QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Morton, WA

Yes. A magnitude 1.6 earthquake was recorded 40 km (25 mi) E of Morton, WA, at 9:22 am PST on 15 December 2017 (17:22 UTC), less than 1 km deep.

This was on 15 December 2017. The latest near Morton: M 2.5 on 16 March 2026.

USGS: 9 km SW of Packwood, Washington

9:22 am PST, Dec 15, 2017 · · -0.4 km deep · released about 7.6 lb of TNT

Every earthquake near Morton Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lewis County 48 kmSkamania County 59 kmPierce County 65 kmYakima County 78 kmCowlitz County 81 kmThurston County 93 kmClark County 102 kmKittitas County 105 kmKlickitat County 105 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
9:22 am PST on 15 December 2017 ()
Where
40 km (25 mi) E of Morton, WA · earthquakes near Morton
Magnitude
M 1.6 (ml)
Depth
-0.4 km below the surface
Felt
no reports yet
Nearest
Lewis County, 48 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3224 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 11 km (7 mi) from the epicentre. In Morton, 40 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.

How big was it?

This earthquake released about 7.6 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.6 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,400,000× the energy of this one
  3. Around the size people start to feel M 3.0 130× the energy of this one
  4. This earthquake M 1.6 about 7.6 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 · 50 km SW of this epicentre
  2. 5.2 23 km S of Morton, Washington · 43 km WSW of this epicentre
  3. 5.1 Washington · 47 km SW of this epicentre
  4. 5.1 38 km NNE of Amboy, Washington · 49 km SW of this epicentre
  5. 5.1 38 km S of Morton, Washington · 49 km SW 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 46.5373, -121.7513. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lewis County, WA 48 km (30 mi) W earthquakes near Lewis County
Skamania County, WA 59 km (37 mi) SSW earthquakes near Skamania County
Pierce County, WA 65 km (40 mi) NNW earthquakes near Pierce County
Yakima County, WA 78 km (48 mi) E earthquakes near Yakima County
Cowlitz County, WA 81 km (50 mi) WSW earthquakes near Cowlitz County
Thurston County, WA 93 km (58 mi) WNW earthquakes near Thurston County

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

Aftershocks so far

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

  1. 1.5 23 km ENE of Ashford, Washington
  2. 1.7 9 km NE of Ashford, Washington
  3. 1.5 23 km ENE of Ashford, Washington
  4. 1.7 23 km ENE of Ashford, Washington
  5. 1.6 23 km ENE of Ashford, Washington
  6. 1.6 21 km ESE of Packwood, Washington
  7. 1.5 22 km ENE of Ashford, Washington
  8. 2.3 15 km S of Packwood, Washington
  9. 1.9 37 km SSE of Morton, Washington
  10. 1.6 15 km NE of Ashford, Washington
  11. 1.6 23 km ENE of Ashford, Washington
  12. 1.7 5 km ENE of Ashford, Washington
  13. 1.7 30 km SSW of Packwood, Washington
  14. 1.6 4 km SE of Ashford, Washington
  15. 1.6 22 km ENE of Ashford, 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.