M5.1 Earthquake 140 km SE of Hasaki, Japan — December 21, 2025
2025-12-21 06:58:47 UTC (2025-12-21) · approx. 3:58 PM UTC+9 local
On December 21, 2025 at 06:58 UTC, a magnitude 5.1 shallow crustal earthquake struck 140 km SE of Hasaki, Japan, at a depth of 10.0 km and coordinates 34.7697°, 141.8354°. This earthquake was detected by 66 seismic stations with good location accuracy and was assigned a USGS significance rating of 400, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 km — a useful intuition for the size of the slip patch on the fault.
The epicenter is located in Japan, a region characterized by the intersection of four tectonic plates — Pacific, Philippine Sea, Eurasian, and North American — creating multiple subduction zones. The nearest mapped fault system is the Japan Trench. View all earthquakes in Japan.
Learn more: Magnitude scale · Aftershock sequences
Earthquake Details
141.8354°E
Technical Information
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Common Questions
How strong was the magnitude 5.1 earthquake near Hasaki, Japan?
The magnitude 5.1 earthquake that struck 140 km SE of Hasaki, Japan on December 21, 2025 at 06:58 UTC had a depth of 10.0 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 34.7697°, 141.8354°, which is 140 km SE of Hasaki, Japan. View all earthquakes in Japan.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 earthquakes can continue for days to weeks and gradually diminish over time.
Has Japan had earthquakes this big before?
The largest recorded earthquake in Japan was the M9.1 Tohoku earthquake of March 11, 2011. Today's magnitude 5.1 event is significantly smaller than that historical record.
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.
Authoritative source: USGS event page (event ID: us6000rwaw). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, December 21, 2025). M5.1 Earthquake 140 km SE of Hasaki, Japan — December 21, 2025. Retrieved May 23, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000rwaw/