M4.0 Earthquake 20 km SSW of Shima, Japan — August 4, 2023
2023-08-04 22:35:44 UTC (2023-08-04) · approx. 7:35 AM UTC+9 local
On August 4, 2023 at 22:35 UTC, a magnitude 4.0 deep-focus earthquake struck 20 km SSW of Shima, Japan, at a depth of 352.5 km and coordinates 34.1550°, 136.7865°.
Physical scale: An earthquake of magnitude 4.0 releases seismic energy equivalent to roughly 15 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 347 m — a useful intuition for the size of the slip patch on the fault.
Earthquake Details
136.7865°E
Technical Information
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Common Questions
How strong was the magnitude 4.0 earthquake near Shima, Japan?
The magnitude 4.0 earthquake that struck 20 km SSW of Shima, Japan on August 4, 2023 at 22:35 UTC had a depth of 352.5 km. For context, this was a light earthquake commonly felt near the epicenter.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.0 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 4.0 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us6000kzf1). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, August 4, 2023). M4.0 Earthquake 20 km SSW of Shima, Japan — August 4, 2023. Retrieved October 7, 2023 from https://www.earthquaketracker.org/earthquakes/event/us6000kzf1/