M4.1 Earthquake 89 km E of Onagawa Chō, Japan — May 13, 2025
2025-05-13 16:44:09 UTC (2025-05-13) · approx. 1:44 AM UTC+9 local
On May 13, 2025 at 16:44 UTC, a magnitude 4.1 shallow crustal earthquake struck 89 km E of Onagawa Chō, Japan, at a depth of 28.5 km and coordinates 38.3636°, 142.4686°.
Physical scale: An earthquake of magnitude 4.1 releases seismic energy equivalent to roughly 21 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 406 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 5.1 mainshock that occurred 24 days ago 60 km SE of Ōfunato, 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.
Earthquake Details
142.4686°E
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Common Questions
How strong was the magnitude 4.1 earthquake near Onagawa Chō, Japan?
The magnitude 4.1 earthquake that struck 89 km E of Onagawa Chō, Japan on May 13, 2025 at 16:44 UTC had a depth of 28.5 km. For context, this was a light earthquake commonly felt near the epicenter.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.1 earthquakes can continue for several days and gradually diminish over time.
Is this the same earthquake as the M5.1 one earlier?
No. This magnitude 4.1 earthquake is an aftershock of the larger magnitude 5.1 mainshock that occurred earlier 60 km SE of Ōfunato, Japan. Aftershocks are smaller earthquakes triggered by stress changes from the mainshock.
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Understanding This Data
Magnitude 4.1 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000qgfs). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, May 13, 2025). M4.1 Earthquake 89 km E of Onagawa Chō, Japan — May 13, 2025. Retrieved July 24, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000qgfs/