QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

1 km WNW of Mirrormont, Washington

· 9.3 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N King County 14 kmPierce County 47 kmKitsap County 51 kmSnohomish County 68 kmThurston County 85 kmMason County 88 kmIsland County 91 kmLewis County 102 kmKittitas County 108 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
9.3 km below the surface
Felt
no reports yet
Nearest
King County, 14 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 927 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 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 790,000× the energy of this one
  3. Around the size people start to feel M 3.0 70× the energy of this one
  4. This earthquake M 1.8 about 14 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 47.4683, -122.0173. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
King County, WA 14 km (9 mi) W of here earthquakes near King County
Pierce County, WA 47 km (30 mi) NNE of here earthquakes near Pierce County
Kitsap County, WA 51 km (32 mi) ESE of here earthquakes near Kitsap County
Snohomish County, WA 68 km (42 mi) SSW of here earthquakes near Snohomish County
Thurston County, WA 85 km (53 mi) NE of here earthquakes near Thurston County
Mason County, WA 88 km (55 mi) E of here earthquakes near Mason County

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

Aftershocks so far

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

  1. 2.1 7 km ENE of Fall City, Washington
  2. 3.5 9 km NE of Snoqualmie, Washington
  3. 1.8 7 km NE of Fall City, Washington
  4. 1.7 3 km ENE of Buckley, Washington
  5. 1.5 5 km E of Carnation, Washington
  6. 1.6 1 km NE of Mill Creek, Washington
  7. 2.2 3 km SW of Roosevelt, Washington
  8. 1.8 11 km ESE of Enumclaw, Washington
  9. 1.7 0 km NNE of Parkland, Washington
  10. 2.4 5 km ENE of Tanner, Washington
  11. 1.6 1 km SW of Burien, Washington
  12. 1.6 3 km SSE of Issaquah, Washington
  13. 1.7 2 km N of White Center, Washington
  14. 1.6 3 km SSE of Issaquah, Washington
  15. 2.1 3 km SSE of Issaquah, 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 16,000 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.