QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Ault Field, WA

No earthquake was likely felt in Ault Field in the 24 hours to 8:02 pm PST (04:02 UTC). The last one was M 4.2, 104 km (65 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 Ault Field

This page: a magnitude 2.3 earthquake was recorded 12 km (8 mi) northwest of Ault Field, WA, at 1:24 am PDT on 2 September 2019 (08:24 UTC), 6.8 km deep. 7 people have reported feeling it to USGS.

USGS: 12 km NW of Ault Field, Washington

94 km (58 mi) NNW of Seattle, WA · 45 km (28 mi) SSW of Bellingham, WA

1:24 am PDT, Sep 2, 2019 · · 6.8 km deep · released about 85 lb of TNT

10 km30 km60 km120 km N San Juan County 25 kmIsland County 30 kmSkagit County 73 kmWhatcom County 86 kmJefferson County 86 kmKitsap County 86 kmSnohomish County 86 kmClallam County 87 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
1:24 am PDT on 2 September 2019 ()
Where
12 km (8 mi) northwest of Ault Field, WA · earthquakes near Ault Field
Magnitude
M 2.3 (ml)
Depth
6.8 km below the surface
Felt
7 reports · strongest reported intensity III
Nearest
San Juan County, 25 km WNW
Nearest mapped fault
Utsalady Point fault, 9 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 2554 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 19 km (12 mi) from the epicentre. In Ault Field, 12 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: Oak Harbor 17 km, intensity II · Anacortes 18 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 85 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 5.8 180,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 130,000× the energy of this one
  3. Around the size people start to feel M 3.0 11× the energy of this one
  4. This earthquake M 2.3 about 85 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. 6.0 San Juan Islands, Washington · 32 km N of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 46 km NNW of this epicentre
  3. 5.0 6 km W of Conway, Washington · 29 km ESE 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 48.4088, -122.8030. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 25 km (15 mi) WNW earthquakes near San Juan County
Island County, WA 30 km (18 mi) SSE earthquakes near Island County
Skagit County, WA 73 km (46 mi) E earthquakes near Skagit County
Whatcom County, WA 86 km (53 mi) NE earthquakes near Whatcom County
Jefferson County, WA 86 km (53 mi) SW earthquakes near Jefferson County
Kitsap County, WA 86 km (54 mi) S earthquakes near Kitsap County

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

Aftershocks so far

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

  1. 2.8 6 km E of North Saanich, Canada
  2. 1.7 15 km NW of Orcas, Washington
  3. 1.6 6 km SW of Port Hadlock-Irondale, Washington
  4. 1.9 7 km ENE of Port Townsend, Washington
  5. 2.0 6 km SE of Bay View, Washington
  6. 2.2 5 km NE of Oak Harbor, Washington
  7. 1.8 6 km WNW of Coupeville, Washington
  8. 1.7 8 km NNW of Friday Harbor, Washington
  9. 1.7 5 km NNE of Anacortes, Washington
  10. 2.3 5 km N of Anacortes, Washington
  11. 3.0 6 km NE of Oak Bay, Canada
  12. 2.5 5 km N of Anacortes, WA
  13. 1.9 4 km W of Mount Vernon, Washington
  14. 1.9 6 km WSW of Mount Vernon, Washington
  15. 1.9 7 km NE of Marrowstone, 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.