QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

Earthquake near Morton, WA

No earthquake was likely felt in Morton in the 24 hours to 2:25 am PST (10:25 UTC). The last one was M 4.2, 100 km (62 mi) NNW, at 2:05 pm PDT on 29 September 2026, estimated intensity II (weak) in town; 9,329 felt reports to USGS. Every earthquake near Morton

This page: a magnitude 1.5 earthquake was recorded 23 km (14 mi) south of Morton, WA, at 12:27 pm PST on 22 December 2017 (20:27 UTC), 11 km deep.

USGS: 22 km S of Morton, Washington

96 km (59 mi) NNE of Portland, OR

12:27 pm PST, Dec 22, 2017 · · 11 km deep · released about 6.2 lb of TNT

Every earthquake near Morton Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lewis County 27 kmCowlitz County 36 kmSkamania County 43 kmClark County 67 kmColumbia County 78 kmThurston County 78 kmPierce County 78 kmWahkiakum County 90 kmMultnomah County 90 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
12:27 pm PST on 22 December 2017 ()
Where
23 km (14 mi) south of Morton, WA · earthquakes near Morton
Magnitude
M 1.5 (ml)
Depth
11 km below the surface
Felt
no reports yet
Nearest
Lewis County, 27 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 600 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 1 km (1 mi) from the epicentre. In Morton, 23 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.

How big was it?

This earthquake released about 6.2 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 1,700,000× the energy of this one
  3. Around the size people start to feel M 3.0 150× the energy of this one
  4. This earthquake M 1.5 about 6.2 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 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 5.7 38 km NNE of Amboy, Washington · 17 km SSE of this epicentre
  2. 5.2 37 km NNE of Amboy, Washington · 17 km SSE of this epicentre
  3. 5.2 23 km S of Morton, Washington · 2 km E of this epicentre
  4. 5.1 28 km ENE of Amboy, Washington · 38 km SSE of this epicentre
  5. 5.1 Washington · 16 km SSE 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 46.3525, -122.2617. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lewis County, WA 27 km (17 mi) NNW earthquakes near Lewis County
Cowlitz County, WA 36 km (23 mi) WSW earthquakes near Cowlitz County
Skamania County, WA 43 km (27 mi) SSE earthquakes near Skamania County
Clark County, WA 67 km (42 mi) SSW earthquakes near Clark County
Columbia County, OR 78 km (48 mi) SW earthquakes near Columbia County
Thurston County, WA 78 km (48 mi) NNW earthquakes near Thurston County

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

Aftershocks so far

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

  1. 1.8 23 km SSE of Mossyrock, Washington
  2. 1.8 23 km SSE of Mossyrock, Washington
  3. 1.8 12 km NNW of Amboy, Washington
  4. 1.6 Washington
  5. 1.6 20 km NE of Kalama, Washington
  6. 1.7 8 km S of Morton, Washington
  7. 2.1 Washington
  8. 1.7 23 km NNE of Amboy, Washington
  9. 1.8 18 km ESE of Castle Rock, Washington
  10. 1.8 12 km SE of Mossyrock, Washington
  11. 1.5 25 km S of Mossyrock, Washington
  12. 1.7 9 km SE of Mossyrock, Washington
  13. 1.9 13 km NNE of Mossyrock, Washington
  14. 1.5 6 km SE of Mossyrock, Washington
  15. 1.9 37 km SSE of Morton, 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.