QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2ml

Earthquake near Friday Harbor, WA

No earthquake was likely felt in Friday Harbor in the 24 hours to 4:25 am PST (12:25 UTC). The last one was M 3.8, 41 km (25 mi) SE, at 11:35 pm PDT on 1 July 2026, estimated intensity II (weak) in town; 2,030 felt reports to USGS. Every earthquake near Friday Harbor

This page: a magnitude 2.2 earthquake was recorded 16 km (10 mi) south-southeast of Friday Harbor, WA, at 11:35 am PDT on 28 September 2019 (18:35 UTC), 48 km deep.

USGS: 15 km SSE of Friday Harbor, Washington

97 km (61 mi) NNW of Seattle, WA · 50 km (31 mi) SW of Bellingham, WA

11:35 am PDT, Sep 28, 2019 · · 48 km deep · released about 52 lb of TNT

10 km30 km60 km120 km N San Juan County 18 kmIsland County 33 kmClallam County 79 kmJefferson County 81 kmSkagit County 82 kmKitsap County 88 kmWhatcom County 93 kmSnohomish County 94 kmMason County 119 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
11:35 am PDT on 28 September 2019 ()
Where
16 km (10 mi) south-southeast of Friday Harbor, WA · earthquakes near Friday Harbor
Magnitude
M 2.2 (ml)
Depth
48 km below the surface
Felt
no reports yet
Nearest
San Juan County, 18 km NW
Nearest mapped fault
Utsalady Point fault, 7 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 611 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. In Friday Harbor, 16 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.

Earthquakes near other towns within 30 km: Ault Field, Oak Harbor, Anacortes, Coupeville.

How big was it?

This earthquake released about 52 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 290,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 200,000× the energy of this one
  3. Around the size people start to feel M 3.0 18× the energy of this one
  4. This earthquake M 2.2 about 52 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 · 33 km NNE of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 44 km N of this epicentre
  3. 5.0 6 km W of Conway, Washington · 37 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 48.4098, -122.9157. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 18 km (11 mi) NW earthquakes near San Juan County
Island County, WA 33 km (21 mi) SSE earthquakes near Island County
Clallam County, WA 79 km (49 mi) WSW earthquakes near Clallam County
Jefferson County, WA 81 km (50 mi) SW earthquakes near Jefferson County
Skagit County, WA 82 km (51 mi) E earthquakes near Skagit County
Kitsap County, WA 88 km (55 mi) SSE earthquakes near Kitsap County

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

Aftershocks so far

58 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.