QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

5 km ENE of Oso, Washington

· 3.0 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Skagit County 22 kmSnohomish County 28 kmWhatcom County 61 kmIsland County 61 kmKing County 89 kmKitsap County 93 kmSan Juan County 94 kmChelan County 105 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
3.0 km below the surface
Felt
2 reports
Nearest
Skagit County, 22 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1593 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 2 people have reported feeling it to USGS.

How big was it?

This earthquake released about 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 48.2947, -121.8673. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Skagit County, WA 22 km (14 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 61 km (38 mi) S of here earthquakes near Whatcom County
Island County, WA 61 km (38 mi) ENE of here earthquakes near Island County
King County, WA 89 km (56 mi) N of here earthquakes near King County
Kitsap County, WA 93 km (58 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. 1.7 5 km NNE of Oso, Washington
  2. 1.5 3 km SSE of Stanwood, Washington
  3. 1.6 10 km ESE of Hamilton, Washington
  4. 1.6 3 km NNW of Oso, Washington
  5. 1.6 Washington
  6. 3.4 2 km SSE of Stanwood, Washington
  7. 1.6 3 km WNW of Lake Cavanaugh, Washington
  8. 1.6 6 km WSW of Lake Cavanaugh, Washington
  9. 1.6 2 km E of Granite Falls, Washington
  10. 1.7 15 km NE of Lake Cavanaugh, Washington
  11. 1.9 4 km SW of Big Lake, Washington
  12. 1.6 2 km E of Granite Falls, Washington
  13. 2.9 12 km NNE of Hamilton, Washington
  14. 1.9 6 km W of Lake Cavanaugh, Washington
  15. 2.0 15 km SSW of Concrete, 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 18,000 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.