Tintina fault may trigger large Yukon earthquake

New satellite data show a long quiet fault in the Yukon may produce a magnitude 7.5 quake, prompting calls for updated hazard planning.

Tintina Fault Signals Potential for Large Yukon Earthquake

A hidden fault in Canada’s Yukon is drawing new attention after researchers mapped an active segment near Dawson City using high-resolution lidar and satellite data. The Tintina Fault runs about 1,000 kilometers from British Columbia to Alaska, and a roughly 130-kilometer portion at Dawson City shows past earthquakes leaving clear scarps and offsets in terrain. The team measured landform shifts across different ages, from 2.6 million-year-old glacial features to 12,000-year-old surfaces, to reconstruct the fault’s recent behavior. They estimate the fault has accumulated about a 6-meter slip deficit since its last major earthquake, based on tectonic strain rates.

The finding highlights how modern surveying tools can reveal seams of danger that were hidden by forests and deposits. It also shows the limits of current hazard maps, since the Tintina is not listed as a separate seismic source in Canada’s national model. Officials will need to balance caution with the uncertainty around how often large ruptures occur on this fault. As scientists seek a paleoseismic trench to date past quakes, communities and engineers face a task: update planning and infrastructure standards before the next quake hits. The lesson is not panic but preparation: science is catching up with risks that have slept for millennia.

Highlights

Science continues to map danger, and that effort is a hinge between knowledge and community resilience.