QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

4 km NE of Woods Creek, Washington

· 8.3 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Snohomish County 17 kmKing County 47 kmSkagit County 65 kmIsland County 66 kmKitsap County 66 kmChelan County 93 kmPierce County 98 kmWhatcom County 104 kmSan Juan County 113 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
8.3 km below the surface
Felt
no reports yet
Nearest
Snohomish County, 17 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 162 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 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 47.9112, -121.8607. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Snohomish County, WA 17 km (11 mi) SSW of here earthquakes near Snohomish County
King County, WA 47 km (29 mi) N of here earthquakes near King County
Skagit County, WA 65 km (40 mi) S of here earthquakes near Skagit County
Island County, WA 66 km (41 mi) ESE of here earthquakes near Island County
Kitsap County, WA 66 km (41 mi) ENE of here earthquakes near Kitsap County
Chelan County, WA 93 km (58 mi) W of here earthquakes near Chelan County

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

Aftershocks so far

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

  1. 1.7 2 km E of Granite Falls, Washington
  2. 1.1 6 km NE of Oso, Washington
  3. 1.2 1 km NW of Lake Marcel-Stillwater, Washington
  4. 1.7 0 km W of Lake Stickney, Washington
  5. 2.1 10 km ENE of Fall City, Washington
  6. 1.1 2 km NW of Lake Marcel-Stillwater, Washington
  7. 0.8 4 km E of Carnation, Washington
  8. 0.5 2 km S of Union Hill-Novelty Hill, Washington
  9. 1.6 3 km WSW of Lake Cavanaugh, Washington
  10. 2.1 4 km NNE of Snoqualmie, Washington
  11. 1.7 2 km NNE of May Creek, Washington
  12. 1.5 5 km SSW of Monroe, Washington
  13. 1.5 2 km E of Granite Falls, Washington
  14. 1.5 2 km WNW of Ames Lake, Washington
  15. 2.2 10 km NNE of Startup, 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 18,000 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.