QuakeIndex

explosion · reviewed by a seismologist

M 1.9md

Earthquake near Yamhill, OR

No earthquake was likely felt in Yamhill in the 24 hours to 7:06 am PST (15:06 UTC). The last one was M 2.0, 13 km (8 mi) ESE, at 2:30 pm PDT on 1 June 2026, estimated intensity II (weak) in town. Every earthquake near Yamhill

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.9 explosion was recorded 24 km (15 mi) west of Yamhill, OR, at 10:10 am PDT on 16 August 2018 (17:10 UTC), less than 1 km deep.

USGS: 23 km W of Yamhill, Oregon

69 km (43 mi) WSW of Portland, OR · 48 km (30 mi) WSW of Hillsboro, OR

10:10 am PDT, Aug 16, 2018 · · -0.5 km deep · released about 23 lb of TNT

10 km30 km60 km120 km N Yamhill County 17 kmTillamook County 24 kmWashington County 39 kmPolk County 50 kmColumbia County 74 kmClatsop County 78 kmLincoln County 85 kmMultnomah County 87 kmMarion County 87 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
10:10 am PDT on 16 August 2018 ()
Where
24 km (15 mi) west of Yamhill, OR · earthquakes near Yamhill
Magnitude
M 1.9 (md)
Depth
-0.5 km below the surface
Felt
no reports yet
Nearest
Yamhill County, 17 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3007 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 15 km (9 mi) from the epicentre. In Yamhill, 24 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: Carlton, McMinnville, Sheridan, Willamina.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 23 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 660,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 470,000× the energy of this one
  3. Around the size people start to feel M 3.0 42× the energy of this one
  4. This earthquake M 1.9 about 23 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 45.3432, -123.4903. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Yamhill County, OR 17 km (11 mi) SE earthquakes near Yamhill County
Tillamook County, OR 24 km (15 mi) WNW earthquakes near Tillamook County
Washington County, OR 39 km (24 mi) NE earthquakes near Washington County
Polk County, OR 50 km (31 mi) S earthquakes near Polk County
Columbia County, OR 74 km (46 mi) NNE earthquakes near Columbia County
Clatsop County, OR 78 km (48 mi) NNW earthquakes near Clatsop 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. 1.5 3 km ESE of Rose Lodge, Oregon
  2. 1.9 19 km WSW of Vernonia, Oregon
  3. 2.0 3 km WSW of Oceanside, Oregon
  4. 1.7 5 km SSW of Saint Paul, Oregon
  5. 1.5 2 km ESE of Rose Lodge, Oregon
  6. 1.6 12 km ESE of Hebo, Oregon
  7. 1.6 3 km S of Fort Hill Census Designated Place, Oregon
  8. 1.8 3 km W of Saint Paul, Oregon
  9. 2.5 1 km S of Tillamook, Oregon
  10. 1.9 Oregon
  11. 1.7 8 km SE of Amity, Oregon
  12. 2.0 4 km WNW of Dundee, Oregon
  13. 1.6 3 km ESE of Rose Lodge, Oregon
  14. 2.1 3 km ESE of Rose Lodge, Oregon
  15. 1.6 11 km NNW of Sheridan, 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.