QuakeIndex

explosion · reviewed by a seismologist

M 1.6ml

Earthquake near Pendleton, OR

No earthquake was likely felt in Pendleton in the 24 hours to 3:08 pm PST (23:08 UTC). The last one was M 1.8, 3 km (2 mi) W, at 2:48 pm PDT on 10 September 2026, estimated intensity II (weak) in town. Every earthquake near Pendleton

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.6 explosion was recorded 12 km (7 mi) west of Pendleton, OR, at 3:47 pm PDT on 14 August 2023 (22:47 UTC), less than 1 km deep.

USGS: 11 km W of Pendleton, Oregon

3:47 pm PDT, Aug 14, 2023 · · -0.6 km deep · released about 7.1 lb of TNT

10 km30 km60 km120 km N Umatilla County 18 kmMorrow County 58 kmWalla Walla County 75 kmBenton County 78 kmUnion County 83 kmFranklin County 98 kmColumbia County 106 kmGilliam 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
3:47 pm PDT on 14 August 2023 ()
Where
12 km (7 mi) west of Pendleton, OR · earthquakes near Pendleton
Magnitude
M 1.6 (ml)
Depth
-0.6 km below the surface
Felt
no reports yet
Nearest
Umatilla County, 18 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1187 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 11 km (7 mi) from the epicentre. In Pendleton, 12 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: Mission, Pilot Rock, Stanfield.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 7.1 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 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.1 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 45.6583, -118.9380. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Umatilla County, OR 18 km (11 mi) ESE earthquakes near Umatilla County
Morrow County, OR 58 km (36 mi) WSW earthquakes near Morrow County
Walla Walla County, WA 75 km (47 mi) NNE earthquakes near Walla Walla County
Benton County, WA 78 km (48 mi) NW earthquakes near Benton County
Union County, OR 83 km (52 mi) ESE earthquakes near Union County
Franklin County, WA 98 km (61 mi) N earthquakes near Franklin County

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

Aftershocks so far

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

  1. 1.8 3 km W of Pendleton, Oregon
  2. 1.7 12 km NE of Hermiston, Oregon
  3. 1.5 14 km NE of Hermiston, Oregon
  4. 1.8 4 km SSW of Wallula, Washington
  5. 1.7 4 km ESE of Umatilla, Oregon
  6. 1.7 12 km ENE of Hermiston, Oregon
  7. 2.0 10 km W of Pendleton, Oregon
  8. 2.0 4 km ESE of Umatilla, Oregon
  9. 1.9 4 km ESE of Umatilla, Oregon
  10. 2.3 7 km N of Helix, Oregon
  11. 1.7 8 km N of Helix, Oregon
  12. 1.9 9 km WNW of Touchet, Washington
  13. 1.8 4 km NNW of Pendleton, Oregon
  14. 2.0 3 km E of Umatilla, Oregon
  15. 1.6 4 km S of Echo, Oregon

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.