QuakeIndex

Earthquake · reviewed by a seismologist

M 1.9ml

Earthquake near South Hill, WA

Yes. A magnitude 1.9 earthquake was recorded 34 km (21 mi) SSE of South Hill, WA, at 6:41 am PDT on 16 September 2017 (13:41 UTC), 6.7 km deep.

This was on 16 September 2017. The latest near South Hill: M 2.5 on 24 October 2025.

USGS: 13 km N of Ashford, Washington

86 km (53 mi) SSE of Seattle, WA · 49 km (30 mi) SE of Lakewood, WA

6:41 am PDT, Sep 16, 2017 · · 6.7 km deep · released about 18 lb of TNT

10 km30 km60 km120 km N Pierce County 21 kmLewis County 42 kmThurston County 60 kmKing County 70 kmCowlitz County 90 kmSkamania County 95 kmKitsap County 96 kmMason County 100 kmKittitas County 107 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
6:41 am PDT on 16 September 2017 ()
Where
34 km (21 mi) SSE of South Hill, WA · earthquakes near South Hill
Magnitude
M 1.9 (ml)
Depth
6.7 km below the surface
Felt
no reports yet
Nearest
Pierce County, 21 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3314 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 12 km (7 mi) from the epicentre. In South Hill, 34 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: Eatonville, Crocker, Graham, Orting.

How big was it?

This earthquake released about 18 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 840,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 600,000× the energy of this one
  3. Around the size people start to feel M 3.0 53× the energy of this one
  4. This earthquake M 1.9 about 18 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 one earthquake of M5 or more within 50 km:

  1. 6.7 4 km WNW of Roy, Washington · 45 km WNW 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 46.8768, -122.0445. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pierce County, WA 21 km (13 mi) NNW earthquakes near Pierce County
Lewis County, WA 42 km (26 mi) SW earthquakes near Lewis County
Thurston County, WA 60 km (37 mi) W earthquakes near Thurston County
King County, WA 70 km (44 mi) NNE earthquakes near King County
Cowlitz County, WA 90 km (56 mi) SSW earthquakes near Cowlitz County
Skamania County, WA 95 km (59 mi) S earthquakes near Skamania County

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

Aftershocks so far

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

  1. 1.7 11 km ESE of Enumclaw, Washington
  2. 2.0 11 km ENE of Enumclaw, Washington
  3. 1.6 4 km SE of Ashford, Washington
  4. 1.8 3 km SW of Kapowsin, Washington
  5. 1.6 22 km ENE of Ashford, Washington
  6. 1.5 2 km ENE of Kapowsin, Washington
  7. 1.5 14 km SSE of Carbonado, Washington
  8. 1.6 19 km E of Morton, Washington
  9. 1.8 11 km N of Packwood, Washington
  10. 1.6 10 km W of Greenwater, Washington
  11. 1.6 11 km W of Greenwater, Washington
  12. 1.6 3 km ENE of Kapowsin, Washington
  13. 1.6 12 km W of Greenwater, Washington
  14. 2.0 13 km NNE of Ashford, Washington
  15. 1.6 1 km SE of Kapowsin, 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.