3.9

M3.9 Earthquake 81 km SW of Yonakuni, JapanAugust 17, 2024

2024-08-17 18:36:50 UTC (2024-08-17) · approx. 2:36 AM UTC+8 local

MagnitudeM3.9(mwr)
Time18:36 UTC2:36 AM UTC+8
Depth19.2 kmshallow crustal
Coordinates23.913°, 122.472°
Felt byNo felt reports
Status✓ Reviewed by USGS

On August 17, 2024 at 18:36 UTC, a magnitude 3.9 shallow crustal earthquake struck 81 km SW of Yonakuni, Japan, at a depth of 19.2 km and coordinates 23.9135°, 122.4719°.

Physical scale: An earthquake of magnitude 3.9 releases seismic energy equivalent to roughly 11 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 296 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 23.91°, 122.47°

Earthquake Details

Magnitude
3.9 mwr
Depth
19.2 km
shallow crustal
Location
23.9135°N
122.4719°E

Technical Information

Event ID
us7000n7n4
Event Type
earthquake
Status
✓ Reviewed
Significance
234
Stations Used
55
Azimuthal Gap
75.0°
Min Station Distance
0.739°
RMS Residual
0.80 sec
Last Updated
2024-10-26 15:49:18 UTC

Common Questions

How strong was the magnitude 3.9 earthquake near Yonakuni, Japan?

The magnitude 3.9 earthquake that struck 81 km SW of Yonakuni, Japan on August 17, 2024 at 18:36 UTC had a depth of 19.2 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.9 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.9 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000n7n4). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, August 17, 2024). M3.9 Earthquake 81 km SW of Yonakuni, JapanAugust 17, 2024. Retrieved October 26, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000n7n4/