QuakeIndex

explosion · reviewed by a seismologist

M 1.5ml

Earthquake near Amboy, WA

No earthquake was likely felt in Amboy in the 24 hours to 3:57 pm PST (23:57 UTC). The last one was M 1.6, 11 km (7 mi) S, at 4:25 pm PDT on 19 October 2026, estimated intensity II (weak) in town. Every earthquake near Amboy

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.5 explosion was recorded 9 km (5 mi) north of Amboy, WA, at 12:30 pm PDT on 22 May 2023 (19:30 UTC), less than 1 km deep.

USGS: 8 km N of Amboy, Washington

53 km (33 mi) NNE of Portland, OR · 41 km (25 mi) NNE of Vancouver, WA

12:30 pm PDT, May 22, 2023 · · -1.1 km deep · released about 5.9 lb of TNT

10 km30 km60 km120 km N Clark County 24 kmCowlitz County 30 kmSkamania County 38 kmMultnomah County 49 kmColumbia County 50 kmLewis County 66 kmWashington County 70 kmHood River County 80 kmWahkiakum County 83 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
12:30 pm PDT on 22 May 2023 ()
Where
9 km (5 mi) north of Amboy, WA · earthquakes near Amboy
Magnitude
M 1.5 (ml)
Depth
-1.1 km below the surface
Felt
no reports yet
Nearest
Clark County, 24 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 668 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 10 km (6 mi) from the epicentre. In Amboy, 9 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: Yacolt, Lewisville, La Center, Venersborg, Battle Ground, Woodland.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 5.9 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,800,000× the energy of this one
  3. Around the size people start to feel M 3.0 160× the energy of this one
  4. This earthquake M 1.5 about 5.9 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 · 31 km NE of this epicentre
  2. 5.2 5 km E of Bridgeton, Oregon · 45 km SSW of this epicentre
  3. 5.2 37 km NNE of Amboy, Washington · 30 km NE of this epicentre
  4. 5.2 23 km S of Morton, Washington · 43 km NNE of this epicentre
  5. 5.1 28 km ENE of Amboy, Washington · 25 km E 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 45.9868, -122.4375. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, WA 24 km (15 mi) S earthquakes near Clark County
Cowlitz County, WA 30 km (19 mi) NW earthquakes near Cowlitz County
Skamania County, WA 38 km (23 mi) E earthquakes near Skamania County
Multnomah County, OR 49 km (30 mi) S earthquakes near Multnomah County
Columbia County, OR 50 km (31 mi) W earthquakes near Columbia County
Lewis County, WA 66 km (41 mi) N earthquakes near Lewis 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. 1.5 20 km SSW of Morton, Washington
  2. 2.0 8 km WNW of Warren, Oregon
  3. 1.7 10 km SSE of Toledo, Washington
  4. 1.8 37 km NNE of Amboy, Washington
  5. 1.5 28 km SSE of Mossyrock, Washington
  6. 2.0 1 km N of Longview, Washington
  7. 3.5 20 km S of Morton, Washington
  8. 2.1 20 km SSE of Mossyrock, Washington
  9. 1.8 3 km WSW of Felida, Washington
  10. 1.7 7 km E of Kalama, Washington
  11. 1.7 24 km N of Amboy, Washington
  12. 1.7 24 km N of Amboy, Washington
  13. 2.1 2 km ENE of Ridgefield, Washington
  14. 2.0 38 km NNE of Amboy, Washington
  15. 1.5 3 km ESE of La Center, 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.