QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

27 km N of Amboy, Washington

· 6.4 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cowlitz County 16 kmClark County 42 kmSkamania County 43 kmLewis County 48 kmColumbia County 52 kmMultnomah County 68 kmWahkiakum County 74 kmWashington County 82 kmThurston County 91 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 (md)
Depth
6.4 km below the surface
Felt
no reports yet
Nearest
Cowlitz County, 16 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 33 days ago

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

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 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× 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 46.1533, -122.4800. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Cowlitz County, WA 16 km (10 mi) ESE of here earthquakes near Cowlitz County
Clark County, WA 42 km (26 mi) N of here earthquakes near Clark County
Skamania County, WA 43 km (27 mi) WNW of here earthquakes near Skamania County
Lewis County, WA 48 km (30 mi) S of here earthquakes near Lewis County
Columbia County, OR 52 km (32 mi) ENE of here earthquakes near Columbia County
Multnomah County, OR 68 km (42 mi) N of here earthquakes near Multnomah County

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

Aftershocks so far

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

  1. 1.3 20 km E of Castle Rock, Washington
  2. 0.2 37 km NNE of Amboy, Washington
  3. 0.5 38 km NNE of Amboy, Washington
  4. 1.5 5 km NNW of Venersborg, Washington
  5. 0.7 5 km SSW of Morton, Washington
  6. 0.6 38 km NNE of Amboy, Washington
  7. 1.7 18 km N of Amboy, Washington
  8. 0.3 32 km NE of Amboy, Washington
  9. 0.7 21 km ESE of Castle Rock, Washington
  10. 1.1 5 km SW of Morton, Washington
  11. 1.5 5 km SSW of Morton, Washington
  12. 1.3 38 km NNE of Amboy, Washington
  13. 1.0 32 km NNE of Amboy, Washington
  14. 0.9 20 km E of Castle Rock, Washington
  15. 0.6 21 km ESE 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.