QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Irrigon, OR

No earthquake was likely felt in Irrigon in the 24 hours to 4:45 am PST (12:45 UTC). The last one was M 2.0, 15 km (9 mi) E, at 10:24 am PST on 8 January 2026, estimated intensity II (weak) in town. Every earthquake near Irrigon

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 10 km (6 mi) north of Irrigon, OR, at 9:23 am PST on 1 March 2023 (17:23 UTC), less than 1 km deep.

USGS: 10 km N of Irrigon, Oregon

33 km (20 mi) SW of Kennewick, WA

9:23 am PST, Mar 1, 2023 · · -0.3 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Benton County 27 kmMorrow County 63 kmUmatilla County 72 kmFranklin County 75 kmWalla Walla County 82 kmGilliam County 92 kmKlickitat County 102 kmYakima County 111 kmSherman 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
9:23 am PST on 1 March 2023 ()
Where
10 km (6 mi) north of Irrigon, OR · earthquakes near Irrigon
Magnitude
M 1.8 (ml)
Depth
-0.3 km below the surface
Felt
no reports yet
Nearest
Benton County, 27 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1353 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 13 km (8 mi) from the epicentre. In Irrigon, 10 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: Umatilla, Hermiston, Boardman.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 45.9868, -119.4692. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Benton County, WA 27 km (17 mi) N earthquakes near Benton County
Morrow County, OR 63 km (39 mi) S earthquakes near Morrow County
Umatilla County, OR 72 km (45 mi) SE earthquakes near Umatilla County
Franklin County, WA 75 km (47 mi) NE earthquakes near Franklin County
Walla Walla County, WA 82 km (51 mi) ENE earthquakes near Walla Walla County
Gilliam County, OR 92 km (57 mi) SW earthquakes near Gilliam County

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

Aftershocks so far

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

  1. 1.8 11 km W of Highland, Washington
  2. 1.7 12 km ENE of Hermiston, Oregon
  3. 2.0 7 km WNW of Highland, Washington
  4. 1.8 3 km SSW of West Richland, Washington
  5. 1.8 11 km SSW of Tri-Cities, Washington
  6. 2.8 5 km ESE of Benton City, Washington
  7. 2.0 4 km ESE of Umatilla, Oregon
  8. 1.9 4 km ESE of Umatilla, Oregon
  9. 1.7 10 km SW of Kennewick, Washington
  10. 2.0 3 km E of Umatilla, Oregon
  11. 1.6 9 km WNW of Highland, Washington
  12. 1.7 1 km WNW of Highland, Washington
  13. 1.9 16 km ENE of Arlington, Oregon
  14. 2.0 2 km WSW of Burbank, Washington
  15. 1.8 4 km SSE of Kennewick, 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.