M4.2 Earthquake in the Bonin Islands, Japan region — October 1, 2025
2025-10-01 23:02:50 UTC (2025-10-01) · approx. 8:02 AM UTC+9 local
On October 1, 2025 at 23:02 UTC, a magnitude 4.2 deep-focus earthquake struck in the Bonin Islands, Japan region, at a depth of 429.7 km and coordinates 28.4002°, 139.5299°.
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Earthquake Details
139.5299°E
Technical Information
Common Questions
How strong was the magnitude 4.2 earthquake in the Bonin Islands, Japan region?
The magnitude 4.2 earthquake that struck in the Bonin Islands, Japan region on October 1, 2025 at 23:02 UTC had a depth of 429.7 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 4.2 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 4.2 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000re43). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, October 1, 2025). M4.2 Earthquake in the Bonin Islands, Japan region — October 1, 2025. Retrieved December 19, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000re43/