QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Oak Harbor, WA

No earthquake was likely felt in Oak Harbor in the 24 hours to 2:34 am PST (10:34 UTC). The last one was M 4.2, 99 km (62 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 Oak Harbor

This page: a magnitude 2.3 earthquake was recorded in Oak Harbor, WA, at 9:55 am PDT on 27 May 2021 (16:55 UTC), 21 km deep. 6 people have reported feeling it to USGS.

USGS: 1 km W of Oak Harbor, Washington

78 km (49 mi) NNW of Seattle, WA · 45 km (28 mi) WNW of Marysville, WA

9:55 am PDT, May 27, 2021 · · 21 km deep · released about 94 lb of TNT

10 km30 km60 km120 km N Island County 15 kmSan Juan County 40 kmSkagit County 67 kmSnohomish County 72 kmKitsap County 72 kmJefferson County 84 kmWhatcom County 87 kmClallam County 93 kmKing County 108 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
9:55 am PDT on 27 May 2021 ()
Where
in Oak Harbor, WA · earthquakes near Oak Harbor
Magnitude
M 2.3 (ml)
Depth
21 km below the surface
Felt
6 reports · strongest reported intensity III
Nearest
Island County, 15 km S
Nearest mapped fault
Utsalady Point 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 1898 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. 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: Ault Field, Coupeville, Camano, Port Townsend, Stanwood, Anacortes.

How big was it?

This earthquake released about 94 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 160,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 110,000× the energy of this one
  3. Around the size people start to feel M 3.0 10× the energy of this one
  4. This earthquake M 2.3 about 94 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:

  1. 6.0 San Juan Islands, Washington · 47 km NNW of this epicentre
  2. 5.0 6 km W of Conway, Washington · 18 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 48.2900, -122.6675. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Island County, WA 15 km (9 mi) S earthquakes near Island County
San Juan County, WA 40 km (25 mi) NW earthquakes near San Juan County
Skagit County, WA 67 km (42 mi) ENE earthquakes near Skagit County
Snohomish County, WA 72 km (45 mi) ESE earthquakes near Snohomish County
Kitsap County, WA 72 km (45 mi) S earthquakes near Kitsap County
Jefferson County, WA 84 km (52 mi) SW earthquakes near Jefferson 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. 1.5 8 km ESE of Blyn, Washington
  2. 1.8 3 km W of Hansville, Washington
  3. 2.4 3 km W of Hansville, Washington
  4. 1.8 6 km SSW of Port Ludlow, Washington
  5. 2.3 3 km SSW of Silvana, Washington
  6. 2.4 4 km ENE of Camano, Washington
  7. 1.8 3 km ESE of Port Ludlow, Washington
  8. 1.5 10 km NNW of Anacortes, Washington
  9. 2.0 6 km SSW of Port Ludlow, Washington
  10. 1.8 9 km WSW of Friday Harbor, Washington
  11. 2.1 6 km NNW of La Conner, Washington
  12. 3.6 2 km E of Mount Vernon, Washington
  13. 1.5 3 km NNE of Picnic Point, Washington
  14. 1.9 1 km WNW of Mount Vernon, Washington
  15. 1.8 7 km ESE of Blyn, 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.