QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

0 km SW of Kalama, Washington

· -0.4 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Columbia County 19 kmCowlitz County 26 kmClark County 38 kmWashington County 53 kmWahkiakum County 55 kmMultnomah County 61 kmClatsop County 66 kmSkamania County 70 kmLewis County 74 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 1.8 (ml)
Depth
-0.4 km below the surface
Felt
no reports yet
Nearest
Columbia County, 19 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2358 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 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 46.0017, -122.8533. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Columbia County, OR 19 km (12 mi) ENE of here earthquakes near Columbia County
Cowlitz County, WA 26 km (16 mi) SSW of here earthquakes near Cowlitz County
Clark County, WA 38 km (24 mi) NW of here earthquakes near Clark County
Washington County, OR 53 km (33 mi) NNE of here earthquakes near Washington County
Wahkiakum County, WA 55 km (34 mi) SE of here earthquakes near Wahkiakum County
Multnomah County, OR 61 km (38 mi) NNW of here earthquakes near Multnomah County

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

Aftershocks so far

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

  1. 1.5 2 km SSE of Lewisville, Washington
  2. 1.7 26 km N of Amboy, Washington
  3. 2.0 1 km NNW of Salmon Creek, Washington
  4. 1.6 Washington-Oregon border region
  5. 1.8 2 km N of West Longview, Washington
  6. 1.7 12 km NE of Vernonia, Oregon
  7. 1.5 13 km ENE of Vernonia, Oregon
  8. 1.7 3 km SSW of Yacolt, Washington
  9. 1.9 3 km NNW of West Longview, Washington
  10. 1.7 3 km NNE of Deer Island, Oregon
  11. 1.6 4 km NW of West Longview, Washington
  12. 1.8 1 km ENE of Prescott, Oregon
  13. 1.8 4 km SW of North Portland, Oregon
  14. 1.5 5 km ENE of Lewisville, Washington
  15. 1.7 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.