QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

1 km ESE of Union Hill-Novelty Hill, Washington

· 17 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N King County 24 kmSnohomish County 46 kmKitsap County 48 kmPierce County 70 kmIsland County 73 kmSkagit County 92 kmMason County 94 kmThurston County 103 kmChelan County 106 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
17 km below the surface
Felt
no reports yet
Nearest
King County, 24 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1228 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 47.6733, -122.0135. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
King County, WA 24 km (15 mi) NNW of here earthquakes near King County
Snohomish County, WA 46 km (29 mi) SSW of here earthquakes near Snohomish County
Kitsap County, WA 48 km (30 mi) E of here earthquakes near Kitsap County
Pierce County, WA 70 km (43 mi) N of here earthquakes near Pierce County
Island County, WA 73 km (45 mi) SE of here earthquakes near Island County
Skagit County, WA 92 km (57 mi) S of here earthquakes near Skagit County

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

Aftershocks so far

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

  1. 1.6 5 km S of Wilderness Rim, Washington
  2. 1.6 2 km WNW of Mirrormont, Washington
  3. 3.4 13 km E of Lake Marcel-Stillwater, Washington
  4. 1.9 7 km NE of Fall City, Washington
  5. 1.6 2 km SSW of Mirrormont, Washington
  6. 1.7 1 km E of White Center, Washington
  7. 1.6 4 km E of Duvall, Washington
  8. 2.3 2 km E of Issaquah, Washington
  9. 2.0 7 km ENE of Fall City, Washington
  10. 2.6 1 km SSW of Burien, Washington
  11. 2.7 1 km S of Roosevelt, Washington
  12. 1.7 3 km N of West Lake Sammamish, Washington
  13. 1.6 2 km W of City of Sammamish, Washington
  14. 1.6 1 km NE of Mirrormont, Washington
  15. 1.5 1 km E of Granite Falls, 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 14,000 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.