QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

10 km SE of La Grande, Oregon

· -0.9 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Union County 6 kmBaker County 66 kmUmatilla County 68 kmWallowa County 75 kmGrant County 115 kmColumbia County 116 kmWalla Walla County 117 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
Magnitude
M 1.8 (ml)
Depth
-0.9 km below the surface
Felt
no reports yet
Nearest
Union County, 6 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 936 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

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 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× 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.

Where

Epicentre 45.2508, -118.0135. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Union County, OR 6 km (4 mi) S of here earthquakes near Union County
Baker County, OR 66 km (41 mi) NNW of here earthquakes near Baker County
Umatilla County, OR 68 km (42 mi) ESE of here earthquakes near Umatilla County
Wallowa County, OR 75 km (47 mi) WSW of here earthquakes near Wallowa County
Grant County, OR 115 km (72 mi) NE of here earthquakes near Grant County
Columbia County, WA 116 km (72 mi) S of here earthquakes near Columbia County

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

Aftershocks so far

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

  1. 2.0 2 km NNW of North Powder, Oregon
  2. 1.6 13 km SW of Lostine, Oregon
  3. 1.6 6 km WSW of La Grande, 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.