4.8

M4.8 Earthquake 66 km E of Ōhara, JapanDecember 21, 2023

2023-12-21 16:11:56 UTC (2023-12-21) · approx. 1:11 AM UTC+9 local

MagnitudeM4.8(mwr)
Time16:11 UTC1:11 AM UTC+9
Depth21.0 kmshallow crustal
Coordinates35.144°, 141.115°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 21, 2023 at 16:11 UTC, a magnitude 4.8 shallow crustal earthquake struck 66 km E of Ōhara, Japan, at a depth of 21.0 km and coordinates 35.1443°, 141.1149°. This earthquake was detected by 266 seismic stations with good location accuracy and was assigned a USGS significance rating of 354, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.8 releases seismic energy equivalent to roughly 239 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.2 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 35.14°, 141.11°

Earthquake Details

Magnitude
4.8 mwr
Depth
21.0 km
shallow crustal
Location
35.1443°N
141.1149°E

Technical Information

Event ID
us7000lkpf
Event Type
earthquake
Status
✓ Reviewed
Significance
354
Stations Used
266
Azimuthal Gap
91.0°
Min Station Distance
2.294°
RMS Residual
0.55 sec
Last Updated
2024-02-27 22:57:03 UTC

Common Questions

How strong was the magnitude 4.8 earthquake near Ōhara, Japan?

The magnitude 4.8 earthquake that struck 66 km E of Ōhara, Japan on December 21, 2023 at 16:11 UTC had a depth of 21.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 35.1443°, 141.1149°, which is 66 km E of Ōhara, Japan. View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.8 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 4.8 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000lkpf). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, December 21, 2023). M4.8 Earthquake 66 km E of Ōhara, JapanDecember 21, 2023. Retrieved February 27, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000lkpf/