QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3ml

Earthquake near Tacoma, WA

No earthquake was likely felt in Tacoma in the 24 hours to 5:00 am PST (13:00 UTC). The last one was M 4.2, 27 km (17 mi) NW, at 2:05 pm PDT on 29 September 2026, estimated intensity III (weak) in town; 9,329 felt reports to USGS. Every earthquake near Tacoma

This page: a magnitude 2.3 earthquake was recorded 46 km (28 mi) west-northwest of Tacoma, WA, at 6:22 pm PST on 10 December 2017 (02:22 UTC), less than 1 km deep.

USGS: 10 km NE of Union, Washington

54 km (33 mi) WSW of Seattle, WA · 42 km (26 mi) N of Olympia, WA

6:22 pm PST, Dec 10, 2017 · · -0.2 km deep · released about 77 lb of TNT

Every earthquake near Tacoma Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mason County 15 kmKitsap County 36 kmThurston County 55 kmJefferson County 59 kmGrays Harbor County 71 kmPierce County 76 kmIsland County 86 kmKing County 88 kmClallam County 102 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
6:22 pm PST on 10 December 2017 ()
Where
46 km (28 mi) west-northwest of Tacoma, WA · earthquakes near Tacoma
Magnitude
M 2.3 (ml)
Depth
-0.2 km below the surface
Felt
no reports yet
Nearest
Mason County, 15 km WSW
Nearest mapped fault
Tacoma fault, 5 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 3259 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 Tacoma, 46 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: Allyn, Belfair, Key Center, Shelton, Home, Wauna.

How big was it?

This earthquake released about 77 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 5.8 200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 140,000× the energy of this one
  3. Around the size people start to feel M 3.0 12× the energy of this one
  4. This earthquake M 2.3 about 77 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 540 times the energy of this one.

Before 2016, the USGS record lists 8 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 The 2001 Nisqually, Washington Earthquake · 36 km SE of this epicentre
  2. 6.7 1 km ENE of Dash Point, Washington · 46 km ESE of this epicentre
  3. 6.1 Puget Sound region, Washington · 19 km E of this epicentre
  4. 5.8 Puget Sound area, Washington · 17 km SSE of this epicentre
  5. 5.3 Eastern Olympic Peninsula, Washington · 43 km N 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 47.4157, -122.9995. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mason County, WA 15 km (9 mi) WSW earthquakes near Mason County
Kitsap County, WA 36 km (22 mi) NE earthquakes near Kitsap County
Thurston County, WA 55 km (34 mi) SSE earthquakes near Thurston County
Jefferson County, WA 59 km (36 mi) NW earthquakes near Jefferson County
Grays Harbor County, WA 71 km (44 mi) WSW earthquakes near Grays Harbor County
Pierce County, WA 76 km (47 mi) ESE earthquakes near Pierce 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. 1.7 2 km SE of Manchester, Washington
  2. 1.9 1 km WNW of DuPont, Washington
  3. 2.3 1 km NNE of Enetai, Washington
  4. 2.8 8 km SW of Skokomish, Washington
  5. 1.7 8 km NNW of Olympia, Washington
  6. 1.8 7 km ESE of Quilcene, Washington
  7. 1.7 6 km W of Lofall, Washington
  8. 1.7 3 km E of Home, Washington
  9. 2.2 1 km SE of Bethel, Washington
  10. 2.1 4 km WSW of Seabeck, Washington
  11. 1.6 8 km S of Seabeck, Washington
  12. 1.7 3 km NE of Southworth, Washington
  13. 1.8 1 km WSW of Belfair, Washington
  14. 1.8 2 km SE of Manchester, Washington
  15. 1.7 2 km SSE of Manchester, 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.