QuakeIndex

explosion · reviewed by a seismologist

M 1.9ml

Earthquake near Selah, WA

USGS: 7 km ENE of Selah, Washington

13 km (8 mi) NE of Yakima, WA

11:10 am PDT, Apr 20, 2018 · · -0.6 km deep · released about 18 lb of TNT

10 km30 km60 km120 km N Yakima County 34 kmKittitas County 52 kmBenton County 88 kmKlickitat County 94 kmGrant County 95 kmFranklin 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
11:10 am PDT on 20 April 2018 ()
Where
7 km (4 mi) ENE of Selah, WA · earthquakes near Selah
Magnitude
M 1.9 (ml)
Depth
-0.6 km below the surface
Felt
no reports yet
Nearest
Yakima County, 34 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3087 days ago

A magnitude 1.9 earthquake was recorded 7 km (4 mi) ENE of Selah, WA, at 11:10 am PDT on 20 April 2018 (18:10 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Terrace Heights, Yakima, Gleed, Union Gap, West Valley, Ahtanum.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 18 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 5.8 840,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 600,000× the energy of this one
  3. Around the size people start to feel M 3.0 53× the energy of this one
  4. This earthquake M 1.9 about 18 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 46.6850, -120.4502. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yakima County, WA 34 km (21 mi) SW earthquakes near Yakima County
Kittitas County, WA 52 km (32 mi) NNW earthquakes near Kittitas County
Benton County, WA 88 km (55 mi) SE earthquakes near Benton County
Klickitat County, WA 94 km (58 mi) SSW earthquakes near Klickitat County
Grant County, WA 95 km (59 mi) NE earthquakes near Grant County
Franklin County, WA 119 km (74 mi) E earthquakes near Franklin 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 5 km S of Ellensburg, Washington
  2. 1.9 7 km S of Ellensburg, Washington
  3. 1.8 8 km S of Ellensburg, Washington
  4. 1.7 2 km S of Selah, Washington
  5. 1.8 10 km NW of Tampico, Washington
  6. 1.6 Washington
  7. 1.7 7 km ESE of Kittitas, Washington
  8. 1.6 4 km WNW of Summitview, Washington
  9. 1.7 1 km N of Tieton, Washington
  10. 1.9 Washington
  11. 1.6 2 km ENE of Selah, Washington
  12. 1.8 7 km WSW of Thorp, Washington
  13. 1.6 16 km SSW of Harrah, Washington
  14. 1.5 3 km ESE of Selah, Washington
  15. 1.7 3 km E of Selah, 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.