On December 6, 2025, a magnitude 7.0 earthquake struck the St. Elias Mountains, impacting the region around Hubbard Glacier. This seismic event unleashed a cascade of landslides and avalanches, dramatically altering the frozen landscape.
Satellite Observations of Geological Changes
The NISAR (NASA-ISRO Synthetic Aperture Radar) satellite provided crucial insights into the aftermath of the earthquake. On December 8, just two days post-quake, radar imagery revealed significant alterations in the terrain, with rougher surfaces indicating the presence of debris from the landslides and avalanches. These changes were particularly evident in false-color images, where areas of increased roughness appeared bright, contrasting with smoother surfaces that reflected less radar energy and appeared dark.
Magnitude and Impact of Landslides
Geophysicist Eric Fielding from NASA’s Jet Propulsion Laboratory noted the challenges in mapping ground displacement in this glaciated area, where a layer of ice over 700 meters (2,000 feet) thick obscures the underlying geology. Instead, the evidence of the earthquake’s impact lay atop the ice, with debris from landslides and avalanches scattered across the glacier.
Glaciologist Alex Gardner remarked on the astonishing number of avalanches and landslides observed, with a preliminary analysis from the U.S. Geological Survey identifying over 700 potential landslides and snow avalanches, particularly concentrated northwest of the earthquake’s epicenter.
Ongoing Monitoring and Future Implications
Follow-up assessments by the Yukon Geological Survey on December 12 revealed that some slopes remained unstable, with dust still visible in the air. The debris deposited on the glacier is expected to be transported toward the ocean, aided by the glaciers’ natural flow. Notably, a tributary glacier north of Mount King George, which had previously been sluggish, entered a rapid movement phase, now advancing at speeds of up to 6,000 meters per year (approximately 50 feet per day).
While the region is uninhabited, the changes pose potential hazards for mountaineers and expeditions, as noted in a December 18 update from the USGS. The town of Yakutat, Alaska, located about 90 kilometers (56 miles) south of the epicenter, serves as a common staging area for exploration in the region. The ongoing observations from NISAR are expected to enhance future natural disaster response efforts.
This article was produced by NeonPulse.today using human and AI-assisted editorial processes, based on publicly available information. Content may be edited for clarity and style.
