Earthquake · reviewed by a seismologist
M 1.7ml
Earthquake near Port Townsend, WA
No earthquake was likely felt in Port Townsend in the 24 hours to 5:44 pm PST (01:44 UTC). The last one was M 4.2, 80 km (50 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 Townsend
This page: a magnitude 1.7 earthquake was recorded 13 km (8 mi) west-northwest of Port Townsend, WA, at 5:02 am PDT on 28 August 2021 (12:02 UTC), 52 km deep.
USGS: 12 km ENE of Jamestown, Washington
74 km (46 mi) NW of Seattle, WA · 58 km (36 mi) W of Marysville, WA
- When
- 5:02 am PDT on 28 August 2021 ()
- Where
- 13 km (8 mi) west-northwest of Port Townsend, WA · earthquakes near Port Townsend
- Magnitude
- M 1.7 (ml)
- Depth
- 52 km below the surface
- Felt
- no reports yet
- Nearest
- Island County, 19 km E
- Nearest mapped fault
- Southern Whidbey Island fault, 5 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 614 days ago
Earthquake alerts for Port Townsend, WA
Get a notification in this browser when USGS records an earthquake near Port Townsend, WA. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.
At this magnitude and depth it was probably too small to be felt, even directly above it. In Port Townsend, 13 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.
Earthquakes near other towns within 30 km: Sequim, Port Hadlock-Irondale, Coupeville, Oak Harbor, Ault Field, Camano.
How big was it?
This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
- Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
- Around the size people start to feel M 3.0 92× the energy of this one
- This earthquake M 1.7 about 10 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 2 earthquakes of M5 or more within 50 km:
- 5.3 Eastern Olympic Peninsula, Washington · 41 km S of this epicentre
- 5.0 6 km W of Conway, Washington · 41 km ENE 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 48.1617, -122.9215. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Island County, WA | 19 km (12 mi) | E | earthquakes near Island County |
| San Juan County, WA | 41 km (25 mi) | NNW | earthquakes near San Juan County |
| Jefferson County, WA | 60 km (37 mi) | SW | earthquakes near Jefferson County |
| Kitsap County, WA | 61 km (38 mi) | SSE | earthquakes near Kitsap County |
| Clallam County, WA | 72 km (45 mi) | W | earthquakes near Clallam County |
| Snohomish County, WA | 87 km (54 mi) | E | earthquakes near Snohomish County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
53 earthquakes have been recorded within 50 km since this one.
- 2.3 16 km SSE of Friday Harbor, Washington
- 1.7 5 km SSE of Quilcene, Washington
- 1.6 5 km N of Oak Bay, Canada
- 2.3 5 km NNE of Oak Bay, Canada
- 1.5 6 km WSW of Port Ludlow, Washington
- 1.6 8 km NE of Oak Bay, Canada
- 1.7 4 km SSW of Port Ludlow, Washington
- 1.6 5 km SSW of Port Ludlow, Washington
- 1.6 3 km N of Kingston, Washington
- 1.6 Puget Sound region, Washington
- 1.5 4 km SSW of Clinton, Washington
- 1.6 8 km NNW of Jamestown, Washington
- 1.7 4 km NE of La Conner, Washington
- 1.5 7 km WNW of Lofall, Washington
- 1.9 7 km SSW 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.