explosion · reviewed by a seismologist
M 1.6ml
Earthquake near Coupeville, WA
No earthquake was likely felt in Coupeville in the 24 hours to 10:39 pm PST (06:39 UTC). The last one was M 4.2, 91 km (57 mi) S, at 2:05 pm PDT on 29 September 2026, estimated intensity II (weak) in town; 9,329 felt reports to USGS. Every earthquake near Coupeville
No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.6 explosion was recorded 5 km (3 mi) west-southwest of Coupeville, WA, at 1:09 pm PDT on 6 August 2020 (20:09 UTC), less than 1 km deep.
USGS: 5 km WSW of Coupeville, Washington
72 km (44 mi) NNW of Seattle, WA · 46 km (29 mi) WNW of Marysville, WA
- When
- 1:09 pm PDT on 6 August 2020 ()
- Where
- 5 km (3 mi) west-southwest of Coupeville, WA · earthquakes near Coupeville
- Magnitude
- M 1.6 (ml)
- Depth
- -0.2 km below the surface
- Felt
- no reports yet
- Nearest
- Island County, 8 km SE
- Nearest mapped fault
- Southern Whidbey Island fault, 2 km from its surface trace — near is not the same as on
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2288 days ago
Earthquake alerts for Coupeville, WA
Get a notification in this browser when USGS records an earthquake near Coupeville, WA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 mi) from the epicentre. In Coupeville, 5 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
Likely felt in: Coupeville 5 km, intensity II · Port Townsend 10 km, intensity II. Estimated for each town centre; each link is that town's own record.
USGS catalogues this as explosion, not an earthquake.
How big was it?
This earthquake released about 6.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 2,300,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
- Around the size people start to feel M 3.0 140× the energy of this one
- This earthquake M 1.6 about 6.6 lb of TNT
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.
Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:
- 5.3 Eastern Olympic Peninsula, Washington · 49 km SSW of this epicentre
- 5.0 6 km W of Conway, Washington · 27 km ENE of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 48.2048, -122.7498. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Island County, WA | 8 km (5 mi) | SE | earthquakes near Island County |
| San Juan County, WA | 43 km (26 mi) | NW | earthquakes near San Juan County |
| Kitsap County, WA | 63 km (39 mi) | S | earthquakes near Kitsap County |
| Jefferson County, WA | 73 km (45 mi) | SW | earthquakes near Jefferson County |
| Snohomish County, WA | 75 km (47 mi) | ESE | earthquakes near Snohomish County |
| Skagit County, WA | 76 km (47 mi) | ENE | earthquakes near Skagit County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
52 earthquakes have been recorded within 50 km since this one.
- 1.7 2 km ESE of Burlington, Washington
- 2.2 3 km ESE of Burlington, Washington
- 1.7 12 km ENE of Jamestown, Washington
- 2.2 2 km N of Mount Vernon, Washington
- 1.8 3 km NW of Mount Vernon, Washington
- 2.3 7 km SSE of Coupeville, Washington
- 1.7 6 km NNW of Lofall, Washington
- 2.0 4 km NE of Oak Bay, Canada
- 1.8 5 km S of Hansville, Washington
- 1.6 8 km NE of Jamestown, Washington
- 2.0 7 km NNE of Jamestown, Washington
- 1.8 2 km S of Clear Lake, Washington
- 1.6 4 km WNW of Freeland, Washington
- 1.5 6 km NNW of Lofall, Washington
- 1.6 1 km NNW of Mount Vernon, Washington
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.