QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

2 km SW of Tualatin, Oregon

· -0.4 km deep · released about 16 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Washington County 32 kmMultnomah County 35 kmYamhill County 44 kmClark County 50 kmClackamas County 52 kmMarion County 55 kmColumbia County 67 kmPolk County 71 kmTillamook County 77 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
-0.4 km below the surface
Felt
no reports yet
Nearest
Washington County, 32 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2146 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 16 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 5.8 970,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 680,000× the energy of this one
  3. Around the size people start to feel M 3.0 61× the energy of this one
  4. This earthquake M 1.8 about 16 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 45.3733, -122.7855. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Washington County, OR 32 km (20 mi) SE of here earthquakes near Washington County
Multnomah County, OR 35 km (22 mi) SW of here earthquakes near Multnomah County
Yamhill County, OR 44 km (27 mi) ENE of here earthquakes near Yamhill County
Clark County, WA 50 km (31 mi) SSW of here earthquakes near Clark County
Clackamas County, OR 52 km (32 mi) WNW of here earthquakes near Clackamas County
Marion County, OR 55 km (34 mi) NNW of here earthquakes near Marion County

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

Aftershocks so far

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

  1. 1.9 12 km WNW of Scappoose, Oregon
  2. 1.5 1 km NW of Wilsonville, Oregon
  3. 1.7 6 km ESE of Molalla, Oregon
  4. 1.8 8 km S of Scappoose, Oregon
  5. 1.7 13 km ESE of Scotts Mills, Oregon
  6. 1.7 8 km SE of Molalla, Oregon
  7. 1.6 3 km ESE of Sherwood, Oregon
  8. 2.0 2 km WNW of Molalla, Oregon
  9. 1.7 4 km ESE of Silverton, Oregon
  10. 1.9 3 km NNE of Hubbard, Oregon
  11. 1.7 Washington-Oregon border region
  12. 1.7 5 km SSW of Saint Paul, Oregon
  13. 1.5 7 km ESE of Estacada, Oregon
  14. 1.7 8 km E of Molalla, Oregon
  15. 1.6 8 km SW of Aloha, 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.