QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

11 km ESE of Enumclaw, Washington

· -0.8 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Pierce County 26 kmKing County 36 kmLewis County 76 kmThurston County 78 kmKitsap County 80 kmKittitas County 89 kmSnohomish County 99 kmMason County 102 kmYakima County 115 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
-0.8 km below the surface
Felt
7 reports · strongest reported intensity III
Nearest
Pierce County, 26 km WSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 488 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 7 people have reported feeling it to USGS.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 730,000× the energy of this one
  3. Around the size people start to feel M 3.0 65× the energy of this one
  4. This earthquake M 1.8 about 15 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 47.1627, -121.8520. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Pierce County, WA 26 km (16 mi) ENE of here earthquakes near Pierce County
King County, WA 36 km (23 mi) S of here earthquakes near King County
Lewis County, WA 76 km (47 mi) NNE of here earthquakes near Lewis County
Thurston County, WA 78 km (49 mi) ENE of here earthquakes near Thurston County
Kitsap County, WA 80 km (50 mi) SE of here earthquakes near Kitsap County
Kittitas County, WA 89 km (55 mi) W of here earthquakes near Kittitas County

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

Aftershocks so far

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

  1. 1.6 23 km ENE of Ashford, Washington
  2. 1.6 22 km ENE of Ashford, Washington
  3. 2.3 22 km ENE of Ashford, Washington
  4. 1.6 22 km ENE of Ashford, Washington
  5. 1.6 22 km ENE of Ashford, Washington
  6. 1.5 23 km ENE of Ashford, Washington
  7. 1.6 23 km ENE of Ashford, Washington
  8. 1.6 2 km WSW of Kapowsin, Washington
  9. 1.7 2 km SSW of Kapowsin, Washington
  10. 1.7 3 km NNE of Dash Point, Washington
  11. 1.6 2 km S of Kapowsin, Washington
  12. 2.0 23 km NNE of Packwood, Washington
  13. 1.6 12 km E of Greenwater, Washington
  14. 1.8 1 km NNW of Maple Valley, Washington
  15. 2.0 8 km ESE of Ashford, 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.