Simply Science in Seconds: Tying seismic science to preparedness in the North

From ancient faults to modern cities, NRCan science is helping the North stand strong against future
earthquakes

March 2026

The seven-second summary:

New research classifying Yukon soils and sediments is helping scientists better predict how the ground beneath Yukon
communities could shake during earthquakes — and what that means for infrastructure and public safety in Canada’s
North. From mapping soil stiffness to revealing ancient faults with modern hazards, this work is improving earthquake
risk assessments.

Recent events

On December 6, 2025, a magnitude 7.0 earthquake struck near the Yukon–Alaska border and was felt in nearby
communities, including Whitehorse and the village of Haines Junction. Scientists from Natural Resources Canada (NRCan)
have been working closely with the Yukon Geological Survey (YGS) in tracking aftershocks and assessing impacts on
infrastructure and communities.

“This recent event confirms for us that our science and research are advancing our understanding of earthquake hazards
in the region. The event was also a reminder of the importance of our research toward understanding how earthquake
shaking changes throughout the territory.”
— Jeremy Gosselin, research scientist, Natural Resources Canada

The sentiment on sediment: Mapping for safety in the Yukon

When an earthquake occurs, ground shaking can vary dramatically depending on soil and sediment types. Typically, the
softer the site, the more intense the shaking. However, the effect is more complicated in the North, where frozen
ground, also called permafrost, can make soft sediments act more rigidly.

In a recently published study, scientists measured the rigidity, or stiffness, of soils at 14 sites in southwestern
Yukon, making their first step in classifying ground conditions for hazard assessments and building codes.

When the ground shakes during an earthquake, rigid soils behave differently than softer ones, which affects how
buildings, highways and community infrastructure respond. This study now provides data that engineers can use to
forecast where shaking may be stronger or weaker, which helps in the design of resilient and safe buildings and
infrastructure.

Ancient faults, modern risk

The soil rigidity work in Yukon builds on NRCan’s broader seismic research in the North. NRCan and YGS have been
working together to better understand earthquake hazards and tectonic activity across the Yukon and Alaskan border
region — including recent seismic research on earthquake activity near the Denali Fault, stretching hundreds of
kilometres across southwestern Yukon along the Alaska Highway.

The region’s seismic potential is underscored by events like the magnitude 7.1 Saint Elias earthquake of February
1979, which struck between southeastern Alaska and the southwestern Yukon. Geologic evidence shows that multiple large
earthquakes have occurred in the region over the last few thousand years. And recent NRCan research mapping the
stresses and deformations of tectonic plates in the region suggests that the fault zone could generate major quakes in
the future.

What this means

These studies together show that:

• The type of soil beneath a community affects how strongly it may shake during an earthquake.
• Long-hidden faults have seismic histories that must be considered for future hazard planning.
• As the climate warms and permafrost thaws, many Yukon sites may experience changes in soil rigidity and hazards may
  increase in those areas.

“Our research is helping Canadians make our communities safer and more resilient,” says Jeremy. “The recent magnitude
7.0 earthquake is also a good reminder that we, as individuals and communities, can take steps to better prepare for
these types of natural hazards.”

If you’re a member of the media or an educator and you would like to learn more about Jeremy and this research,
contact us at: sciencecommunications-communicationsscientifiques@nrcan-rncan.gc.ca