonic process in its infancy,' it says. Still, it says the future of the Queen Charlotte plate boundary is uncertain. 'While it has efficiently evolved to its current state, subduction initiation can fail at any stage before self-sustained subduction is reached; thus, the (plate boundary) evolving to this point does not guarantee a future outcome,' the paper says. Bostock says there's debate about how quickly the Pacific plate is moving into the North American plate, but it's somewhere between 0.5 and 2.5 centimetres a year, along a roughly 200-kilometre stretch off the Haida Gwaii coast. By contrast, the Cascadia subduction zone spans about 1,000 kilometres from northern Vancouver Island to northern California, and the tectonic plates are converging at a faster rate, closer to four centimetres a year, he says. The Cascadia zone is expected to produce a massive quake sometime in the next 200 to 500 years — but that's not likely at the Haida Gwaii site, Bostock says. 'So, because it's a smaller fault area, and because the convergence is smaller, something like half as much as it is in Cascadia … we're not likely to have another big (megathrust) earthquake off of Haida Gwaii in the near future.' The relatively smaller size of the fault off Haida Gwaii limits the size of quakes it may produce, Bostock adds. The 7.8 quake in 2012 is 'probably as big as we're likely to get, unless the zone grows bigger,' which it may do over a long period of time, he says. The quake in 2012 rattled much of north-central B.C., including Haida Gwaii, Prince Rupert and Quesnel, and triggered a tsunami warning for coastal areas. It also altered the flow and temperature of culturally important hot springs on a small island in the southeast part of the Haida Gwaii archipelago. Lindsay Worthington, another co-author of the paper, says the site offers a 'natural laboratory' for the study of plate boundaries, describing it as 'one of the only places on the planet' where researchers can observe subduction in its infancy. The images were captured in detail by dragging a 15-kilometre-long hydrophone array behind a ship. 'Without knowing really what the subsurface looks like, there's only so much that you can infer,' says Worthington, a professor in the department of earth and planetary sciences at the University of New Mexico. 'Now that we have these pretty definite geometries … we can have better understanding of what types of events happened in the past, and then that gives you insights into what's possible in the future.' While a giant earthquake is not imminent off Haida Gwaii, Worthington says the Queen Charlotte plate boundary is still 'the largest natural hazard in Canada.'
National Observer
11-08-2025
- Science
- National Observer
Study maps 'megathrust' quake zone off northern BC, but risk likely to be far in future
Scientists have captured the first detailed images of the meeting of two tectonic plates off the coast of northern British Columbia, an area they say has the potential to generate the largest "megathrust" earthquakes and tsunamis. The images confirm what appears to be a rare geological occurrence, a subduction zone in its "infancy," the study by US and Canadian researchers shows. The paper, in the peer-reviewed journal Science Advances, says the Queen Charlotte plate boundary features the beginnings of such a zone, where one plate slides under the other. The plate boundary that extends from the southern tip of Haida Gwaii to southeast Alaska was the site of Canada's two largest earthquakes in recent history — a magnitude-8.1 quake in 1949 and the magnitude-7.8 quake in 2012. Co-author Michael Bostock, a professor in the department of earth, ocean and atmospheric sciences at the University of BC, says it's likely the area will see more "thrust" quakes, and the next one could be larger as the fault grows. The good news for people living on BC's north coast, he says, is that a quake of similar magnitude to the one in 2012 isn't likely for several hundred years. "In a sense, the concern is passed, at least for the next few generations of people." The quake in 1949 was caused by tectonic plates moving side by side along a fault, known as a "strike-slip" earthquake. These are far less likely to produce tsunamis. The 2012 quake, meanwhile, bore hallmarks of subduction, which produces the largest megathrust quakes. But until the study published last month, there was no detailed imaging confirming it, says Bostock. "Megathrust is just a fancy name for a thrust fault, a shallow-dipping thrust fault, where subduction is taking place. So, yes, what we're imaging here is a nascent megathrust." Recent megathrust earthquakes include last month's 8.8-magnitude quake off the coast of southeast Russia, and the massive quakes that triggered devastating tsunamis off Japan in 2011 and Indonesia in 2004. Prior to the 2012 quake off Haida Gwaii, researchers had been debating whether subduction was a feature of the Queen Charlotte plate boundary, Bostock says. The quake strongly suggested an "under-thrusting fault," and the detailed imaging has confirmed it, he says. "The geometry of the Haida Gwaii thrust suggests that larger thrust earthquakes could nucleate along the margin and that tsunamis could be more common, both of which substantially increase the hazard of the region," the paper says. The site is a "rare example" of the beginnings of subduction, with the imaging "capturing this fundamental tectonic process in its infancy," it says. Still, it says the future of the Queen Charlotte plate boundary is uncertain. "While it has efficiently evolved to its current state, subduction initiation can fail at any stage before self-sustained subduction is reached; thus, the (plate boundary) evolving to this point does not guarantee a future outcome," the paper says. Bostock says there's debate about how quickly the Pacific plate is moving into the North American plate, but it's somewhere between 1/2 and 2 1/2 centimetres per year, along a roughly 200-kilometre stretch off the Haida Gwaii coast. By contrast, the Cascadia subduction zone spans about 1,000 kilometres from northern Vancouver Island to northern California, and the tectonic plates are converging at a faster rate, closer to four centimetres per year, he says. The Cascadia zone is expected to produce a massive quake sometime in the next 200 to 500 years — but that's not likely at the Haida Gwaii site, Bostock says. "So, because it's a smaller fault area, and because the convergence is smaller, something like half as much as it is in Cascadia ... we're not likely to have another big (megathrust) earthquake off of Haida Gwaii in the near future." The relatively smaller size of the fault off Haida Gwaii limits the size of quakes it may produce, Bostock adds. The 7.8 quake in 2012 is "probably as big as we're likely to get, unless the zone grows bigger," which it may do over a long period of time, he says. The quake in 2012 rattled much of north-central BC, including Haida Gwaii, Prince Rupert and Quesnel, and triggered a tsunami warning for coastal areas. It also altered the flow and temperature of culturally important hot springs on a small island within the southeast Haida Gwaii archipelago. Lindsay Worthington, another co-author of the paper, says the site offers a "natural laboratory" for the study of plate boundaries, describing it as "one of the only places on the planet" where researchers can observe subduction in its infancy. The images were captured in "unprecedented" detail by dragging a 15-kilometre-long hydrophone array behind a ship. "Without knowing really what the subsurface looks like, there's only so much that you can infer," says Worthington, a professor in the department of earth and planetary sciences at the University of New Mexico. "Now that we have these pretty definite geometries ... we can have better understanding of what types of events happened in the past, and then that gives you insights into what's possible in the future." While a giant earthquake is not imminent off Haida Gwaii, Worthington says the Queen Charlotte plate boundary is still "the largest natural hazard in Canada."
Winnipeg Free Press
11-08-2025
- Science
- Winnipeg Free Press
Study maps ‘megathrust' quake zone off northern B.C., but risk may be far in future
Scientists have captured the first detailed images of the meeting of two tectonic plates off the coast of northern British Columbia, an area they say has the potential to generate the largest 'megathrust' earthquakes and tsunamis. The images confirm what appears to be a rare geological occurrence, a subduction zone in its 'infancy,' the study by U.S. and Canadian researchers shows. The paper, in the peer-reviewed journal Science Advances, says the Queen Charlotte plate boundary features the beginnings of such a zone, where one plate slides under the other. The plate boundary that extends from the southern tip of Haida Gwaii to southeast Alaska was the site of Canada's two largest earthquakes in recent history — a magnitude-8.1 quake in 1949 and the magnitude-7.8 quake in 2012. Co-author Michael Bostock, a professor in the department of earth, ocean and atmospheric sciences at the University of B.C., says it's likely the area will see more 'thrust' quakes, and the next one could be larger as the fault grows. The good news for people living on B.C.'s north coast, he says, is that a quake of similar magnitude to the one in 2012 isn't likely for several hundred years. 'In a sense, the concern is passed, at least for the next few generations of people.' The quake in 1949 was caused by tectonic plates moving side by side along a fault, known as a 'strike-slip' earthquake. These are far less likely to produce tsunamis. The 2012 quake, meanwhile, bore hallmarks of subduction, which produces the largest megathrust quakes. But until the study published last month, there was no detailed imaging confirming it, says Bostock. 'Megathrust is just a fancy name for a thrust fault, a shallow-dipping thrust fault, where subduction is taking place. So, yes, what we're imaging here is a nascent megathrust.' Recent megathrust earthquakes include last month's 8.8-magnitude quake off the coast of southeast Russia, and the massive quakes that triggered devastating tsunamis off Japan in 2011 and Indonesia in 2004. Prior to the 2012 quake off Haida Gwaii, researchers had been debating whether subduction was a feature of the Queen Charlotte plate boundary, Bostock says. The quake strongly suggested an 'under-thrusting fault,' and the detailed imaging has confirmed it, he says. 'The geometry of the Haida Gwaii thrust suggests that larger thrust earthquakes could nucleate along the margin and that tsunamis could be more common, both of which substantially increase the hazard of the region,' the paper says. The site is a 'rare example' of the beginnings of subduction, with the imaging 'capturing this fundamental tectonic process in its infancy,' it says. Still, it says the future of the Queen Charlotte plate boundary is uncertain. 'While it has efficiently evolved to its current state, subduction initiation can fail at any stage before self-sustained subduction is reached; thus, the (plate boundary) evolving to this point does not guarantee a future outcome,' the paper says. Bostock says there's debate about how quickly the Pacific plate is moving into the North American plate, but it's somewhere between 1/2 and 2 1/2 centimetres per year, along a roughly 200-kilometre stretch off the Haida Gwaii coast. By contrast, the Cascadia subduction zone spans about 1,000 kilometres from northern Vancouver Island to northern California, and the tectonic plates are converging at a faster rate, closer to four centimetres per year, he says. The Cascadia zone is expected to produce a massive quake sometime in the next 200 to 500 years — but that's not likely at the Haida Gwaii site, Bostock says. 'So, because it's a smaller fault area, and because the convergence is smaller, something like half as much as it is in Cascadia … we're not likely to have another big (megathrust) earthquake off of Haida Gwaii in the near future.' The relatively smaller size of the fault off Haida Gwaii limits the size of quakes it may produce, Bostock adds. The 7.8 quake in 2012 is 'probably as big as we're likely to get, unless the zone grows bigger,' which it may do over a long period of time, he says. The quake in 2012 rattled much of north-central B.C., including Haida Gwaii, Prince Rupert and Quesnel, and triggered a tsunami warning for coastal areas. It also altered the flow and temperature of culturally important hot springs on a small island within the southeast Haida Gwaii archipelago. Lindsay Worthington, another co-author of the paper, says the site offers a 'natural laboratory' for the study of plate boundaries, describing it as 'one of the only places on the planet' where researchers can observe subduction in its infancy. The images were captured in 'unprecedented' detail by dragging a 15-kilometre-long hydrophone array behind a ship. 'Without knowing really what the subsurface looks like, there's only so much that you can infer,' says Worthington, a professor in the department of earth and planetary sciences at the University of New Mexico. 'Now that we have these pretty definite geometries … we can have better understanding of what types of events happened in the past, and then that gives you insights into what's possible in the future.' While a giant earthquake is not imminent off Haida Gwaii, Worthington says the Queen Charlotte plate boundary is still 'the largest natural hazard in Canada.' This report by The Canadian Press was first published Aug. 11, 2025.
CBC
10-08-2025
- Science
- CBC
Megathrust fault line off Haida Gwaii confirmed through new imaging
Social Sharing Scientists have confirmed that a fault line off the west coast of Haida Gwaii is of the megathrust variety, capable of generating large earthquakes and tsunamis. The conclusion was gleaned through hydrostatic imaging and measurements of the Queen Charlotte Fault where the Pacific tectonic plate meets the North American plate. The finding was published in Science Advances. The images show that instead of the plates sliding horizontally against each other, the Pacific plate is also colliding with and diving under the North American plate, in a process known as subduction. The friction created by subduction is what creates megathrust conditions, according to UBC professor and study co-author Michael Bostock. "For most of its length, the Queen Charlotte plate boundary is very much like the San Andreas fault — one plate is sliding by the other. But at the southern end, along the coast of Haida Gwaii and in particular southern Haida Gwaii, there is a component of convergence. So not only are they moving... side by side, but they're compressing each other." Bostock said the magnitude 7.7 Haida Gwaii earthquake of 2012 led scientists to understand there was a significant component of "under thrusting" or subduction along the fault line. The new research has now mapped it out in greater clarity. At approximately 300 kilometres long, the Queen Charlotte subduction zone is shorter than the 1,000-kilometre-long Cascadia subduction zone that runs from northern Vancouver Island to Northern California. The Cascadia subduction zone is where the "Big One" is expected — that being the oft-forecasted megathrust earthquake predicted to register magnitude 9 or higher. Experts believe it's just a matter of time before the Big One hits considering that stress between the subducting Juan de Fuca plate and the North American plate has been building up since its last major earthquake in the year 1700. In contrast, Bostock believes Haida Gwaii is not susceptible to a megathrust quake anytime soon. "In my opinion it's very unlikely we'd have another megathrust earthquake off Haida Gwaii within the next 100 years. We're not building stress up fast enough for us to have another one like we just experienced 12 years ago," he said. The western coast of Haida Gwaii has been the site of four earthquakes of 7.0 magnitude or more in the past century, including the largest in recorded Canadian history in 1949 that registered 8.1, according to Earthquakes Canada. University of Victoria professor and study co-author Kelin Wang said the new research helps understand and plan for a megathrust.
