QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5ml

9 km NE of Snoqualmie, Washington

· 17 km deep · released about 2.8 tons of TNT

10 km30 km60 km120 km N King County 14 kmSnohomish County 51 kmKitsap County 67 kmPierce County 68 kmChelan County 90 kmIsland County 92 kmKittitas County 97 kmSkagit County 99 kmThurston County 110 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 3.5 (ml)
Depth
17 km below the surface
Felt
1316 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
King County, 14 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 516 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1316 people have reported feeling it to USGS.

How big was it?

This earthquake released about 2.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 61,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,900× the energy of this one
  4. This earthquake M 3.5 about 2.8 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 5.8× more

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 47.6003, -121.7538. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
King County, WA 14 km (8 mi) NNE of here earthquakes near King County
Snohomish County, WA 51 km (31 mi) S of here earthquakes near Snohomish County
Kitsap County, WA 67 km (42 mi) E of here earthquakes near Kitsap County
Pierce County, WA 68 km (42 mi) NNE of here earthquakes near Pierce County
Chelan County, WA 90 km (56 mi) WSW of here earthquakes near Chelan County
Island County, WA 92 km (57 mi) SE of here earthquakes near Island County

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

Aftershocks so far

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

  1. 1.5 3 km NNW of Bryn Mawr-Skyway, Washington
  2. 1.7 3 km NNW of Bryn Mawr-Skyway, Washington
  3. 1.5 4 km SW of Skykomish, Washington
  4. 1.6 4 km WSW of Skykomish, Washington
  5. 1.5 1 km NE of Wilburton, Washington
  6. 1.7 0 km W of Beaux Arts Village, Washington
  7. 1.6 10 km ENE of Snoqualmie, Washington
  8. 1.7 4 km S of Monroe, Washington
  9. 1.6 9 km ENE of Snoqualmie, Washington
  10. 2.2 4 km ESE of Enumclaw, Washington
  11. 2.1 10 km NNE of Snoqualmie, Washington
  12. 1.9 1 km NNW of Maple Valley, Washington
  13. 2.8 3 km NE of Fall City, Washington
  14. 1.6 3 km WSW of Sammamish, Washington
  15. 1.9 1 km SSE of Echo Lake, 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 40 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.