QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1ml

2 km SW of Marietta, Washington

· 16 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N San Juan County 47 kmWhatcom County 57 kmSkagit County 66 kmIsland County 69 kmSnohomish County 101 kmClallam County 120 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 3.1 (ml)
Depth
16 km below the surface
Felt
286 reports · strongest reported intensity IV
Measured shaking
intensity III (ShakeMap)
Nearest
San Juan County, 47 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3288 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 286 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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 48.7742, -122.6072. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
San Juan County, WA 47 km (29 mi) NE of here earthquakes near San Juan County
Whatcom County, WA 57 km (35 mi) W of here earthquakes near Whatcom County
Skagit County, WA 66 km (41 mi) WNW of here earthquakes near Skagit County
Island County, WA 69 km (43 mi) N of here earthquakes near Island County
Snohomish County, WA 101 km (63 mi) NW of here earthquakes near Snohomish County
Clallam County, WA 120 km (75 mi) NE of here earthquakes near Clallam 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. 2.9 8 km NNW of Friday Harbor, Washington
  2. 1.8 8 km NNW of Friday Harbor, Washington
  3. 2.1 8 km NW of Friday Harbor, Washington
  4. 1.7 8 km NNW of Friday Harbor, Washington
  5. 2.5 8 km NNW of Friday Harbor, Washington
  6. 2.2 8 km NNW of Friday Harbor, Washington
  7. 1.7 8 km NNW of Friday Harbor, Washington
  8. 1.7 6 km NNW of Friday Harbor, Washington
  9. 2.4 6 km SW of Bay View, Washington
  10. 2.3 6 km SW of Bay View, Washington
  11. 1.6 3 km WNW of Alger, Washington
  12. 2.2 5 km W of Sumas, Washington
  13. 1.7 7 km N of Ault Field, Washington
  14. 2.4 13 km WNW of Orcas, Washington
  15. 1.7 8 km W of Ault Field, 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.