4.7

M4.7 Earthquake 103 km SSW of Ishigaki, Japan — April 14, 2021

2021-04-14 08:22:19 UTC (2021-04-14) · approx. 4:22 PM UTC+8 local

MagnitudeM4.7(mb)
Time08:22 UTC≈ 4:22 PM UTC+8
Depth10.0 kmshallow crustal
Coordinates23.476°, 123.770°
Felt byNo felt reports
Status✓ Reviewed by USGS

On April 14, 2021 at 08:22 UTC, a magnitude 4.7 shallow crustal earthquake struck 103 km SSW of Ishigaki, Japan, at a depth of 10.0 km and coordinates 23.4762°, 123.7697°.

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 23.48°, 123.77°

Earthquake Details

Magnitude
4.7 mb
Depth
10.0 km
shallow crustal
Location
23.4762°N
123.7697°E

Technical Information

Event ID
us6000e1fm
Event Type
earthquake
Status
✓ Reviewed
Significance
340
Azimuthal Gap
88.0°
Min Station Distance
1.206°
RMS Residual
0.87 sec
Last Updated
2021-06-19 21:25:34 UTC

Common Questions

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

The magnitude 4.7 earthquake that struck 103 km SSW of Ishigaki, Japan on April 14, 2021 at 08:22 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Where did the earthquake occur?

The earthquake epicenter was located at 23.4762°, 123.7697°, which is 103 km SSW of Ishigaki, 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: us6000e1fm). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2021, April 14, 2021). M4.7 Earthquake 103 km SSW of Ishigaki, Japan — April 14, 2021. Retrieved June 19, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000e1fm/