QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Saint Helens, OR

No earthquake was likely felt in Saint Helens in the 24 hours to 1:55 pm PST (21:55 UTC). The last one was M 3.0, 5 km (3 mi) WNW, at 7:25 am PDT on 22 October 2026, estimated intensity II (weak) in town; 113 felt reports to USGS. Every earthquake near Saint Helens

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 3 km (2 mi) east of Saint Helens, OR, at 12:16 pm PDT on 15 August 2022 (19:16 UTC), less than 1 km deep.

USGS: 2 km E of Saint Helens, Oregon

38 km (23 mi) NNW of Portland, OR · 29 km (18 mi) NNW of Vancouver, WA

12:16 pm PDT, Aug 15, 2022 · · -0.4 km deep · released about 17 lb of TNT

10 km30 km60 km120 km N Clark County 25 kmColumbia County 25 kmCowlitz County 38 kmWashington County 43 kmMultnomah County 45 kmSkamania County 66 kmWahkiakum County 69 kmClatsop County 74 kmYamhill County 80 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
12:16 pm PDT on 15 August 2022 ()
Where
3 km (2 mi) east of Saint Helens, OR · earthquakes near Saint Helens
Magnitude
M 1.8 (ml)
Depth
-0.4 km below the surface
Felt
no reports yet
Nearest
Clark County, 25 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 612 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 Saint Helens, 3 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: Columbia City, Woodland, Ridgefield, Warren, La Center, Scappoose.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 17 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 5.8 870,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 620,000× the energy of this one
  3. Around the size people start to feel M 3.0 55× the energy of this one
  4. This earthquake M 1.8 about 17 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 2 earthquakes of M5 or more within 50 km:

  1. 5.2 5 km E of Bridgeton, Oregon · 32 km SSE of this epicentre
  2. 5.0 3 km SW of Portland, Oregon · 41 km S 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 45.8637, -122.7740. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, WA 25 km (15 mi) ESE earthquakes near Clark County
Columbia County, OR 25 km (16 mi) WNW earthquakes near Columbia County
Cowlitz County, WA 38 km (23 mi) N earthquakes near Cowlitz County
Washington County, OR 43 km (27 mi) SW earthquakes near Washington County
Multnomah County, OR 45 km (28 mi) SE earthquakes near Multnomah County
Skamania County, WA 66 km (41 mi) ENE earthquakes near Skamania 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. 1.9 3 km NNE of Deer Island, Oregon
  2. 1.9 1 km ESE of La Center, Washington
  3. 1.6 5 km NNE of Kalama, Washington
  4. 3.1 4 km WSW of Deer Island, Oregon
  5. 1.6 10 km SW of Vernonia, Oregon
  6. 1.6 10 km NW of West Longview, Washington
  7. 1.7 2 km WNW of Yacolt, Washington
  8. 1.8 2 km ENE of Brush Prairie, Washington
  9. 1.8 6 km NE of Woodland, Washington
  10. 1.5 13 km SSE of Vernonia, Oregon
  11. 1.7 5 km ENE of Prescott, Oregon
  12. 1.7 3 km W of Columbia City, Oregon
  13. 1.8 4 km NNW of West Longview, Washington
  14. 1.7 Washington-Oregon border region
  15. 1.6 31 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.