QuakeIndex

Earthquake · reviewed by a seismologist

M 1.6ml

Earthquake near Graham, WA

No earthquake was likely felt in Graham in the 24 hours to 5:53 am PST (13:53 UTC). The last one was M 1.6, 5 km (3 mi) SE, at 11:47 am PST on 9 November 2026, estimated intensity II (weak) in town. Every earthquake near Graham

This page: a magnitude 1.6 earthquake was recorded 46 km (29 mi) east-southeast of Graham, WA, at 4:50 pm PDT on 16 May 2023 (23:50 UTC), 1.1 km deep.

USGS: Washington

96 km (60 mi) SSE of Seattle, WA

4:50 pm PDT, May 16, 2023 · · 1.1 km deep · released about 6.8 lb of TNT

10 km30 km60 km120 km N Pierce County 37 kmLewis County 56 kmKing County 71 kmThurston County 82 kmKittitas County 88 kmYakima County 89 kmSkamania County 93 kmCowlitz County 101 kmKitsap County 110 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
4:50 pm PDT on 16 May 2023 ()
Where
46 km (29 mi) east-southeast of Graham, WA · earthquakes near Graham
Magnitude
M 1.6 (ml)
Depth
1.1 km below the surface
Felt
no reports yet
Nearest
Pierce County, 37 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1274 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 Graham, 46 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 6.8 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 2,200,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,600,000× the energy of this one
  3. Around the size people start to feel M 3.0 140× the energy of this one
  4. This earthquake M 1.6 about 6.8 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 · 46 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 46.8510, -121.7607. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Pierce County, WA 37 km (23 mi) NW earthquakes near Pierce County
Lewis County, WA 56 km (35 mi) WSW earthquakes near Lewis County
King County, WA 71 km (44 mi) N earthquakes near King County
Thurston County, WA 82 km (51 mi) W earthquakes near Thurston County
Kittitas County, WA 88 km (54 mi) ENE earthquakes near Kittitas County
Yakima County, WA 89 km (56 mi) ESE earthquakes near Yakima County

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

Aftershocks so far

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

  1. 2.2 13 km NNE of Ashford, Washington
  2. 1.5 1 km SSE of Kapowsin, Washington
  3. 1.9 5 km E of Enumclaw, Washington
  4. 1.6 1 km WNW of Kapowsin, Washington
  5. 1.6 24 km NNE of Packwood, Washington
  6. 1.5 2 km ESE of Buckley, Washington
  7. 1.7 0 km WSW of Kapowsin, Washington
  8. 1.7 12 km E of Wilkeson, Washington
  9. 1.6 1 km SE of Kapowsin, Washington
  10. 1.5 15 km NNE of Ashford, Washington
  11. 1.5 19 km SSE of Carbonado, Washington
  12. 1.8 17 km SE of Carbonado, Washington
  13. 2.3 15 km NNE of Ashford, Washington
  14. 2.0 3 km ENE of Eatonville, Washington
  15. 1.9 10 km NE 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.