M4.9 Earthquake 93 km N of Tatsugō, Japan — September 11, 2023
2023-09-11 16:46:11 UTC (2023-09-11) · approx. 1:46 AM UTC+9 local
On September 11, 2023 at 16:46 UTC, a magnitude 4.9 shallow crustal earthquake struck 93 km N of Tatsugō, Japan, at a depth of 10.0 km and coordinates 29.2861°, 129.4905°. This earthquake was detected by 69 seismic stations with good 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
129.4905°E
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Common Questions
How strong was the magnitude 4.9 earthquake near Tatsugō, Japan?
The magnitude 4.9 earthquake that struck 93 km N of Tatsugō, Japan on September 11, 2023 at 16:46 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 29.2861°, 129.4905°, which is 93 km N of Tatsugō, 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: us7000kv3u). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, September 11, 2023). M4.9 Earthquake 93 km N of Tatsugō, Japan — September 11, 2023. Retrieved November 18, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kv3u/