QuakeIndex

explosion · reviewed by a seismologist

M 1.9ml

Earthquake near Ellensburg, WA

USGS: 3 km WSW of Thorp, Washington

53 km (33 mi) NNW of Yakima, WA · 139 km (86 mi) ESE of Seattle, WA

10:00 am PDT, Oct 7, 2017 · · -0.9 km deep · released about 21 lb of TNT

10 km30 km60 km120 km N Kittitas County 9 kmYakima County 66 kmChelan County 90 kmGrant County 96 kmKing County 98 kmDouglas County 109 kmPierce County 109 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
10:00 am PDT on 7 October 2017 ()
Where
14 km (9 mi) WNW of Ellensburg, WA · earthquakes near Ellensburg
Magnitude
M 1.9 (ml)
Depth
-0.9 km below the surface
Felt
no reports yet
Nearest
Kittitas County, 9 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3281 days ago

A magnitude 1.9 earthquake was recorded 14 km (9 mi) WNW of Ellensburg, WA, at 10:00 am PDT on 7 October 2017 (17:00 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Kittitas, Cle Elum.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 21 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 5.8 710,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 500,000× the energy of this one
  3. Around the size people start to feel M 3.0 45× the energy of this one
  4. This earthquake M 1.9 about 21 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 since 1900 lists no earthquake of M5 or more within 50 km.

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 47.0503, -120.7120. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kittitas County, WA 9 km (5 mi) NNE earthquakes near Kittitas County
Yakima County, WA 66 km (41 mi) S earthquakes near Yakima County
Chelan County, WA 90 km (56 mi) N earthquakes near Chelan County
Grant County, WA 96 km (60 mi) ENE earthquakes near Grant County
King County, WA 98 km (61 mi) WNW earthquakes near King County
Douglas County, WA 109 km (67 mi) NE earthquakes near Douglas County

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

Aftershocks so far

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

  1. 1.7 1 km N of Tieton, Washington
  2. 1.9 Washington
  3. 1.6 2 km ENE of Selah, Washington
  4. 1.8 7 km WSW of Thorp, Washington
  5. 2.1 12 km SW of Nile, Washington
  6. 1.6 10 km SW of Nile, Washington
  7. 2.0 14 km NE of Cliffdell, Washington
  8. 1.5 3 km ESE of Selah, Washington
  9. 1.7 3 km E of Selah, Washington
  10. 1.8 Washington
  11. 1.6 9 km SSW of Ellensburg, Washington
  12. 1.7 3 km W of Thorp, Washington
  13. 2.0 5 km NE of Gleed, Washington
  14. 1.7 4 km ENE of Kittitas, Washington
  15. 1.7 3 km NW of Summitview, 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.