QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

6 km SW of Clatskanie, Oregon

· -0.3 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Columbia County 20 kmWahkiakum County 28 kmClatsop County 34 kmCowlitz County 48 kmWashington County 58 kmPacific County 68 kmClark County 69 kmTillamook County 78 kmMultnomah County 87 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
-0.3 km below the surface
Felt
no reports yet
Nearest
Columbia County, 20 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1147 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 16 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 5.8 930,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 660,000× the energy of this one
  3. Around the size people start to feel M 3.0 59× the energy of this one
  4. This earthquake M 1.8 about 16 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 46.0633, -123.2687. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Columbia County, OR 20 km (12 mi) NW of here earthquakes near Columbia County
Wahkiakum County, WA 28 km (18 mi) SSE of here earthquakes near Wahkiakum County
Clatsop County, OR 34 km (21 mi) E of here earthquakes near Clatsop County
Cowlitz County, WA 48 km (30 mi) WSW of here earthquakes near Cowlitz County
Washington County, OR 58 km (36 mi) NNW of here earthquakes near Washington County
Pacific County, WA 68 km (42 mi) SE of here earthquakes near Pacific County

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

Aftershocks so far

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

  1. 1.9 2 km WNW of Saint Helens, Oregon
  2. 1.6 3 km E of East Cathlamet, Washington
  3. 1.6 14 km ENE of East Cathlamet, Washington
  4. 1.7 8 km SW of Vernonia, Oregon
  5. 1.5 10 km SSE of Toledo, Washington
  6. 1.9 13 km NW of West Longview, Washington
  7. 1.6 13 km NE of Vernonia, Oregon
  8. 1.6 2 km NNE of Columbia City, Oregon
  9. 1.8 8 km SW of Scappoose, Oregon
  10. 1.9 5 km NW of Westport, Oregon
  11. 1.6 3 km ENE of East Cathlamet, Washington
  12. 1.6 5 km ENE of Prescott, Oregon
  13. 1.6 6 km WSW of Castle Rock, Washington
  14. 1.6 10 km NE of Castle Rock, Washington
  15. 1.6 10 km NE 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

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