M4.9 Earthquake southeast of the Ryukyu Islands, Japan — September 25, 2022
2022-09-25 12:43:37 UTC (2022-09-25) · approx. 8:43 PM UTC+8 local
On September 25, 2022 at 12:43 UTC, a magnitude 4.9 shallow crustal earthquake struck southeast of the Ryukyu Islands, Japan, at a depth of 10.0 km and coordinates 23.9862°, 127.1114°. This earthquake was detected by 89 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 369, 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
Earthquake Details
127.1114°E
Technical Information
Common Questions
How strong was the magnitude 4.9 earthquake southeast of the Ryukyu Islands, Japan?
The magnitude 4.9 earthquake that struck southeast of the Ryukyu Islands, Japan on September 25, 2022 at 12:43 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 23.9862°, 127.1114°, which is southeast of the Ryukyu Islands, 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.
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Location
Authoritative source: USGS event page (event ID: us7000iaxi). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2022, September 25, 2022). M4.9 Earthquake southeast of the Ryukyu Islands, Japan — September 25, 2022. Retrieved December 3, 2022 from https://www.earthquaketracker.org/earthquakes/event/us7000iaxi/