QuakeIndex

explosion · reviewed by a seismologist

M 1.6ml

3 km SSW of Kapowsin, Washington

· -0.8 km deep · released about 6.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Pierce County 13 kmLewis County 43 kmThurston County 44 kmKing County 67 kmKitsap County 82 kmMason County 82 kmCowlitz County 91 kmSkamania County 106 kmWahkiakum County 116 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 1.6 (ml)
Depth
-0.8 km below the surface
Felt
no reports yet
Nearest
Pierce County, 13 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3422 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 6.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,400,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.6 about 6.4 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 46.9563, -122.2502. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Pierce County, WA 13 km (8 mi) SW of here earthquakes near Pierce County
Lewis County, WA 43 km (27 mi) NNE of here earthquakes near Lewis County
Thurston County, WA 44 km (27 mi) E of here earthquakes near Thurston County
King County, WA 67 km (42 mi) SSW of here earthquakes near King County
Kitsap County, WA 82 km (51 mi) SSE of here earthquakes near Kitsap County
Mason County, WA 82 km (51 mi) ESE of here earthquakes near Mason County

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

Aftershocks so far

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

  1. 1.7 2 km ESE of Kapowsin, Washington
  2. 2.1 16 km SSE of Carbonado, Washington
  3. 3.0 17 km SSE of Carbonado, Washington
  4. 1.6 3 km SE of Carbonado, Washington
  5. 1.6 3 km NE of Mossyrock, Washington
  6. 2.0 4 km ENE of Ashford, Washington
  7. 1.5 2 km SE of Kapowsin, Washington
  8. 2.4 3 km E of Buckley, Washington
  9. 1.8 1 km NW of Bonney Lake, Washington
  10. 1.8 11 km ESE of Carbonado, Washington
  11. 2.8 8 km SSW of Elk Plain, Washington
  12. 1.7 2 km WNW of Federal Way, Washington
  13. 1.7 4 km SW of Kapowsin, Washington
  14. 1.6 13 km SE of Carbonado, Washington
  15. 1.9 1 km WNW of Bonney Lake, 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.