QuakeIndex

explosion · reviewed by a seismologist

M 1.5ml

Earthquake near Mulino, OR

No earthquake was likely felt in Mulino in the 24 hours to 7:47 pm PST (03:47 UTC). The last one was M 2.1, 14 km (9 mi) SSE, at 12:47 pm PDT on 1 September 2026, estimated intensity II (weak) in town. Every earthquake near Mulino

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.5 explosion was recorded 5 km (3 mi) west of Mulino, OR, at 11:40 am PST on 21 February 2020 (19:40 UTC), less than 1 km deep.

USGS: 4 km W of Mulino, Oregon

34 km (21 mi) S of Portland, OR · 24 km (15 mi) SSE of Tigard, OR

11:40 am PST, Feb 21, 2020 · · -0.1 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N Clackamas County 36 kmMarion County 37 kmMultnomah County 40 kmWashington County 51 kmYamhill County 53 kmClark County 62 kmPolk County 70 kmLinn County 83 kmHood River County 83 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
11:40 am PST on 21 February 2020 ()
Where
5 km (3 mi) west of Mulino, OR · earthquakes near Mulino
Magnitude
M 1.5 (ml)
Depth
-0.1 km below the surface
Felt
no reports yet
Nearest
Clackamas County, 36 km ESE
Nearest mapped fault
Mount Angel fault, 21 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 2456 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 10 km (6 mi) from the epicentre. In Mulino, 5 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: Canby, Molalla, Beavercreek, Wilsonville, Hubbard, Oregon City.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 5.7 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 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 3 earthquakes of M5 or more within 50 km:

  1. 5.6 4 km E of Scotts Mills, Oregon · 22 km S of this epicentre
  2. 5.2 5 km E of Bridgeton, Oregon · 42 km N of this epicentre
  3. 5.0 3 km SW of Portland, Oregon · 31 km N 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 45.2287, -122.6422. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clackamas County, OR 36 km (22 mi) ESE earthquakes near Clackamas County
Marion County, OR 37 km (23 mi) S earthquakes near Marion County
Multnomah County, OR 40 km (25 mi) NNE earthquakes near Multnomah County
Washington County, OR 51 km (31 mi) NW earthquakes near Washington County
Yamhill County, OR 53 km (33 mi) W earthquakes near Yamhill County
Clark County, WA 62 km (38 mi) NNE earthquakes near Clark County

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

Aftershocks so far

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

  1. 1.8 3 km W of Saint Paul, Oregon
  2. 1.6 14 km ESE of Scotts Mills, Oregon
  3. 1.7 8 km SE of Amity, Oregon
  4. 2.0 4 km WNW of Dundee, Oregon
  5. 2.8 6 km SW of Aloha, Oregon
  6. 1.6 1 km SSE of King City, Oregon
  7. 2.0 4 km SE of Mill Plain, Washington
  8. 1.6 8 km ESE of Molalla, Oregon
  9. 2.6 3 km SE of Mill Plain, Washington
  10. 1.7 4 km WNW of Molalla, Oregon
  11. 2.7 4 km WNW of Molalla, Oregon
  12. 2.2 1 km SW of Carlton, Oregon
  13. 1.7 3 km SSW of Scotts Mills, Oregon
  14. 1.7 8 km SE of Molalla, Oregon
  15. 2.0 6 km NE of Amity, 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.