M3.9 Earthquake 19 km SSW of Polichnítos, Greece — July 21, 2021
2021-07-21 23:03:46 UTC (2021-07-21) · approx. 1:03 AM UTC+2 local
On July 21, 2021 at 23:03 UTC, a magnitude 3.9 shallow crustal earthquake struck 19 km SSW of Polichnítos, Greece, at a depth of 14.7 km and coordinates 38.9222°, 26.0911°.
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.
Earthquake Details
26.0911°E
Technical Information
Common Questions
How strong was the magnitude 3.9 earthquake near Polichnítos, Greece?
The magnitude 3.9 earthquake that struck 19 km SSW of Polichnítos, Greece on July 21, 2021 at 23:03 UTC had a depth of 14.7 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.
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Understanding This Data
Magnitude 3.9 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us6000exsw). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, July 21, 2021). M3.9 Earthquake 19 km SSW of Polichnítos, Greece — July 21, 2021. Retrieved September 25, 2021 from https://www.earthquaketracker.org/earthquakes/event/us6000exsw/