M2.3 Earthquake 7 km SSE of Coupeville, Washington — July 31, 2021
2021-07-31 20:50:20 UTC (2021-07-31) · approx. 12:50 PM UTC-8 local
On July 31, 2021 at 20:50 UTC, a magnitude 2.3 shallow crustal earthquake struck 7 km SSE of Coupeville, Washington, at a depth of 28.2 km and coordinates 48.1545°, -122.6668°.
Physical scale: An earthquake of magnitude 2.3 releases seismic energy equivalent to roughly 37.0 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 22 m — a useful intuition for the size of the slip patch on the fault.
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from 1 citizen response to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-122.6668°E
Technical Information
Common Questions
How strong was the magnitude 2.3 earthquake near Coupeville, Washington?
The magnitude 2.3 earthquake that struck 7 km SSE of Coupeville, Washington on July 31, 2021 at 20:50 UTC had a depth of 28.2 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 2.3 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 2.3 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: uw61752132). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2021, July 31, 2021). M2.3 Earthquake 7 km SSE of Coupeville, Washington — July 31, 2021. Retrieved March 9, 2025 from https://www.earthquaketracker.org/earthquakes/event/uw61752132/