QuakeIndex

explosion · reviewed by a seismologist

M 1.8md

Earthquake near Yacolt, WA

No earthquake was likely felt in Yacolt in the 24 hours to 12:29 pm PST (20:29 UTC). The last one was M 1.6, 7 km (5 mi) SW, at 4:25 pm PDT on 19 October 2026, estimated intensity II (weak) in town. Every earthquake near Yacolt

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 4 km (3 mi) west-southwest of Yacolt, WA, at 3:55 pm PDT on 2 September 2026 (22:55 UTC), less than 1 km deep.

USGS: 4 km WSW of Yacolt, Washington

39 km (24 mi) NNE of Portland, OR · 27 km (17 mi) NNE of Vancouver, WA

3:55 pm PDT, Sep 2, 2026 · · -0.5 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Clark County 10 kmMultnomah County 35 kmCowlitz County 41 kmSkamania County 43 kmColumbia County 49 kmWashington County 60 kmHood River County 73 kmClackamas County 80 kmLewis County 81 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
3:55 pm PDT on 2 September 2026 ()
Where
4 km (3 mi) west-southwest of Yacolt, WA · earthquakes near Yacolt
Magnitude
M 1.8 (md)
Depth
-0.5 km below the surface
Felt
no reports yet
Nearest
Clark County, 10 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 71 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 Yacolt, 4 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: Amboy, Lewisville, Venersborg, Battle Ground, Hockinson, Meadow Glade.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 15 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 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 17 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.7 38 km NNE of Amboy, Washington · 44 km NNE of this epicentre
  2. 5.2 5 km E of Bridgeton, Oregon · 31 km SSW of this epicentre
  3. 5.2 37 km NNE of Amboy, Washington · 43 km NNE of this epicentre
  4. 5.1 28 km ENE of Amboy, Washington · 32 km NE of this epicentre
  5. 5.1 Washington · 47 km NNE 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 45.8570, -122.4583. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, WA 10 km (6 mi) SSW earthquakes near Clark County
Multnomah County, OR 35 km (21 mi) S earthquakes near Multnomah County
Cowlitz County, WA 41 km (26 mi) NNW earthquakes near Cowlitz County
Skamania County, WA 43 km (27 mi) ENE earthquakes near Skamania County
Columbia County, OR 49 km (31 mi) WNW earthquakes near Columbia County
Washington County, OR 60 km (37 mi) SW earthquakes near Washington County

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

Aftershocks so far

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

  1. 0.2 38 km NNE of Amboy, Washington
  2. 1.1 3 km NNE of Hockinson, Washington
  3. 0.1 38 km NNE of Amboy, Washington
  4. 0.0 34 km NNE of Amboy, Washington
  5. 0.3 38 km NNE of Amboy, Washington
  6. 0.3 34 km NNE of Amboy, Washington
  7. -0.1 34 km NNE of Amboy, Washington
  8. 0.3 34 km NNE of Amboy, Washington
  9. 0.1 37 km NNE of Amboy, Washington
  10. 0.7 38 km NNE of Amboy, Washington
  11. 1.1 4 km W of Yacolt, Washington
  12. 0.2 38 km NNE of Amboy, Washington
  13. 0.1 38 km NNE of Amboy, Washington
  14. 1.6 20 km E of Castle Rock, Washington
  15. 0.1 37 km NNE of Amboy, Washington

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.