QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

7 km SW of Swede Heaven, Washington

· 13 km deep · released about 15 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Snohomish County 20 kmSkagit County 29 kmIsland County 65 kmWhatcom County 68 kmKing County 83 kmKitsap County 91 kmChelan County 97 kmSan Juan County 101 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
13 km below the surface
Felt
no reports yet
Nearest
Snohomish County, 20 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 464 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 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 48.2337, -121.8020. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Snohomish County, WA 20 km (12 mi) N of here earthquakes near Snohomish County
Skagit County, WA 29 km (18 mi) S of here earthquakes near Skagit County
Island County, WA 65 km (40 mi) E of here earthquakes near Island County
Whatcom County, WA 68 km (42 mi) S of here earthquakes near Whatcom County
King County, WA 83 km (51 mi) N of here earthquakes near King County
Kitsap County, WA 91 km (57 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

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

  1. 1.7 2 km E of Granite Falls, Washington
  2. 1.1 6 km NE of Oso, Washington
  3. 0.7 6 km SSE of Concrete, Washington
  4. 1.6 3 km WSW of Lake Cavanaugh, Washington
  5. 2.6 2 km ENE of Mount Vernon, Washington
  6. 1.7 2 km NNE of May Creek, Washington
  7. 1.5 5 km SSW of Monroe, Washington
  8. 1.9 7 km SSE of Concrete, Washington
  9. 1.5 2 km E of Granite Falls, Washington
  10. 1.9 2 km NNE of Lyman, Washington
  11. 1.7 3 km N of Lyman, Washington
  12. 2.2 2 km N of Lyman, Washington
  13. 2.2 10 km NNE of Startup, Washington
  14. 1.5 2 km ENE of Granite Falls, Washington
  15. 1.6 3 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 15,000 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.