QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Friday Harbor, WA

No earthquake was likely felt in Friday Harbor in the 24 hours to 9:26 pm PST (05:26 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 1.7 earthquake was recorded 11 km (7 mi) southeast of Friday Harbor, WA, at 2:05 am PDT on 2 October 2019 (09:05 UTC), 12 km deep.

USGS: 10 km SE of Friday Harbor, Washington

46 km (28 mi) SW of Bellingham, WA · 103 km (64 mi) NNW of Seattle, WA

2:05 am PDT, Oct 2, 2019 · · 12 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N San Juan County 15 kmIsland County 39 kmSkagit County 81 kmClallam County 82 kmJefferson County 86 kmWhatcom County 90 kmKitsap County 94 kmSnohomish County 97 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
2:05 am PDT on 2 October 2019 ()
Where
11 km (7 mi) southeast of Friday Harbor, WA · earthquakes near Friday Harbor
Magnitude
M 1.7 (ml)
Depth
12 km below the surface
Felt
no reports yet
Nearest
San Juan County, 15 km WNW
Nearest mapped fault
Utsalady Point fault, 13 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 610 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 4 km (2 mi) from the epicentre. In Friday Harbor, 11 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, Anacortes, Oak Harbor.

How big was it?

This earthquake released about 11 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 89× the energy of this one
  4. This earthquake M 1.7 about 11 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 4 earthquakes of M5 or more within 50 km:

  1. 6.0 San Juan Islands, Washington · 27 km NNE of this epicentre
  2. 5.5 21 km SSE of Point Roberts, Washington · 38 km N of this epicentre
  3. 5.1 10 km ESE of Salt Spring Island, Canada · 49 km NW of this epicentre
  4. 5.0 6 km W of Conway, Washington · 39 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 48.4672, -122.9148. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan County, WA 15 km (9 mi) WNW earthquakes near San Juan County
Island County, WA 39 km (24 mi) SSE earthquakes near Island County
Skagit County, WA 81 km (50 mi) E earthquakes near Skagit County
Clallam County, WA 82 km (51 mi) WSW earthquakes near Clallam County
Jefferson County, WA 86 km (54 mi) SSW earthquakes near Jefferson County
Whatcom County, WA 90 km (56 mi) ENE earthquakes near Whatcom County

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

Aftershocks so far

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

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

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