QuakeIndex

Earthquake · reviewed by a seismologist

M 2.4ml

4 km SSW of Roosevelt, Washington

· 28 km deep · released about 120 lb of TNT

10 km30 km60 km120 km N Snohomish County 30 kmKing County 43 kmKitsap County 52 kmIsland County 58 kmSkagit County 73 kmPierce County 89 kmMason County 102 kmChelan County 106 kmSan Juan 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 2.4 (ml)
Depth
28 km below the surface
Felt
39 reports · strongest reported intensity III
Nearest
Snohomish County, 30 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2550 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 39 people have reported feeling it to USGS.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 89,000× the energy of this one
  3. Around the size people start to feel M 3.0 7.9× the energy of this one
  4. This earthquake M 2.4 about 120 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 47.8522, -122.0347. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Snohomish County, WA 30 km (19 mi) SW of here earthquakes near Snohomish County
King County, WA 43 km (27 mi) NNW of here earthquakes near King County
Kitsap County, WA 52 km (32 mi) ENE of here earthquakes near Kitsap County
Island County, WA 58 km (36 mi) SE of here earthquakes near Island County
Skagit County, WA 73 km (45 mi) SSW of here earthquakes near Skagit County
Pierce County, WA 89 km (56 mi) N of here earthquakes near Pierce 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 6 km NE of Fall City, Washington
  2. 2.0 6 km E of Lake Marcel-Stillwater, Washington
  3. 2.1 1 km NNE of Bainbridge Island, Washington
  4. 2.7 5 km NE of Fall City, Washington
  5. 1.9 2 km ENE of Granite Falls, Washington
  6. 1.6 5 km NE of Fall City, Washington
  7. 2.3 6 km NE of Fall City, Washington
  8. 2.3 3 km SSW of Clinton, Washington
  9. 1.6 5 km NE of Fall City, Washington
  10. 2.5 6 km NE of Fall City, Washington
  11. 1.7 6 km NE of Fall City, Washington
  12. 3.0 8 km ENE of Fall City, Washington
  13. 1.7 6 km NE of Fall City, Washington
  14. 3.4 9 km NNE of Snoqualmie, Washington
  15. 1.6 2 km E of Snohomish, 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 1,900 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.