QuakeIndex

explosion · reviewed by a seismologist

M 1.5ml

4 km SSW of Aloha, Oregon

· -0.4 km deep · released about 5.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Washington County 20 kmMultnomah County 38 kmYamhill County 41 kmClark County 47 kmColumbia County 56 kmClackamas County 63 kmMarion County 66 kmTillamook County 69 kmPolk County 74 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 1.5 (ml)
Depth
-0.4 km below the surface
Felt
no reports yet
Nearest
Washington County, 20 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 472 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 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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.

Where

Epicentre 45.4543, -122.8808. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Washington County, OR 20 km (13 mi) ESE of here earthquakes near Washington County
Multnomah County, OR 38 km (23 mi) WSW of here earthquakes near Multnomah County
Yamhill County, OR 41 km (26 mi) NE of here earthquakes near Yamhill County
Clark County, WA 47 km (29 mi) SW of here earthquakes near Clark County
Columbia County, OR 56 km (35 mi) SSE of here earthquakes near Columbia County
Clackamas County, OR 63 km (39 mi) WNW of here earthquakes near Clackamas County

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

Aftershocks so far

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

  1. 2.1 8 km ESE of Molalla, Oregon
  2. 1.6 8 km SW of Vernonia, Oregon
  3. 1.6 5 km SSE of Molalla, Oregon
  4. 2.0 2 km SE of Amity, Oregon
  5. 1.9 1 km SE of Vancouver, Washington
  6. 1.6 7 km ESE of Molalla, Oregon
  7. 1.9 21 km W of Forest Grove, Oregon
  8. 2.0 7 km WNW of McMinnville, Oregon
  9. 1.5 5 km WNW of King City, Oregon
  10. 1.7 7 km ESE of Amity, Oregon
  11. 1.7 3 km NW of Venersborg, Washington
  12. 1.5 4 km WNW of Camas, Washington
  13. 2.0 2 km WNW of Dundee, Oregon
  14. 1.7 8 km S of Molalla, Oregon
  15. 1.9 7 km S of Dayton, 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.