QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Molalla, OR

No earthquake was likely felt in Molalla in the 24 hours to 3:49 pm PST (23:49 UTC). The last one was M 2.1, 8 km (5 mi) ESE, at 12:47 pm PDT on 1 September 2026, estimated intensity II (weak) in town. Every earthquake near Molalla

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 6 km (4 mi) east-southeast of Molalla, OR, at 3:15 pm PDT on 21 October 2025 (22:15 UTC), less than 1 km deep.

USGS: 6 km ESE of Molalla, Oregon

48 km (30 mi) SSE of Portland, OR · 40 km (25 mi) SSE of Tigard, OR

3:15 pm PDT, Oct 21, 2025 · · -0.5 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Clackamas County 25 kmMarion County 25 kmMultnomah County 48 kmYamhill County 65 kmWashington County 67 kmLinn County 70 kmClark County 73 kmPolk County 74 kmHood River County 79 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
3:15 pm PDT on 21 October 2025 ()
Where
6 km (4 mi) east-southeast of Molalla, OR · earthquakes near Molalla
Magnitude
M 1.8 (ml)
Depth
-0.5 km below the surface
Felt
no reports yet
Nearest
Clackamas County, 25 km E
Nearest mapped fault
Mount Angel fault, 19 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 387 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 14 km (9 mi) from the epicentre. In Molalla, 6 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: Mulino, Beavercreek, Canby, Estacada, Mount Angel, Hubbard.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 lists 2 earthquakes of M5 or more within 50 km:

  1. 5.6 4 km E of Scotts Mills, Oregon · 12 km SW of this epicentre
  2. 5.0 3 km SW of Portland, Oregon · 45 km NNW of this epicentre

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 45.1195, -122.5043. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clackamas County, OR 25 km (15 mi) E earthquakes near Clackamas County
Marion County, OR 25 km (16 mi) SSW earthquakes near Marion County
Multnomah County, OR 48 km (30 mi) N earthquakes near Multnomah County
Yamhill County, OR 65 km (41 mi) WNW earthquakes near Yamhill County
Washington County, OR 67 km (42 mi) NW earthquakes near Washington County
Linn County, OR 70 km (44 mi) S earthquakes near Linn 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. 1.3 3 km SSW of Tualatin, Oregon
  2. 1.6 3 km SSW of Scotts Mills, Oregon
  3. 1.4 6 km SE of Molalla, Oregon
  4. 0.9 6 km WNW of King City, Oregon
  5. 1.5 7 km NW of Mount Hood Village, Oregon
  6. 1.6 1 km SW of Mount Angel, Oregon
  7. 1.2 13 km SE of Scotts Mills, Oregon
  8. 2.1 8 km ESE of Molalla, Oregon
  9. 1.6 5 km SSE of Molalla, Oregon
  10. 1.5 9 km ESE of Scotts Mills, Oregon
  11. 1.6 7 km ESE of Molalla, Oregon
  12. 1.7 4 km NNW of Mount Hood Village, Oregon
  13. 1.5 5 km WNW of King City, Oregon
  14. 2.0 2 km WNW of Dundee, Oregon
  15. 2.1 10 km NNE of Sandy, 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.