QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

Earthquake near Seattle, WA

No earthquake was likely felt in Seattle in the 24 hours to 2:36 am PST (10:36 UTC). The last one was M 4.2, 37 km (23 mi) SW, at 2:05 pm PDT on 29 September 2026, estimated intensity III (weak) in town; 9,329 felt reports to USGS. Every earthquake near Seattle

This page: a magnitude 1.7 earthquake was recorded 24 km (15 mi) west-southwest of Seattle, WA, at 6:55 pm PDT on 8 May 2021 (01:55 UTC), 14 km deep.

USGS: Puget Sound region, Washington

23 km (15 mi) SW of Seattle, WA · 20 km (12 mi) W of Burien, WA

6:55 pm PDT, May 8, 2021 · · 14 km deep · released about 11 lb of TNT

10 km30 km60 km120 km N Kitsap County 16 kmMason County 46 kmKing County 58 kmPierce County 60 kmThurston County 65 kmIsland County 74 kmJefferson County 77 kmSnohomish County 88 kmGrays Harbor County 101 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
6:55 pm PDT on 8 May 2021 ()
Where
24 km (15 mi) west-southwest of Seattle, WA · earthquakes near Seattle
Magnitude
M 1.7 (ml)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Kitsap County, 16 km NNW
Nearest mapped fault
Seattle fault, 6 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 2013 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 Seattle, 24 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: Bethel, East Port Orchard, Parkwood, Port Orchard, Navy Yard City, Bremerton.

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 5.7 970,000× the energy of this one
  3. Around the size people start to feel M 3.0 86× 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

The largest earthquake within 50 km since 2016 was M 4.1 on 2017-02-23 — about 3,700 times the energy of this one.

Before 2016, the USGS record lists 6 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 The 2001 Nisqually, Washington Earthquake · 40 km SSW of this epicentre
  2. 6.7 1 km ENE of Dash Point, Washington · 24 km SE of this epicentre
  3. 6.1 Puget Sound region, Washington · 15 km SW of this epicentre
  4. 5.8 Puget Sound area, Washington · 33 km SW of this epicentre
  5. 5.3 Eastern Olympic Peninsula, Washington · 45 km NW 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 47.4988, -122.6075. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kitsap County, WA 16 km (10 mi) NNW earthquakes near Kitsap County
Mason County, WA 46 km (28 mi) WSW earthquakes near Mason County
King County, WA 58 km (36 mi) E earthquakes near King County
Pierce County, WA 60 km (38 mi) SE earthquakes near Pierce County
Thurston County, WA 65 km (40 mi) SSW earthquakes near Thurston County
Island County, WA 74 km (46 mi) N earthquakes near Island County

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

Aftershocks so far

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

  1. 1.6 1 km SW of Bothell East, Washington
  2. 1.9 6 km N of Brinnon, Washington
  3. 1.7 3 km WNW of Gorst, Washington
  4. 1.5 1 km WSW of Silverdale, Washington
  5. 1.5 2 km WNW of Gig Harbor, Washington
  6. 1.8 4 km SSW of Port Ludlow, Washington
  7. 1.6 6 km SW of Des Moines, Washington
  8. 1.9 1 km ESE of Esperance, Washington
  9. 1.6 7 km WNW of Gorst, Washington
  10. 1.5 7 km ENE of Allyn, Washington
  11. 1.8 5 km N of Lofall, Washington
  12. 1.5 3 km NNE of White Center, Washington
  13. 1.7 1 km NNE of Enetai, Washington
  14. 1.7 0 km NNE of Navy Yard City, Washington
  15. 1.9 4 km NE of Home, 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.