Recent research suggests that the concealed structural weaknesses in the Yukon, Canada, may be primed to trigger a significant earthquake of at least magnitude 7.5, as outlined in the latest study.
The Tintina Fault, stretching from northeastern British Columbia to central Alaska, has been silently accumulating tension for over 12,000 years. A new investigation previously deemed relatively harmless indicates that it remains very active.
Regrettably, scientists are unable to predict when the next major quake will strike.
“Our findings indicate that the fault is active and continues to build strain,” said Dr. Theron Finley, the lead author of the study published in Geophysical Research Letters, in a statement to BBC Science Focus. “I expect it will eventually rupture again.”
The Tintina Fault is classified as a “right-lateral strike-slip fault,” where two blocks of the Earth’s crust slide horizontally past each other. If one side moves to the right during an earthquake, it’s identified as right-lateral.
Over the ages, one side of the fault has shifted approximately 430 km (270 mi), during a geological period that spanned roughly 560 to 33.9 million years ago, predominantly in the Eocene epoch.
While minor earthquakes occasionally occur in the region, the Tintina Fault has generally been considered dormant.
“There have been small earthquakes in the 3-4 magnitude range detected along or near the Tintina Fault,” Finley noted. “However, nothing has strongly indicated that a larger outbreak is likely.”
This perspective changed when Finley and his team revisited the fault with advanced technology. By integrating satellite surface models with drone-mounted Light Detection and Ranging (LiDAR) data, researchers uncovered hidden seismic activity within the dense Yukon forests.
The landscape revealed cliffs associated with the fault, forming long, narrow terrains created when a quake pushed material to the surface, often collapsing in the process. These features can span dozens or even hundreds of kilometers, but are typically only a few meters tall and wide.
“In the case of the Tintina fault, these features appear as a series of intriguing mounds,” Finley stated.
By dating these surface formations, researchers determined that the fault has ruptured multiple times over the last 2.6 million years, though no significant earthquakes have occurred in the past 12,000 years.
Fortunately, the region is sparsely populated. However, if the fault does rupture, Finley cautioned that major landslides, infrastructure damage, and impacts on nearby communities would be highly probable.
“We want to emphasize that we don’t have a precise sense of how imminent an earthquake is,” he noted. “Our observations indicate it has been a long time since the last significant quake, but there’s no way to know if one is more likely in the near or distant future.”
Finley remarks that the fault has been confirmed as active, and the next step is to better estimate the frequency of large earthquakes in the area. This could help provide a more reliable timeline, even though scientists cannot accurately forecast when the next rupture may happen. Stay tuned.
“Earthquakes don’t necessarily occur on a regular basis, but they can give us a clearer understanding of how often we can expect significant events,” Finley explained. “Regardless, when the Tintina fault finally releases, it won’t be inconsequential.”
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About our experts
Theron Finley is a geologist at the Yukon Geological Survey. He recently obtained a doctorate from the University of Victoria in Canada and has conducted research on active faults in Western Canada, utilizing remote sensing, structural geology, and paleoseismology.
Source: www.sciencefocus.com
