QuakeIndex

explosion · reviewed by a seismologist

M 1.6ml

Earthquake near Mattawa, WA

No earthquake was likely felt in Mattawa in the 24 hours to 6:03 am PST (14:03 UTC). The last one was M 2.3, 16 km (10 mi) SSE, at 7:08 am PDT on 16 April 2025, estimated intensity II (weak) in town. Every earthquake near Mattawa

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.6 explosion was recorded 11 km (7 mi) east-northeast of Mattawa, WA, at 12:14 pm PDT on 20 July 2023 (19:14 UTC), less than 1 km deep.

USGS: 11 km ENE of Mattawa, Washington

12:14 pm PDT, Jul 20, 2023 · · -0.3 km deep · released about 8.4 lb of TNT

10 km30 km60 km120 km N Grant County 54 kmBenton County 63 kmFranklin County 71 kmKittitas County 80 kmYakima County 82 kmAdams County 99 kmDouglas County 108 kmWalla Walla County 114 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
12:14 pm PDT on 20 July 2023 ()
Where
11 km (7 mi) east-northeast of Mattawa, WA · earthquakes near Mattawa
Magnitude
M 1.6 (ml)
Depth
-0.3 km below the surface
Felt
no reports yet
Nearest
Grant County, 54 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1212 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 12 km (7 mi) from the epicentre. In Mattawa, 11 km away, the estimate is intensity II (weak). 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.

Earthquakes near other towns within 30 km: Desert Aire, Royal City.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 8.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,300,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.4 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 46.7685, -119.7652. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Grant County, WA 54 km (34 mi) NNE earthquakes near Grant County
Benton County, WA 63 km (39 mi) SSE earthquakes near Benton County
Franklin County, WA 71 km (44 mi) ESE earthquakes near Franklin County
Kittitas County, WA 80 km (50 mi) WNW earthquakes near Kittitas County
Yakima County, WA 82 km (51 mi) WSW earthquakes near Yakima County
Adams County, WA 99 km (61 mi) ENE earthquakes near Adams County

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

Aftershocks so far

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

  1. 0.3 17 km NW of Benton City, Washington
  2. 2.0 20 km SW of Desert Aire, Washington
  3. 1.7 24 km E of Desert Aire, Washington
  4. 1.6 11 km SE of Desert Aire, Washington
  5. 2.3 11 km SE of Desert Aire, Washington
  6. 1.9 11 km SE of Desert Aire, Washington
  7. 1.6 11 km SE of Desert Aire, Washington
  8. 1.6 11 km SE of Desert Aire, Washington
  9. 2.4 11 km SE of Desert Aire, Washington
  10. 1.9 12 km SE of Desert Aire, Washington
  11. 1.6 12 km SE of Desert Aire, Washington
  12. 1.8 12 km SE of Desert Aire, Washington
  13. 1.7 12 km SE of Desert Aire, Washington
  14. 1.9 12 km SE of Desert Aire, Washington
  15. 1.9 12 km SE of Desert Aire, 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.