4.5

M4.5 Earthquake 26 km ESE of Nishinoomote, JapanSeptember 25, 2021

2021-09-25 21:46:37 UTC (2021-09-25) · approx. 6:46 AM UTC+9 local

MagnitudeM4.5(mb)
Time21:46 UTC6:46 AM UTC+9
Depth38.4 kmshallow crustal
Coordinates30.682°, 131.267°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 25, 2021 at 21:46 UTC, a magnitude 4.5 shallow crustal earthquake struck 26 km ESE of Nishinoomote, Japan, at a depth of 38.4 km and coordinates 30.6821°, 131.2671°.

Physical scale: An earthquake of magnitude 4.5 releases seismic energy equivalent to roughly 85 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 767 m — 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 30.68°, 131.27°

Earthquake Details

Magnitude
4.5 mb
Depth
38.4 km
shallow crustal
Location
30.6821°N
131.2671°E

Technical Information

Event ID
us6000fqgg
Event Type
earthquake
Status
✓ Reviewed
Significance
312
Azimuthal Gap
126.0°
Min Station Distance
3.759°
RMS Residual
0.73 sec
Last Updated
2021-12-04 14:28:27 UTC

Common Questions

How strong was the magnitude 4.5 earthquake near Nishinoomote, Japan?

The magnitude 4.5 earthquake that struck 26 km ESE of Nishinoomote, Japan on September 25, 2021 at 21:46 UTC had a depth of 38.4 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 30.6821°, 131.2671°, which is 26 km ESE of Nishinoomote, Japan. View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.5 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 4.5 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000fqgg). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, September 25, 2021). M4.5 Earthquake 26 km ESE of Nishinoomote, JapanSeptember 25, 2021. Retrieved December 4, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000fqgg/