5.1

M5.1 Earthquake 138 km S of Honchō, JapanDecember 8, 2025

2025-12-08 19:01:10 UTC (2025-12-08) · approx. 5:01 AM UTC+10 local

MagnitudeM5.1(mb)
Time19:01 UTC5:01 AM UTC+10
Depth31.3 kmshallow crustal
Coordinates40.902°, 143.214°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 8, 2025 at 19:01 UTC, a magnitude 5.1 shallow crustal earthquake struck 138 km S of Honchō, Japan, at a depth of 31.3 km and coordinates 40.9020°, 143.2141°. This earthquake was detected by 96 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

Map showing earthquake epicenter at 40.90°, 143.21°

Earthquake Details

Magnitude
5.1 mb
Depth
31.3 km
shallow crustal
Location
40.9020°N
143.2141°E

Technical Information

Event ID
us7000rmts
Event Type
earthquake
Status
✓ Reviewed
Significance
400
Stations Used
96
Azimuthal Gap
134.0°
Min Station Distance
1.113°
RMS Residual
1.06 sec
Last Updated
2026-03-04 18:45:07 UTC

Common Questions

How strong was the magnitude 5.1 earthquake near Honchō, Japan?

The magnitude 5.1 earthquake that struck 138 km S of Honchō, Japan on December 8, 2025 at 19:01 UTC had a depth of 31.3 km. For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at 40.9020°, 143.2141°, which is 138 km S of Honchō, 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: us7000rmts). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, December 8, 2025). M5.1 Earthquake 138 km S of Honchō, JapanDecember 8, 2025. Retrieved May 24, 2026 from https://www.earthquaketracker.org/earthquakes/event/us7000rmts/