QuakeIndex

explosion · reviewed by a seismologist

M 1.6ml

Earthquake near Shelton, WA

No earthquake was likely felt in Shelton in the 24 hours to 9:52 pm PST (05:52 UTC). The last one was M 4.2, 35 km (22 mi) NE, at 2:05 pm PDT on 29 September 2026, estimated intensity III (weak) in town; 9,329 felt reports to USGS. Every earthquake near Shelton

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.6 explosion was recorded 10 km (6 mi) south-southeast of Shelton, WA, at 11:45 am PDT on 10 October 2024 (18:45 UTC), less than 1 km deep.

USGS: 10 km SSE of Shelton, Washington

76 km (47 mi) SW of Seattle, WA · 15 km (10 mi) NW of Olympia, WA

11:45 am PDT, Oct 10, 2024 · · -0.3 km deep · released about 6.6 lb of TNT

10 km30 km60 km120 km N Mason County 26 kmThurston County 27 kmGrays Harbor County 59 kmKitsap County 65 kmPierce County 69 kmLewis County 80 kmJefferson County 83 kmPacific County 84 kmWahkiakum County 97 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
11:45 am PDT on 10 October 2024 ()
Where
10 km (6 mi) south-southeast of Shelton, WA · earthquakes near Shelton
Magnitude
M 1.6 (ml)
Depth
-0.3 km below the surface
Felt
no reports yet
Nearest
Mason County, 26 km NNW
Nearest mapped fault
Olympia structure, 2 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 763 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 Shelton, 10 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.

Likely felt in: Shelton 10 km, intensity II. Estimated for each town centre; each link is that town's own record.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 6.6 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 2,300,000× 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 6.6 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

The largest earthquake within 50 km since 2016 was M 4.1 on 2017-02-23 — about 6,200 times the energy of this one.

Before 2016, the USGS record lists 7 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 The 2001 Nisqually, Washington Earthquake · 25 km E of this epicentre
  2. 6.7 4 km WNW of Roy, Washington · 37 km ESE of this epicentre
  3. 6.1 Puget Sound region, Washington · 38 km NE of this epicentre
  4. 5.8 Puget Sound area, Washington · 21 km NE of this epicentre
  5. 5.8 8 km N of Satsop, Washington · 32 km W 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 47.1277, -123.0530. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mason County, WA 26 km (16 mi) NNW earthquakes near Mason County
Thurston County, WA 27 km (17 mi) SE earthquakes near Thurston County
Grays Harbor County, WA 59 km (36 mi) W earthquakes near Grays Harbor County
Kitsap County, WA 65 km (40 mi) NNE earthquakes near Kitsap County
Pierce County, WA 69 km (43 mi) E earthquakes near Pierce County
Lewis County, WA 80 km (50 mi) SE earthquakes near Lewis 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. 1.6 4 km SSW of Shelton, Washington
  2. 1.5 11 km S of Shelton, Washington
  3. 1.5 11 km N of Hoodsport, Washington
  4. 2.4 3 km ENE of Belfair, Washington
  5. 1.7 8 km SSW of Shelton, Washington
  6. 2.9 2 km W of Home, Washington
  7. 2.0 8 km W of Gorst, Washington
  8. 2.1 5 km S of Gorst, Washington
  9. 1.7 11 km NW of Belfair, Washington
  10. 2.3 5 km SW of Gorst, Washington
  11. 2.4 4 km SSW of Gorst, Washington
  12. 1.8 5 km WSW of Bethel, Washington
  13. 1.6 8 km SSW of Grapeview, Washington
  14. 1.6 16 km WNW of Skokomish, Washington
  15. 1.9 14 km WNW of Belfair, 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.