QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8ml

8 km SSW of Elk Plain, Washington

· 64 km deep · released about 400 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Pierce County 22 kmThurston County 31 kmLewis County 44 kmMason County 70 kmKing County 73 kmKitsap County 76 kmCowlitz County 89 kmGrays Harbor County 107 kmWahkiakum County 107 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
Magnitude
M 2.8 (ml)
Depth
64 km below the surface
Felt
21 reports · strongest reported intensity III
Measured shaking
intensity II (ShakeMap)
Nearest
Pierce County, 22 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3100 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 21 people have reported feeling it to USGS.

How big was it?

This earthquake released about 400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 38,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 27,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.4× the energy of this one
  4. This earthquake M 2.8 about 400 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.

Where

Epicentre 46.9755, -122.4283. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Pierce County, WA 22 km (14 mi) WSW of here earthquakes near Pierce County
Thurston County, WA 31 km (19 mi) E of here earthquakes near Thurston County
Lewis County, WA 44 km (27 mi) N of here earthquakes near Lewis County
Mason County, WA 70 km (44 mi) SE of here earthquakes near Mason County
King County, WA 73 km (45 mi) SW of here earthquakes near King County
Kitsap County, WA 76 km (47 mi) SSE of here earthquakes near Kitsap County

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

Aftershocks so far

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

  1. 1.5 3 km SW of Kapowsin, Washington
  2. 1.7 1 km SE of Kapowsin, Washington
  3. 1.6 6 km WNW of DuPont, Washington
  4. 2.1 6 km NNE of Olympia, Washington
  5. 1.6 6 km SW of La Grande, Washington
  6. 1.5 2 km ESE of Kapowsin, Washington
  7. 1.9 13 km NNE of Mossyrock, Washington
  8. 1.8 2 km E of Kapowsin, Washington
  9. 1.7 9 km SE of Enumclaw, Washington
  10. 1.9 1 km WNW of DuPont, Washington
  11. 1.7 8 km NNW of Olympia, Washington
  12. 1.6 3 km W of Federal Way, Washington
  13. 1.6 15 km NE of Ashford, Washington
  14. 1.8 1 km E of Browns Point, Washington
  15. 1.7 3 km E 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.