QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

1 km SW of Snoqualmie, Washington

· 19 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N King County 3 kmPierce County 57 kmSnohomish County 60 kmKitsap County 62 kmIsland County 94 kmKittitas County 98 kmThurston County 99 kmChelan County 99 kmMason County 102 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
19 km below the surface
Felt
no reports yet
Nearest
King County, 3 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 567 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 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 47.5183, -121.8405. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
King County, WA 3 km (2 mi) N of here earthquakes near King County
Pierce County, WA 57 km (35 mi) NNE of here earthquakes near Pierce County
Snohomish County, WA 60 km (37 mi) S of here earthquakes near Snohomish County
Kitsap County, WA 62 km (39 mi) ESE of here earthquakes near Kitsap County
Island County, WA 94 km (59 mi) SE of here earthquakes near Island County
Kittitas County, WA 98 km (61 mi) WNW of here earthquakes near Kittitas 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. 1.7 1 km WNW of Bonney Lake, Washington
  2. 2.7 4 km E of Lake Marcel-Stillwater, Washington
  3. 1.8 8 km SSW of Sultan, Washington
  4. 2.3 3 km WNW of Duvall, Washington
  5. 1.6 6 km ENE of Mirrormont, Washington
  6. 1.6 6 km W of Wilderness Rim, Washington
  7. 1.5 0 km SSE of Wilderness Rim, Washington
  8. 2.1 5 km SW of Black Diamond, Washington
  9. 1.5 5 km SW of Des Moines, Washington
  10. 1.8 5 km SW of Des Moines, Washington
  11. 1.6 6 km SW of Sultan, Washington
  12. 1.6 Washington
  13. 1.6 Puget Sound region, Washington
  14. 1.5 Washington
  15. 1.8 2 km SSE of Lake Forest Park, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.6 on 2019-07-12 — it released about 15,000 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.