QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

42 km NE of Marblemount, Washington

Yes. A magnitude 1.9 earthquake was recorded 42 km NE of Marblemount, Washington, at 12:15 am PST on 14 December 2021 (08:15 UTC), 9.4 km deep.

· 9.4 km deep · released about 20 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Whatcom County 62 kmSkagit County 67 kmOkanogan County 95 kmSnohomish County 97 kmChelan County 104 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 1.9 (ml)
Depth
9.4 km below the surface
Felt
no reports yet
Nearest
Whatcom County, 62 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 614 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 11 km (7 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 20 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 760,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 540,000× the energy of this one
  3. Around the size people start to feel M 3.0 48× the energy of this one
  4. This earthquake M 1.9 about 20 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.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.6 Near Marblemount, Washington · 41 km SW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 48.7602, -120.9955. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Whatcom County, WA 62 km (39 mi) W earthquakes near Whatcom County
Skagit County, WA 67 km (42 mi) WSW earthquakes near Skagit County
Okanogan County, WA 95 km (59 mi) ESE earthquakes near Okanogan County
Snohomish County, WA 97 km (60 mi) SW earthquakes near Snohomish County
Chelan County, WA 104 km (64 mi) SSE earthquakes near Chelan County
Douglas County, WA 149 km (92 mi) SE earthquakes near Douglas County

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

Aftershocks so far

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

  1. 0.9 46 km SSW of Princeton, Canada
  2. 1.7 1 km WNW of Marblemount, Washington
  3. 2.6 47 km SSW of Princeton, Canada
  4. 2.1 43 km ENE of Marblemount, Washington
  5. 2.1 52 km SSW of Princeton, Canada
  6. 2.1 16 km ENE of Marblemount, Washington
  7. 1.8 46 km ENE of Marblemount, Washington
  8. 1.7 56 km S of Princeton, Canada
  9. 1.7 14 km ENE of Marblemount, Washington
  10. 1.7 54 km S of Princeton, Canada
  11. 1.6 49 km SE of Hope, Canada
  12. 1.7 45 km NW of Winthrop, Washington
  13. 1.9 43 km S of Princeton, Canada
  14. 1.7 61 km SSW of Princeton, Canada
  15. 1.5 34 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.