QuakeIndex

explosion · reviewed by a seismologist

M 1.8ml

Earthquake near Port Hadlock-Irondale, WA

No earthquake was likely felt in Port Hadlock-Irondale in the 24 hours to 1:34 pm PST (21:34 UTC). The last one was M 4.2, 70 km (44 mi) S, at 2:05 pm PDT on 29 September 2026, estimated intensity II (weak) in town; 9,329 felt reports to USGS. Every earthquake near Port Hadlock-Irondale

No: USGS classifies this as a explosion, not an earthquake. A magnitude 1.8 explosion was recorded 10 km (6 mi) west-southwest of Port Hadlock-Irondale, WA, at 12:44 pm PDT on 28 March 2022 (19:44 UTC), less than 1 km deep.

USGS: 7 km ESE of Blyn, Washington

60 km (37 mi) NW of Seattle, WA · 50 km (31 mi) WNW of Shoreline, WA

12:44 pm PDT, Mar 28, 2022 · · -0.1 km deep · released about 14 lb of TNT

10 km30 km60 km120 km N Island County 25 kmKitsap County 45 kmJefferson County 51 kmSan Juan County 58 kmClallam County 74 kmMason County 75 kmSnohomish County 86 kmSkagit County 98 kmKing 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
12:44 pm PDT on 28 March 2022 ()
Where
10 km (6 mi) west-southwest of Port Hadlock-Irondale, WA · earthquakes near Port Hadlock-Irondale
Magnitude
M 1.8 (ml)
Depth
-0.1 km below the surface
Felt
no reports yet
Nearest
Island County, 25 km NE
Nearest mapped fault
Southern Whidbey Island fault, 19 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 1690 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 13 km (8 mi) from the epicentre. In Port Hadlock-Irondale, 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.

Earthquakes near other towns within 30 km: Sequim, Port Townsend, Port Ludlow, Hansville, Lofall, Freeland.

USGS catalogues this as explosion, not an earthquake.

How big was it?

This earthquake released about 14 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 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 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. 5.3 Eastern Olympic Peninsula, Washington · 24 km SSW 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 48.0040, -122.9125. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Island County, WA 25 km (15 mi) NE earthquakes near Island County
Kitsap County, WA 45 km (28 mi) SSE earthquakes near Kitsap County
Jefferson County, WA 51 km (32 mi) WSW earthquakes near Jefferson County
San Juan County, WA 58 km (36 mi) NNW earthquakes near San Juan County
Clallam County, WA 74 km (46 mi) W earthquakes near Clallam County
Mason County, WA 75 km (47 mi) SSW earthquakes near Mason County

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

Aftershocks so far

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

  1. 1.7 1 km NNW of River Road, Washington
  2. 2.3 6 km WSW of Shoreline, Washington
  3. 1.6 4 km W of Bainbridge Island, Washington
  4. 2.0 13 km W of Ault Field, Washington
  5. 1.6 3 km SSE of Quilcene, Washington
  6. 1.5 5 km SW of Port Ludlow, Washington
  7. 1.9 2 km SSW of Esperance, Washington
  8. 1.8 1 km W of Suquamish, Washington
  9. 2.1 3 km SSE of Quilcene, Washington
  10. 1.7 4 km SE of Quilcene, Washington
  11. 1.5 4 km SW of Port Ludlow, Washington
  12. 1.6 4 km ESE of Quilcene, Washington
  13. 2.3 16 km SSE of Friday Harbor, Washington
  14. 1.7 5 km SSE of Quilcene, Washington
  15. 1.5 6 km WSW 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.

On USGS

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