A geologic fault that spans across Yukon, Canada, and Alaska could produce a major earthquake after 12 millennia of relative inactivity. Scientists have identified an 81-mile-long segment of the Tintina fault that produced multiple large earthquakes far more recently than previously thought.
Researchers used high-resolution topographic data to scan the area near the Tintina for fault scarps, which form when earthquakes rupture Earth’s surface. They found a series of fault scarps within 12 miles of Dawson City, home to over 1,500 people. By observing landforms left by glacial incursions that occurred 12,000, 132,000, and 2.6 million years ago, the team determined that the Tintina has produced multiple large earthquakes over the last 2.6 million years.
However, a 12,000-year-old landform was not offset by the fault, indicating no major rupture since then. The study found that the Tintina has been accumulating strain at a rate of about 0.2 to 0.8 millimeters per year, with a total slip deficit of approximately 20 feet.
While scientists cannot predict when the next earthquake will occur, the possibility of a major quake warrants some reconsideration of seismic hazard in Northwestern Canada. The nation’s National Seismic Hazard Model does not currently recognize the Tintina as a discrete seismogenic fault source, but researchers plan to integrate their findings into the model and share them with local governments and emergency managers to improve earthquake preparedness.
Source: https://gizmodo.com/sleeping-giant-fault-under-canada-shows-major-earthquake-potential-2000638002