M3.9 earthquake 47 km WNW of Nanwalek, Alaska
A magnitude 3.9 earthquake struck 47 km WNW of Nanwalek, Alaska on Sat, Apr 15, 1978, 10:49 PM GMT-10 (08:49 UTC), 87 km (54 mi) below the surface.
A larger quake followed: M4.6 43 km E of Port Alsworth, Alaska. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 3.9 (mb), minor
- Local time
- UTC
- 1978-04-16 08:49:17 UTC
- Depth
- 87.0 km (54.1 mi), intermediate-depth
- Epicenter
- 59.499° N, 152.716° W
- Region
- Alaska
- 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.
- Stations used
- 35
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 5 in the 60 days after this one and 3 in the 30 days before it.
After
- 4.643 km E of Port Alsworth, Alaska · 17689 days ago · 158 km deep · 84 km away
- 4.18 km NW of Happy Valley, Alaska · 17686 days ago · 92 km deep · 75 km away
- 4.546 km NE of Pedro Bay, Alaska · 17683 days ago · 171 km deep · 74 km away
- 4.150 km NE of Pedro Bay, Alaska · 17649 days ago · 152 km deep · 76 km away
- 3.284 km SE of Kokhanok, Alaska · 17642 days ago · 13 km deep · 87 km away
Before
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0000u4n. Read Tue, Sep 22, 2026, 9:01 PM UTC.