M5.1 Earthquake 20 km NW of Honchō, Japan — August 18, 2025
2025-08-18 22:19:22 UTC (2025-08-18) · approx. 7:19 AM UTC+9 local
On August 18, 2025 at 22:19 UTC, a magnitude 5.1 intermediate depth earthquake struck 20 km NW of Honchō, Japan, at a depth of 128.4 km and coordinates 42.0330°, 140.5262°. This earthquake was detected by 129 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 400, placing it among routine seismic activity.
Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 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
140.5262°E
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Common Questions
How strong was the magnitude 5.1 earthquake near Honchō, Japan?
The magnitude 5.1 earthquake that struck 20 km NW of Honchō, Japan on August 18, 2025 at 22:19 UTC had a depth of 128.4 km. For context, this was a moderate earthquake that could be widely felt.
Where did the earthquake occur?
The earthquake epicenter was located at 42.0330°, 140.5262°, which is 20 km NW of Honchō, Japan. View all earthquakes in Japan.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 earthquakes can continue for days to weeks 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 5.1 event is significantly smaller than that historical record.
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Authoritative source: USGS event page (event ID: us6000r1yj). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, August 18, 2025). M5.1 Earthquake 20 km NW of Honchō, Japan — August 18, 2025. Retrieved November 4, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000r1yj/