QuakeIndex

explosion · reviewed by a seismologist

M 1.5ml

Earthquake near Lewisville, WA

No earthquake was likely felt in Lewisville in the 24 hours to 6:20 pm PST (02:20 UTC). The last one was M 3.0, 27 km (17 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 Lewisville

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.5 explosion was recorded 4 km (2 mi) east of Lewisville, WA, at 2:15 pm PDT on 22 March 2021 (21:15 UTC), less than 1 km deep.

USGS: 3 km E of Lewisville, Washington

33 km (20 mi) NNE of Portland, OR · 21 km (13 mi) NNE of Vancouver, WA

2:15 pm PDT, Mar 22, 2021 · · -0.8 km deep · released about 5.7 lb of TNT

10 km30 km60 km120 km N Clark County 4 kmMultnomah County 29 kmCowlitz County 47 kmSkamania County 47 kmColumbia County 49 kmWashington County 56 kmHood River County 71 kmClackamas County 75 kmLewis 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
2:15 pm PDT on 22 March 2021 ()
Where
4 km (2 mi) east of Lewisville, WA · earthquakes near Lewisville
Magnitude
M 1.5 (ml)
Depth
-0.8 km below the surface
Felt
no reports yet
Nearest
Clark County, 4 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2061 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 Lewisville, 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: Venersborg, Battle Ground, Hockinson, Meadow Glade, Yacolt, Brush Prairie.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 5.7 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 2,600,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.7 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 5 earthquakes of M5 or more within 50 km:

  1. 5.2 5 km E of Bridgeton, Oregon · 25 km SSW of this epicentre
  2. 5.2 37 km NNE of Amboy, Washington · 49 km NNE of this epicentre
  3. 5.1 28 km ENE of Amboy, Washington · 37 km NE of this epicentre
  4. 5.0 3 km SW of Portland, Oregon · 38 km SSW of this epicentre
  5. 5.0 38 km NNE of Amboy, Washington · 50 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 45.8032, -122.4747. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Clark County, WA 4 km (2 mi) SSW earthquakes near Clark County
Multnomah County, OR 29 km (18 mi) S earthquakes near Multnomah County
Cowlitz County, WA 47 km (29 mi) NNW earthquakes near Cowlitz County
Skamania County, WA 47 km (29 mi) ENE earthquakes near Skamania County
Columbia County, OR 49 km (31 mi) WNW earthquakes near Columbia County
Washington County, OR 56 km (35 mi) WSW earthquakes near Washington County

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

Aftershocks so far

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

  1. 1.5 6 km ENE of Prescott, Oregon
  2. 1.7 7 km ENE of Prescott, Oregon
  3. 1.6 3 km E of Battle Ground, Washington
  4. 1.7 3 km NNE of La Center, Washington
  5. 2.0 19 km N of Amboy, Washington
  6. 1.5 37 km NNE of Amboy, Washington
  7. 2.1 9 km ENE of Kalama, Washington
  8. 1.7 4 km ENE of Lewisville, Washington
  9. 1.6 3 km W of Yacolt, Washington
  10. 1.6 2 km WNW of Saint Helens, Oregon
  11. 2.1 1 km WNW of Deer Island, Oregon
  12. 1.7 1 km SW of Columbia City, Oregon
  13. 1.7 1 km NNE of Battle Ground, Washington
  14. 1.8 2 km E of Saint Helens, Oregon
  15. 1.5 2 km WSW of Yacolt, 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.