4.7

M4.7 Earthquake 95 km N of Tatsugō, JapanSeptember 8, 2023

2023-09-08 19:32:24 UTC (2023-09-08) · approx. 4:32 AM UTC+9 local

MagnitudeM4.7(mb)
Time19:32 UTC4:32 AM UTC+9
Depth11.9 kmshallow crustal
Coordinates29.297°, 129.450°
Felt byNo felt reports
Status✓ Reviewed by USGS

On September 8, 2023 at 19:32 UTC, a magnitude 4.7 shallow crustal earthquake struck 95 km N of Tatsugō, Japan, at a depth of 11.9 km and coordinates 29.2975°, 129.4500°. This earthquake was detected by 77 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 340, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 4.7 releases seismic energy equivalent to roughly 169 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 1.1 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

Map showing earthquake epicenter at 29.30°, 129.45°

Earthquake Details

Magnitude
4.7 mb
Depth
11.9 km
shallow crustal
Location
29.2975°N
129.4500°E

Technical Information

Event ID
us7000kvk9
Event Type
earthquake
Status
✓ Reviewed
Significance
340
Stations Used
77
Azimuthal Gap
57.0°
Min Station Distance
2.369°
RMS Residual
0.73 sec
Last Updated
2023-11-17 19:47:52 UTC

Common Questions

How strong was the magnitude 4.7 earthquake near Tatsugō, Japan?

The magnitude 4.7 earthquake that struck 95 km N of Tatsugō, Japan on September 8, 2023 at 19:32 UTC had a depth of 11.9 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 29.2975°, 129.4500°, which is 95 km N of Tatsugō, Japan. View all earthquakes in Japan.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.7 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 4.7 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us7000kvk9). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, September 8, 2023). M4.7 Earthquake 95 km N of Tatsugō, JapanSeptember 8, 2023. Retrieved November 17, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kvk9/