QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

9 km SSW of Seabeck, Washington

· 24 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Kitsap County 18 kmMason County 33 kmJefferson County 57 kmIsland County 68 kmThurston County 69 kmPierce County 77 kmKing County 77 kmGrays Harbor County 88 kmClallam County 99 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
Magnitude
M 1.8 (ml)
Depth
24 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
Kitsap County, 18 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 493 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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.

Where

Epicentre 47.5560, -122.8600. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Kitsap County, WA 18 km (11 mi) WSW of here earthquakes near Kitsap County
Mason County, WA 33 km (20 mi) NE of here earthquakes near Mason County
Jefferson County, WA 57 km (36 mi) ESE of here earthquakes near Jefferson County
Island County, WA 68 km (43 mi) SSW of here earthquakes near Island County
Thurston County, WA 69 km (43 mi) N of here earthquakes near Thurston County
Pierce County, WA 77 km (48 mi) NW of here earthquakes near Pierce County

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

Aftershocks so far

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

  1. 1.6 3 km W of Quilcene, Washington
  2. 1.5 5 km WSW of Erlands Point-Kitsap Lake, Washington
  3. 1.5 0 km ESE of Browns Point, Washington
  4. 2.1 5 km S of Gorst, Washington
  5. 1.7 11 km NW of Belfair, Washington
  6. 1.6 2 km E of Enetai, Washington
  7. 2.6 1 km ENE of Enetai, Washington
  8. 1.6 2 km SW of Port Ludlow, Washington
  9. 2.3 5 km SW of Gorst, Washington
  10. 2.4 4 km SSW of Gorst, Washington
  11. 1.8 5 km WSW of Bethel, Washington
  12. 1.6 8 km SSW of Grapeview, Washington
  13. 1.6 16 km WNW of Skokomish, Washington
  14. 1.9 14 km WNW of Belfair, Washington
  15. 1.9 6 km SSE of Port Ludlow, 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.1 on 2017-02-23 — it released about 3,100 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.