M4.0 earthquake 10 km SSW of Seabeck, Washington
A magnitude 4.0 earthquake struck 10 km SSW of Seabeck, Washington on Wed, Apr 16, 1975, 12:09 PM PDT (19:09 UTC), 40 km (25 mi) below the surface.
A larger quake followed: M4.2 2 km SW of DuPont, Washington. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.0 (md), light
- Local time
- UTC
- 1975-04-16 19:09:29 UTC
- Depth
- 39.9 km (24.8 mi), shallow
- Epicenter
- 47.556° N, 122.904° W
- Region
- Washington
- Tsunami flag
- No
- Status
- Reviewed by a seismologist
Did you feel it?
No one has reported feeling this quake to the USGS.
How well it is located
Reviewed by a seismologist.
- Location uncertainty
- About 0.8 km horizontally, 0.8 km in depth
- Magnitude uncertainty
- ±0.08
- Depth from
- From location
- Station coverage gap
- 122°
- Stations used
- 8
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 10 in the 60 days after this one and 5 in the 30 days before it.
After
- 4.22 km SW of DuPont, Washington · 18780 days ago · 45 km deep · 56 km away
- 2.05 km NNE of Startup, Washington · 18771 days ago · 26 km deep · 97 km away
- 1.71 km NNE of Snoqualmie, Washington · 18752 days ago · 8 km deep · 82 km away
- 1.55 km S of Fall City, Washington · 18748 days ago · 18 km deep · 76 km away
- 1.75 km SSE of Keyport, Washington · 18744 days ago · 18 km deep · 25 km away
- 1.92 km N of White Center, Washington · 18737 days ago · 22 km deep · 41 km away
- 1.71 km ENE of Quilcene, Washington · 18735 days ago · 48 km deep · 30 km away
- 1.74 km WSW of Woodway, Washington · 18734 days ago · 12 km deep · 43 km away
- 1.51 km SW of Lynnwood, Washington · 18732 days ago · 5 km deep · 51 km away
- 1.72 km W of Suquamish, Washington · 18729 days ago · 3 km deep · 31 km away
Before
- 2.817 km ESE of Carbonado, Washington · 18793 days ago · -1 km deep · 99 km away
- 2.22 km NNE of Riverton, Washington · 18801 days ago · 25 km deep · 47 km away
- 1.88 km W of Longbranch, Washington · 18802 days ago · 8 km deep · 40 km away
- 2.13 km NE of Dash Point, Washington · 18804 days ago · 14 km deep · 46 km away
- 2.83 km NW of Black Diamond, Washington · 18815 days ago · 20 km deep · 70 km away
Earthquakes todayWashington earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event uw10860693 (also filed as usp0000an7). Read Tue, Sep 22, 2026, 9:10 AM UTC.