QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7ml

1 km WNW of Marblemount, Washington

· 2.1 km deep · released about 12 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Skagit County 26 kmWhatcom County 44 kmSnohomish County 58 kmChelan County 98 kmIsland County 98 kmKing County 119 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 1.7 (ml)
Depth
2.1 km below the surface
Felt
no reports yet
Nearest
Skagit County, 26 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 97 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 12 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 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 5.7 870,000× the energy of this one
  3. Around the size people start to feel M 3.0 78× the energy of this one
  4. This earthquake M 1.7 about 12 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 48.5340, -121.4642. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Skagit County, WA 26 km (16 mi) E of here earthquakes near Skagit County
Whatcom County, WA 44 km (27 mi) SE of here earthquakes near Whatcom County
Snohomish County, WA 58 km (36 mi) NNE of here earthquakes near Snohomish County
Chelan County, WA 98 km (61 mi) NW of here earthquakes near Chelan County
Island County, WA 98 km (61 mi) ENE of here earthquakes near Island County
King County, WA 119 km (74 mi) NNE of here earthquakes near King County

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

Aftershocks so far

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

  1. 1.1 6 km NE of Oso, Washington
  2. 0.7 6 km SSE of Concrete, Washington
  3. 1.8 15 km ESE of Acme, Washington
  4. 1.9 7 km SSE 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.

On USGS

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