QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

Earthquake near Seattle, WA

No earthquake was likely felt in Seattle in the 24 hours to 7:13 am PST (15:13 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 2.7 earthquake was recorded 34 km (21 mi) west-southwest of Seattle, WA, at 12:55 pm PST on 23 January 2018 (20:55 UTC), 51 km deep. 10 people have reported feeling it to USGS.

USGS: 5 km W of Gorst, Washington

33 km (21 mi) WSW of Seattle, WA · 33 km (20 mi) W of Burien, WA

12:55 pm PST, Jan 23, 2018 · · 51 km deep · released about 330 lb of TNT

10 km30 km60 km120 km N Kitsap County 16 kmMason County 36 kmJefferson County 65 kmThurston County 66 kmPierce County 70 kmKing County 71 kmIsland County 71 kmGrays Harbor County 92 kmSnohomish County 96 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
12:55 pm PST on 23 January 2018 ()
Where
34 km (21 mi) west-southwest of Seattle, WA · earthquakes near Seattle
Magnitude
M 2.7 (ml)
Depth
51 km below the surface
Felt
10 reports · strongest reported intensity III
Nearest
Kitsap County, 16 km NE
Nearest mapped fault
Seattle fault, 4 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 3129 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Seattle, 34 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: Navy Yard City, Belfair, Erlands Point-Kitsap Lake, Port Orchard, Chico, Rocky Point.

How big was it?

This earthquake released about 330 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 46,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 33,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.9× the energy of this one
  4. This earthquake M 2.7 about 330 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 130 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 · 42 km S of this epicentre
  2. 6.7 1 km ENE of Dash Point, Washington · 35 km SE of this epicentre
  3. 6.1 Puget Sound region, Washington · 14 km S of this epicentre
  4. 5.8 Puget Sound area, Washington · 29 km SSW of this epicentre
  5. 5.3 Eastern Olympic Peninsula, Washington · 35 km NNW 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 47.5247, -122.7732. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kitsap County, WA 16 km (10 mi) NE earthquakes near Kitsap County
Mason County, WA 36 km (22 mi) WSW earthquakes near Mason County
Jefferson County, WA 65 km (40 mi) WNW earthquakes near Jefferson County
Thurston County, WA 66 km (41 mi) S earthquakes near Thurston County
Pierce County, WA 70 km (44 mi) SE earthquakes near Pierce County
King County, WA 71 km (44 mi) E earthquakes near King 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. 1.6 8 km S of Seabeck, Washington
  2. 1.7 3 km NE of Southworth, Washington
  3. 1.8 1 km WSW of Belfair, Washington
  4. 1.8 2 km SE of Manchester, Washington
  5. 2.1 4 km ENE of Dash Point, Washington
  6. 1.7 2 km SSE of Manchester, Washington
  7. 1.6 2 km SE of Manchester, Washington
  8. 1.6 2 km NE of Shoreline, Washington
  9. 2.8 2 km NNW of Fircrest, Washington
  10. 1.7 1 km SE of Keyport, Washington
  11. 1.5 3 km SSE of Des Moines, Washington
  12. 1.8 3 km S of Suquamish, Washington
  13. 1.6 4 km NE of Bainbridge Island, Washington
  14. 1.5 2 km ESE of Manchester, Washington
  15. 1.9 3 km E of Indianola, 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.