M4.6 Earthquake 41 km SSE of Kushima, Japan — April 2, 2025
2025-04-02 21:42:52 UTC (2025-04-02) · approx. 6:42 AM UTC+9 local
Aftershock of the M5.2 mainshock.
On April 2, 2025 at 21:42 UTC, a magnitude 4.6 shallow crustal earthquake struck 41 km SSE of Kushima, Japan, at a depth of 35.0 km and coordinates 31.1332°, 131.3969°. This earthquake was detected by 88 seismic stations with good location accuracy and was assigned a USGS significance rating of 326, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 4.6 releases seismic energy equivalent to roughly 120 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 899 m — a useful intuition for the size of the slip patch on the fault.
This earthquake is part of an ongoing aftershock sequence following the magnitude 5.2 mainshock that occurred 12 days ago 48 km E of Nishinoomote, Japan. Since the mainshock, the USGS has recorded 0 aftershocks in this area. Aftershock activity is expected to continue for days to weeks as stresses on surrounding faults redistribute.
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
131.3969°E
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Common Questions
How strong was the magnitude 4.6 earthquake near Kushima, Japan?
The magnitude 4.6 earthquake that struck 41 km SSE of Kushima, Japan on April 2, 2025 at 21:42 UTC had a depth of 35.0 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 31.1332°, 131.3969°, which is 41 km SSE of Kushima, Japan. View all earthquakes in Japan.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.6 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.2 one earlier?
No. This magnitude 4.6 earthquake is an aftershock of the larger magnitude 5.2 mainshock that occurred earlier 48 km E of Nishinoomote, Japan. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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 4.6 event is significantly smaller than that historical record.
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Authoritative source: USGS event page (event ID: us6000q3jg). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, April 2, 2025). M4.6 Earthquake 41 km SSE of Kushima, Japan — April 2, 2025. Retrieved June 9, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000q3jg/