QuakeIndex

explosion · reviewed by a seismologist

M 1.7ml

Earthquake near Sweet Home, OR

No earthquake was likely felt in Sweet Home in the 24 hours to 9:05 am PST (17:05 UTC). The last one was M 2.0, 4 km (3 mi) N, at 4:16 pm PDT on 2 September 2025, estimated intensity II (weak) in town. Every earthquake near Sweet Home

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.7 explosion was recorded in Sweet Home, OR, at 1:26 pm PDT on 28 August 2020 (20:26 UTC), less than 1 km deep.

USGS: 1 km NNW of Sweet Home, Oregon

37 km (23 mi) SE of Albany, OR · 126 km (78 mi) S of Portland, OR

1:26 pm PDT, Aug 28, 2020 · · -0.8 km deep · released about 9.3 lb of TNT

10 km30 km60 km120 km N Linn County 18 kmLane County 55 kmBenton County 55 kmMarion County 56 kmPolk County 76 kmClackamas County 94 kmLincoln County 97 kmYamhill County 104 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
1:26 pm PDT on 28 August 2020 ()
Where
in Sweet Home, OR · earthquakes near Sweet Home
Magnitude
M 1.7 (ml)
Depth
-0.8 km below the surface
Felt
no reports yet
Nearest
Linn County, 18 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2268 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 12 km (7 mi) from the epicentre. 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: South Lebanon, Brownsville, Lebanon.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 9.3 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,100,000× the energy of this one
  3. Around the size people start to feel M 3.0 100× the energy of this one
  4. This earthquake M 1.7 about 9.3 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 since 1900 lists no earthquake of M5 or more within 50 km.

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 44.4067, -122.7388. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Linn County, OR 18 km (11 mi) ENE earthquakes near Linn County
Lane County, OR 55 km (34 mi) SSW earthquakes near Lane County
Benton County, OR 55 km (34 mi) W earthquakes near Benton County
Marion County, OR 56 km (35 mi) NNE earthquakes near Marion County
Polk County, OR 76 km (47 mi) NW earthquakes near Polk County
Clackamas County, OR 94 km (59 mi) NNE earthquakes near Clackamas County

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

Aftershocks so far

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

  1. 2.0 5 km NNE of Sweet Home, Oregon
  2. 1.6 15 km N of Cascadia, Oregon
  3. 1.7 Oregon
  4. 2.1 Oregon
  5. 1.7 16 km SSE of Cascadia, Oregon
  6. 1.5 15 km ENE of Springfield, Oregon
  7. 2.0 3 km ENE of Millersburg, Oregon
  8. 1.6 5 km N of Waterloo, Oregon
  9. 1.7 3 km SSE of Springfield, Oregon
  10. 1.7 2 km NW of Sweet Home, Oregon
  11. 1.6 4 km E of Lebanon, Oregon
  12. 1.8 4 km WNW of Mehama, Oregon
  13. 1.8 2 km W of Mehama, Oregon
  14. 1.8 3 km W of Mehama, Oregon
  15. 2.0 3 km W of Mehama, 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.