M4.2 Earthquake 107 km N of Yakutat, Alaska — December 28, 2025
2025-12-28 18:50:49 UTC (2025-12-28) · approx. 9:50 AM UTC-9 local
On December 28, 2025 at 18:50 UTC, a magnitude 4.2 shallow crustal earthquake struck 107 km N of Yakutat, Alaska, at a depth of 8.6 km and coordinates 60.5050°, -139.8644°. The nearest populated place is Haines Junction (population 1,148).
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Population exposure (USGS PAGER)
Estimated population that experienced each level of shaking. Based on the USGS PAGER rapid impact assessment, which combines ShakeMap output with global population grids.
| Shaking intensity (MMI) | Description | Population exposed |
|---|
Earthquake Details
-139.8644°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.2 earthquake near Yakutat, Alaska?
The magnitude 4.2 earthquake that struck 107 km N of Yakutat, Alaska on December 28, 2025 at 18:50 UTC had a depth of 8.6 km. For context, this was a light earthquake commonly felt near the epicenter.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.2 earthquakes can continue for several days and gradually diminish over time.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.
Actions
Understanding This Data
Magnitude 4.2 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us7000rl85). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, December 28, 2025). M4.2 Earthquake 107 km N of Yakutat, Alaska — December 28, 2025. Retrieved May 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000rl85/