QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

3 km S of Willapa, Washington

· -0.3 km deep · released about 17 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Pacific County 13 kmWahkiakum County 43 kmGrays Harbor County 54 kmClatsop County 69 kmThurston County 72 kmMason County 87 kmColumbia County 90 kmCowlitz County 91 kmLewis County 99 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
Pacific County, 13 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 271 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 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 46.6417, -123.6700. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Pacific County, WA 13 km (8 mi) NE of here earthquakes near Pacific County
Wahkiakum County, WA 43 km (27 mi) NNW of here earthquakes near Wahkiakum County
Grays Harbor County, WA 54 km (33 mi) SSE of here earthquakes near Grays Harbor County
Clatsop County, OR 69 km (43 mi) N of here earthquakes near Clatsop County
Thurston County, WA 72 km (45 mi) WSW of here earthquakes near Thurston County
Mason County, WA 87 km (54 mi) SSW of here earthquakes near Mason County

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

Aftershocks so far

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

  1. 1.7 1 km E of Oakville, Washington
  2. 1.7 14 km S of Cosmopolis, Washington
  3. 1.8 7 km NNW of Pe Ell, Washington
  4. 1.5 10 km NNE of Tokeland, Washington
  5. 2.4 10 km ESE of Pe Ell, Washington
  6. 1.8 3 km WSW of South Bend, 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.