M4.2 Earthquake in the Volcano Islands, Japan region — October 31, 2021
2021-10-31 19:18:42 UTC (2021-10-31) · approx. 5:18 AM UTC+10 local
On October 31, 2021 at 19:18 UTC, a magnitude 4.2 intermediate depth earthquake struck in the Volcano Islands, Japan region, at a depth of 136.4 km and coordinates 22.2682°, 143.4739°.
Physical scale: An earthquake of magnitude 4.2 releases seismic energy equivalent to roughly 30 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 476 m — a useful intuition for the size of the slip patch on the fault.

Earthquake Details
143.4739°E
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Common Questions
How strong was the magnitude 4.2 earthquake in the Volcano Islands, Japan region?
The magnitude 4.2 earthquake that struck in the Volcano Islands, Japan region on October 31, 2021 at 19:18 UTC had a depth of 136.4 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 4.2 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 4.2 earthquakes are often felt but rarely cause damage.
Authoritative source: USGS event page (event ID: us7000frh2). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, October 31, 2021). M4.2 Earthquake in the Volcano Islands, Japan region — October 31, 2021. Retrieved January 17, 2024 from https://www.earthquaketracker.org/earthquakes/event/us7000frh2/