QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Yakima, WA

USGS: 14 km S of Harrah, Washington

36 km (22 mi) S of Yakima, WA

2:18 pm PDT, Mar 15, 2021 · · -0.7 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Yakima County 26 kmKlickitat County 48 kmBenton County 79 kmKittitas County 96 kmSherman County 98 kmGilliam County 101 kmSkamania County 112 kmMorrow 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
2:18 pm PDT on 15 March 2021 ()
Where
37 km (23 mi) S of Yakima, WA · earthquakes near Yakima
Magnitude
M 1.8 (ml)
Depth
-0.7 km below the surface
Felt
no reports yet
Nearest
Yakima County, 26 km NW
Nearest mapped fault
Toppenish Ridge structures, 2 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2027 days ago

A magnitude 1.8 earthquake was recorded 37 km (23 mi) S of Yakima, WA, at 2:18 pm PDT on 15 March 2021 (21:18 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Toppenish, Wapato, Zillah, Granger.

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.

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 46.2707, -120.5375. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yakima County, WA 26 km (16 mi) NW earthquakes near Yakima County
Klickitat County, WA 48 km (30 mi) SSW earthquakes near Klickitat County
Benton County, WA 79 km (49 mi) E earthquakes near Benton County
Kittitas County, WA 96 km (59 mi) N earthquakes near Kittitas County
Sherman County, OR 98 km (61 mi) S earthquakes near Sherman County
Gilliam County, OR 101 km (63 mi) SSE earthquakes near Gilliam County

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

Aftershocks so far

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

  1. 0.7 7 km W of Ahtanum, Washington
  2. 0.9 22 km SSE of Harrah, Washington
  3. 2.1 12 km SSE of Bickleton, Washington
  4. 1.5 17 km SSE of White Swan, Washington
  5. 3.1 5 km WSW of Harrah, Washington
  6. 2.0 20 km SW of Desert Aire, Washington
  7. 1.6 2 km WNW of Summitview, Washington
  8. 1.7 20 km S of White Swan, Washington
  9. 1.9 0 km SW of Selah, Washington
  10. 1.9 1 km SSW of Selah, Washington
  11. 2.0 8 km SSE of Bickleton, Washington
  12. 1.5 7 km ESE of Tampico, Washington
  13. 1.5 4 km NNW of Summitview, Washington
  14. 1.8 19 km NW of Bickleton, Washington
  15. 1.6 27 km WSW of White Swan, 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.