QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

3 km SSW of Big Lake, Washington

· 20 km deep · released about 14 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Skagit County 35 kmIsland County 39 kmSnohomish County 51 kmWhatcom County 60 kmSan Juan County 64 kmKitsap County 87 kmKing County 103 kmJefferson County 113 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
20 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Skagit County, 35 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2515 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 14 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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 48.3763, -122.2603. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Skagit County, WA 35 km (22 mi) WSW of here earthquakes near Skagit County
Island County, WA 39 km (24 mi) NE of here earthquakes near Island County
Snohomish County, WA 51 km (32 mi) NW of here earthquakes near Snohomish County
Whatcom County, WA 60 km (38 mi) SSW of here earthquakes near Whatcom County
San Juan County, WA 64 km (40 mi) ESE of here earthquakes near San Juan County
Kitsap County, WA 87 km (54 mi) NNE of here earthquakes near Kitsap County

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

Aftershocks so far

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

  1. 1.6 0 km S of Big Lake, Washington
  2. 1.7 3 km WSW of Lake Cavanaugh, Washington
  3. 1.7 3 km E of Granite Falls, Washington
  4. 1.6 6 km SSE of Oso, Washington
  5. 1.9 7 km ENE of Port Townsend, Washington
  6. 2.0 6 km SE of Bay View, Washington
  7. 2.2 5 km NE of Oak Harbor, Washington
  8. 1.8 4 km ENE of Granite Falls, Washington
  9. 1.8 6 km WNW of Coupeville, Washington
  10. 2.1 6 km SE of Oso, Washington
  11. 1.7 5 km NNE of Anacortes, Washington
  12. 2.3 5 km N of Anacortes, Washington
  13. 2.5 5 km N of Anacortes, WA
  14. 1.8 3 km ENE of Granite Falls, Washington
  15. 1.9 4 km W of Mount Vernon, 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.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.