4.7

M4.7 Earthquake 4 km SE of Fujioka, JapanDecember 17, 2023

2023-12-17 05:11:39 UTC (2023-12-17) · approx. 2:11 PM UTC+9 local

Felt by 24 people across nearby locations.

MagnitudeM4.7(mb)
Time05:11 UTC2:11 PM UTC+9
Depth77.9 kmintermediate depth
Coordinates36.220°, 139.683°
Felt by24DYFI responses
Status✓ Reviewed by USGS

On December 17, 2023 at 05:11 UTC, a magnitude 4.7 intermediate depth earthquake struck 4 km SE of Fujioka, Japan, at a depth of 77.9 km and coordinates 36.2197°, 139.6826°. This earthquake was detected by 82 seismic stations with good location accuracy and was assigned a USGS significance rating of 349, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.7 releases seismic energy equivalent to roughly 169 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.1 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 36.22°, 139.68°

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 24 citizen responses 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 M4.7 earthquake near 4 km SE of Fujioka, Japan

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

Earthquake Details

Magnitude
4.7 mb
Depth
77.9 km
intermediate depth
Location
36.2197°N
139.6826°E
Felt Reports
24
DYFI responses
Community Intensity
3.8
CDI from reports

Technical Information

Event ID
us7000ljmr
Event Type
earthquake
Status
✓ Reviewed
Significance
349
Stations Used
82
Azimuthal Gap
119.0°
Min Station Distance
1.232°
RMS Residual
0.64 sec
Last Updated
2025-09-21 14:50:25 UTC

Common Questions

How strong was the magnitude 4.7 earthquake near Fujioka, Japan?

The magnitude 4.7 earthquake that struck 4 km SE of Fujioka, Japan on December 17, 2023 at 05:11 UTC had a depth of 77.9 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 36.2197°, 139.6826°, which is 4 km SE of Fujioka, Japan. View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.7 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 4.7 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000ljmr). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, December 17, 2023). M4.7 Earthquake 4 km SE of Fujioka, JapanDecember 17, 2023. Retrieved September 21, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000ljmr/