QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

46 km ENE of Marblemount, Washington

· 9.2 km deep · released about 13 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Whatcom County 70 kmSkagit County 73 kmOkanogan County 87 kmChelan County 99 kmSnohomish County 99 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
9.2 km below the surface
Felt
no reports yet
Nearest
Whatcom County, 70 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 534 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 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 48.7300, -120.8900. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Whatcom County, WA 70 km (44 mi) E of here earthquakes near Whatcom County
Skagit County, WA 73 km (45 mi) ENE of here earthquakes near Skagit County
Okanogan County, WA 87 km (54 mi) WNW of here earthquakes near Okanogan County
Chelan County, WA 99 km (61 mi) NNW of here earthquakes near Chelan County
Snohomish County, WA 99 km (62 mi) NE of here earthquakes near Snohomish County
Douglas County, WA 141 km (88 mi) NW of here earthquakes near Douglas 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. 2.6 47 km SSW of Princeton, Canada
  2. 2.1 43 km ENE of Marblemount, Washington
  3. 2.1 52 km SSW of Princeton, Canada
  4. 2.1 16 km ENE of Marblemount, 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.