QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Kelso, WA

No earthquake was likely felt in Kelso in the 24 hours to 10:26 am PST (18:26 UTC). The last one was M 3.0, 29 km (18 mi) S, at 7:25 am PDT on 22 October 2026, estimated intensity II (weak) in town; 113 felt reports to USGS. Every earthquake near Kelso

This page: a magnitude 1.8 earthquake was recorded 49 km (31 mi) northeast of Kelso, WA, at 2:50 am PDT on 29 June 2023 (09:50 UTC), 13 km deep.

USGS: 10 km SSE of Mossyrock, Washington

2:50 am PDT, Jun 29, 2023 · · 13 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Lewis County 16 kmCowlitz County 33 kmSkamania County 59 kmThurston County 63 kmPierce County 71 kmClark County 75 kmColumbia County 75 kmWahkiakum County 78 kmMultnomah 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
2:50 am PDT on 29 June 2023 ()
Where
49 km (31 mi) northeast of Kelso, WA · earthquakes near Kelso
Magnitude
M 1.8 (ml)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Lewis County, 16 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 625 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Kelso, 49 km away, the estimate is intensity I (not felt). 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: Morton.

How big was it?

This earthquake released about 13 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 1,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 840,000× the energy of this one
  3. Around the size people start to feel M 3.0 75× the energy of this one
  4. This earthquake M 1.8 about 13 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 15 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.7 38 km NNE of Amboy, Washington · 32 km SE of this epicentre
  2. 5.2 37 km NNE of Amboy, Washington · 32 km SE of this epicentre
  3. 5.2 23 km S of Morton, Washington · 18 km SE of this epicentre
  4. 5.1 Washington · 31 km SE of this epicentre
  5. 5.1 38 km NNE of Amboy, Washington · 32 km SE 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 46.4410, -122.4293. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lewis County, WA 16 km (10 mi) NNE earthquakes near Lewis County
Cowlitz County, WA 33 km (21 mi) SW earthquakes near Cowlitz County
Skamania County, WA 59 km (37 mi) SE earthquakes near Skamania County
Thurston County, WA 63 km (39 mi) NNW earthquakes near Thurston County
Pierce County, WA 71 km (44 mi) NNE earthquakes near Pierce County
Clark County, WA 75 km (46 mi) S earthquakes near Clark County

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

Aftershocks so far

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

  1. 1.7 24 km N of Amboy, Washington
  2. 1.5 5 km WSW of Napavine, Washington
  3. 2.0 38 km NNE of Amboy, Washington
  4. 2.2 5 km SW of Napavine, Washington
  5. 1.6 6 km ENE of Mossyrock, Washington
  6. 1.8 7 km SSE of McKenna, Washington
  7. 1.8 10 km NE of Castle Rock, Washington
  8. 1.6 2 km N of Onalaska, Washington
  9. 2.9 3 km N of Onalaska, Washington
  10. 1.8 4 km NW of Winlock, Washington
  11. 1.6 27 km S of Morton, Washington
  12. 2.5 27 km S of Morton, Washington
  13. 2.4 14 km SW of Alder, Washington
  14. 1.6 5 km WSW of La Grande, Washington
  15. 1.6 34 km NE 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.