M3.9 Earthquake in the Pagan region, Northern Mariana Islands — December 16, 2025
2025-12-16 23:03:51 UTC (2025-12-16) · approx. 9:03 AM UTC+10 local
On December 16, 2025 at 23:03 UTC, a magnitude 3.9 deep-focus earthquake struck in the Pagan region, Northern Mariana Islands, at a depth of 372.7 km and coordinates 18.8732°, 145.3521°.
Physical scale: An earthquake of magnitude 3.9 releases seismic energy equivalent to roughly 11 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 296 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
145.3521°E
Technical Information
Common Questions
How strong was the magnitude 3.9 earthquake in the Pagan region, Northern Mariana Islands?
The magnitude 3.9 earthquake that struck in the Pagan region, Northern Mariana Islands on December 16, 2025 at 23:03 UTC had a depth of 372.7 km. For context, this was a minor earthquake typically detected only by instruments.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.9 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 3.9 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us7000rnpi). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, December 16, 2025). M3.9 Earthquake in the Pagan region, Northern Mariana Islands — December 16, 2025. Retrieved May 24, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000rnpi/