QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Mount Vernon, WA

No earthquake was likely felt in Mount Vernon in the 24 hours to 12:55 am PST (08:55 UTC). The last one was M 2.6, 2 km (1 mi) ENE, at 9:17 pm PDT on 11 September 2026, estimated intensity II (weak) in town; 10 felt reports to USGS. Every earthquake near Mount Vernon

This page: a magnitude 1.6 earthquake was recorded 35 km (22 mi) east of Mount Vernon, WA, at 9:39 pm PST on 15 December 2023 (05:39 UTC), less than 1 km deep.

USGS: 10 km ESE of Hamilton, Washington

48 km (30 mi) NNE of Marysville, WA · 101 km (63 mi) NNE of Seattle, WA

9:39 pm PST, Dec 15, 2023 · · -0.3 km deep · released about 8.1 lb of TNT

Every earthquake near Mount Vernon Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Skagit County 4 kmWhatcom County 41 kmSnohomish County 47 kmIsland County 69 kmSan Juan County 91 kmKing County 109 kmKitsap County 109 kmChelan County 115 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
9:39 pm PST on 15 December 2023 ()
Where
35 km (22 mi) east of Mount Vernon, WA · earthquakes near Mount Vernon
Magnitude
M 1.6 (ml)
Depth
-0.3 km below the surface
Felt
no reports yet
Nearest
Skagit County, 4 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1062 days ago

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 Mount Vernon, 35 km away, the estimate is intensity I (not felt). 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.

Earthquakes near other towns within 30 km: Clear Lake, Sedro-Woolley, Big Lake.

How big was it?

This earthquake released about 8.1 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.

  1. Mineral, Virginia 2011 M 5.8 1,900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,300,000× the energy of this one
  3. Around the size people start to feel M 3.0 120× the energy of this one
  4. This earthquake M 1.6 about 8.1 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 3 earthquakes of M5 or more within 50 km:

  1. 5.6 Near Marblemount, Washington · 34 km E of this epicentre
  2. 5.0 6 km W of Conway, Washington · 45 km WSW of this epicentre
  3. 5.0 4 km ENE of Deming, Washington · 47 km NNW 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 48.4710, -121.8638. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Skagit County, WA 4 km (3 mi) NE earthquakes near Skagit County
Whatcom County, WA 41 km (26 mi) N earthquakes near Whatcom County
Snohomish County, WA 47 km (29 mi) S earthquakes near Snohomish County
Island County, WA 69 km (43 mi) WSW earthquakes near Island County
San Juan County, WA 91 km (57 mi) W earthquakes near San Juan County
King County, WA 109 km (68 mi) S earthquakes near King County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

59 earthquakes have been recorded within 50 km since this one.

  1. 1.7 2 km ENE of Granite Falls, Washington
  2. 1.6 8 km NNE of Sedro-Woolley, Washington
  3. 1.7 1 km E of Granite Falls, Washington
  4. 1.8 2 km ESE of Mount Vernon, Washington
  5. 1.5 16 km SE of Glacier, Washington
  6. 2.4 2 km ESE of Mount Vernon, Washington
  7. 2.2 2 km SE of Mount Vernon, Washington
  8. 2.9 2 km ESE of Mount Vernon, Washington
  9. 1.5 3 km N of Lyman, Washington
  10. 1.7 3 km E of Granite Falls, Washington
  11. 1.5 6 km ESE of Glacier, Washington
  12. 1.6 7 km NNE of Sedro-Woolley, Washington
  13. 1.5 3 km E of Granite Falls, Washington
  14. 1.6 17 km SSE of Glacier, Washington
  15. 1.5 15 km NNE of Hamilton, 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.