QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Graham, WA

Yes. A magnitude 1.6 earthquake was recorded 49 km (30 mi) ESE of Graham, WA, at 3:17 am PDT on 12 September 2017 (10:17 UTC), less than 1 km deep.

This was on 12 September 2017. The latest near Graham: M 2.5 on 16 March 2026.

USGS: Washington

98 km (61 mi) SSE of Seattle, WA

3:17 am PDT, Sep 12, 2017 · · -2.2 km deep · released about 8.7 lb of TNT

Every earthquake near Graham Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Pierce County 40 kmLewis County 57 kmKing County 73 kmThurston County 84 kmKittitas County 86 kmYakima County 87 kmSkamania County 92 kmCowlitz County 102 kmKitsap County 113 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
3:17 am PDT on 12 September 2017 ()
Where
49 km (30 mi) ESE of Graham, WA · earthquakes near Graham
Magnitude
M 1.6 (ml)
Depth
-2.2 km below the surface
Felt
no reports yet
Nearest
Pierce County, 40 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3318 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 Graham, 49 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 8.7 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 1,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,200,000× the energy of this one
  3. Around the size people start to feel M 3.0 110× the energy of this one
  4. This earthquake M 1.6 about 8.7 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 one earthquake of M5 or more within 50 km:

  1. 5.0 23 km ESE of Packwood, Washington · 44 km SE 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 46.8417, -121.7288. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pierce County, WA 40 km (25 mi) NW earthquakes near Pierce County
Lewis County, WA 57 km (36 mi) WSW earthquakes near Lewis County
King County, WA 73 km (45 mi) N earthquakes near King County
Thurston County, WA 84 km (52 mi) W earthquakes near Thurston County
Kittitas County, WA 86 km (53 mi) ENE earthquakes near Kittitas County
Yakima County, WA 87 km (54 mi) ESE earthquakes near Yakima County

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

Aftershocks so far

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

  1. 1.5 2 km ENE of Kapowsin, Washington
  2. 1.5 14 km SSE of Carbonado, Washington
  3. 1.6 19 km E of Morton, Washington
  4. 1.8 11 km N of Packwood, Washington
  5. 1.8 20 km ESE of Packwood, Washington
  6. 1.9 20 km ESE of Packwood, Washington
  7. 1.6 20 km ESE of Packwood, Washington
  8. 1.6 10 km W of Greenwater, Washington
  9. 1.6 11 km W of Greenwater, Washington
  10. 1.6 3 km ENE of Kapowsin, Washington
  11. 1.8 20 km ESE of Packwood, Washington
  12. 1.6 20 km ESE of Packwood, Washington
  13. 2.5 20 km ESE of Packwood, Washington
  14. 1.6 12 km W of Greenwater, Washington
  15. 2.0 13 km NNE 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.