4.9

M4.9 Earthquake 60 km E of Tomioka, JapanAugust 29, 2025

2025-08-29 16:51:01 UTC (2025-08-29) · approx. 1:51 AM UTC+9 local

Felt by 1 person across nearby locations.

MagnitudeM4.9(mww)
Time16:51 UTC1:51 AM UTC+9
Depth47.8 kmshallow crustal
Coordinates37.296°, 141.700°
Felt by1DYFI response
Status✓ Reviewed by USGS

On August 29, 2025 at 16:51 UTC, a magnitude 4.9 shallow crustal earthquake struck 60 km E of Tomioka, Japan, at a depth of 47.8 km and coordinates 37.2958°, 141.7003°. This earthquake was detected by 68 seismic stations with good location accuracy and was assigned a USGS significance rating of 370, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.9 releases seismic energy equivalent to roughly 338 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.4 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 37.30°, 141.70°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M4.9 earthquake near 60 km E of Tomioka, Japan

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
4.9 mww
Depth
47.8 km
shallow crustal
Location
37.2958°N
141.7003°E
Felt Reports
1
DYFI responses
Community Intensity
2.0
CDI from reports

Technical Information

Event ID
us7000qrw7
Event Type
earthquake
Status
✓ Reviewed
Significance
370
Stations Used
68
Azimuthal Gap
126.0°
Min Station Distance
2.897°
RMS Residual
0.63 sec
Last Updated
2025-11-19 21:59:43 UTC

Common Questions

How strong was the magnitude 4.9 earthquake near Tomioka, Japan?

The magnitude 4.9 earthquake that struck 60 km E of Tomioka, Japan on August 29, 2025 at 16:51 UTC had a depth of 47.8 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 37.2958°, 141.7003°, which is 60 km E of Tomioka, Japan. View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.9 earthquakes can continue for several days 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 4.9 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000qrw7). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, August 29, 2025). M4.9 Earthquake 60 km E of Tomioka, JapanAugust 29, 2025. Retrieved November 19, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000qrw7/