M4.0 Earthquake in the Bonin Islands, Japan region — September 16, 2025
2025-09-16 14:30:11 UTC (2025-09-16) · approx. 11:30 PM UTC+9 local
On September 16, 2025 at 14:30 UTC, a magnitude 4.0 deep-focus earthquake struck in the Bonin Islands, Japan region, at a depth of 320.5 km and coordinates 27.2748°, 140.3101°.
Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — a useful intuition for the size of the slip patch on the fault.

Earthquake Details
140.3101°E
Technical Information
Common Questions
How strong was the magnitude 4.0 earthquake in the Bonin Islands, Japan region?
The magnitude 4.0 earthquake that struck in the Bonin Islands, Japan region on September 16, 2025 at 14:30 UTC had a depth of 320.5 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 4.0 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 4.0 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000rfuf). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, September 16, 2025). M4.0 Earthquake in the Bonin Islands, Japan region — September 16, 2025. Retrieved December 3, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000rfuf/