QuakeIndex

explosion · reviewed by a seismologist

M 1.6ml

Earthquake near Mill City, OR

USGS: 9 km N of Mill City, Oregon

79 km (49 mi) S of Portland, OR · 44 km (27 mi) ESE of Salem, OR

10:06 am PDT, Jun 1, 2018 · · -0.5 km deep · released about 7.1 lb of TNT

10 km30 km60 km120 km N Marion County 11 kmLinn County 39 kmClackamas County 42 kmPolk County 73 kmMultnomah County 79 kmYamhill County 80 kmBenton County 84 kmWashington County 93 kmHood River County 99 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
10:06 am PDT on 1 June 2018 ()
Where
9 km (6 mi) N of Mill City, OR · earthquakes near Mill City
Magnitude
M 1.6 (ml)
Depth
-0.5 km below the surface
Felt
no reports yet
Nearest
Marion County, 11 km NW
Nearest mapped fault
Mount Angel fault, 24 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 3046 days ago

A magnitude 1.6 earthquake was recorded 9 km (6 mi) N of Mill City, OR, at 10:06 am PDT on 1 June 2018 (17:06 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Lyons, Sublimity, Stayton.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 7.1 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,500,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.1 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 one earthquake of M5 or more within 50 km:

  1. 5.6 4 km E of Scotts Mills, Oregon · 24 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 44.8387, -122.4745. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Marion County, OR 11 km (7 mi) NW earthquakes near Marion County
Linn County, OR 39 km (24 mi) S earthquakes near Linn County
Clackamas County, OR 42 km (26 mi) NNE earthquakes near Clackamas County
Polk County, OR 73 km (45 mi) W earthquakes near Polk County
Multnomah County, OR 79 km (49 mi) N earthquakes near Multnomah County
Yamhill County, OR 80 km (50 mi) NW earthquakes near Yamhill County

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

Aftershocks so far

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

  1. 1.6 13 km ESE of Lacomb, Oregon
  2. 1.8 10 km N of Mill City, Oregon
  3. 1.7 3 km SW of Scotts Mills, Oregon
  4. 1.7 7 km SE of Crabtree, Oregon
  5. 1.6 21 km ESE of Molalla, Oregon
  6. 2.0 7 km ESE of Molalla, Oregon
  7. 1.6 4 km NNW of Waterloo, Oregon
  8. 1.8 5 km E of Crabtree, Oregon
  9. 1.8 5 km E of Silverton, Oregon
  10. 2.0 4 km E of Scotts Mills, Oregon
  11. 1.7 4 km N of Sweet Home, Oregon
  12. 2.2 3 km W of Mehama, Oregon
  13. 1.8 Washington-Oregon border region
  14. 1.6 7 km E of Molalla, Oregon
  15. 1.9 5 km SE of Silverton, 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.