QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4ml

6 km ENE of Oso, Washington

· 3.5 km deep · released about 1.9 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Skagit County 22 kmSnohomish County 28 kmWhatcom County 60 kmIsland County 63 kmKing County 90 kmKitsap County 94 kmSan Juan County 95 kmChelan County 104 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 3.4 (ml)
Depth
3.5 km below the surface
Felt
244 reports · strongest reported intensity IV
Measured shaking
intensity IV (ShakeMap)
Nearest
Skagit County, 22 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1527 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 244 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1.9 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 89,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,800× the energy of this one
  4. This earthquake M 3.4 about 1.9 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4× 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 48.2997, -121.8520. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Skagit County, WA 22 km (13 mi) S of here earthquakes near Skagit County
Snohomish County, WA 28 km (17 mi) NNW of here earthquakes near Snohomish County
Whatcom County, WA 60 km (38 mi) S of here earthquakes near Whatcom County
Island County, WA 63 km (39 mi) ENE of here earthquakes near Island County
King County, WA 90 km (56 mi) N of here earthquakes near King County
Kitsap County, WA 94 km (59 mi) NE of here earthquakes near Kitsap County

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

Aftershocks so far

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

  1. 1.5 3 km SSE of Stanwood, Washington
  2. 1.6 10 km ESE of Hamilton, Washington
  3. 1.6 3 km NNW of Oso, Washington
  4. 1.6 Washington
  5. 3.4 2 km SSE of Stanwood, Washington
  6. 1.6 3 km WNW of Lake Cavanaugh, Washington
  7. 1.6 6 km WSW of Lake Cavanaugh, Washington
  8. 1.6 2 km E of Granite Falls, Washington
  9. 1.7 15 km NE of Lake Cavanaugh, Washington
  10. 1.9 4 km SW of Big Lake, Washington
  11. 1.6 2 km E of Granite Falls, Washington
  12. 2.9 12 km NNE of Hamilton, Washington
  13. 1.9 6 km W of Lake Cavanaugh, Washington
  14. 2.0 15 km SSW of Concrete, Washington
  15. 1.6 2 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 59 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.