M4.6 Earthquake 49 km E of Yokohama, Japan — March 18, 2026
2026-03-18 21:23:02 UTC (2026-03-18) · approx. 6:23 AM UTC+9 local
Felt by 1 person across nearby locations.
On March 18, 2026 at 21:23 UTC, a magnitude 4.6 shallow crustal earthquake struck 49 km E of Yokohama, Japan, at a depth of 66.7 km and coordinates 41.0185°, 141.8326°. This earthquake was detected by 80 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.
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
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
141.8326°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 4.6 earthquake near Yokohama, Japan?
The magnitude 4.6 earthquake that struck 49 km E of Yokohama, Japan on March 18, 2026 at 21:23 UTC had a depth of 66.7 km. For context, this was a light earthquake commonly felt near the epicenter.
Where did the earthquake occur?
The earthquake epicenter was located at 41.0185°, 141.8326°, which is 49 km E of Yokohama, 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.
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.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.
Authoritative source: USGS event page (event ID: us6000sh9j). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2026, March 18, 2026). M4.6 Earthquake 49 km E of Yokohama, Japan — March 18, 2026. Retrieved May 12, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000sh9j/