QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

3 km NNE of Onalaska, Washington

· 25 km deep · released about 1,200 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lewis County 25 kmThurston County 38 kmCowlitz County 46 kmWahkiakum County 65 kmPierce County 65 kmColumbia County 79 kmPacific County 82 kmSkamania County 87 kmMason County 90 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 3.1 (ml)
Depth
25 km below the surface
Felt
31 reports · strongest reported intensity IV
Nearest
Lewis County, 25 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2136 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 31 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 290,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,100× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.2× more

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 46.6067, -122.7080. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lewis County, WA 25 km (16 mi) W of here earthquakes near Lewis County
Thurston County, WA 38 km (23 mi) SSE of here earthquakes near Thurston County
Cowlitz County, WA 46 km (28 mi) N of here earthquakes near Cowlitz County
Wahkiakum County, WA 65 km (40 mi) ENE of here earthquakes near Wahkiakum County
Pierce County, WA 65 km (40 mi) SW of here earthquakes near Pierce County
Columbia County, OR 79 km (49 mi) NNE of here earthquakes near Columbia County

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

Aftershocks so far

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

  1. 1.8 10 km NE of Castle Rock, Washington
  2. 1.6 9 km NE of Castle Rock, Washington
  3. 1.9 3 km WNW of Winlock, Washington
  4. 1.7 11 km SSW of Morton, Washington
  5. 2.2 11 km SSW of Morton, Washington
  6. 2.0 Washington
  7. 1.5 3 km W of Winlock, Washington
  8. 1.6 15 km E of Castle Rock, Washington
  9. 1.9 14 km WSW of Alder, Washington
  10. 2.1 8 km SSW of Morton, Washington
  11. 2.0 21 km E of Castle Rock, Washington
  12. 1.7 3 km W of Winlock, Washington
  13. 1.5 4 km ESE of Chehalis, Washington
  14. 2.8 21 km E of Castle Rock, Washington
  15. 1.5 21 km E of Castle Rock, 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.