M4.2 earthquake 39 km E of Pedro Bay, Alaska
A magnitude 4.2 earthquake struck 39 km E of Pedro Bay, Alaska on Fri, Sep 1, 1978, 8:38 AM GMT-9 (17:38 UTC), 139 km (86 mi) below the surface.
A larger quake followed: M4.7 58 km ENE of Pedro Bay, Alaska. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.2 (mb), light
- Local time
- UTC
- 1978-09-01 17:38:52 UTC
- Depth
- 139.0 km (86.4 mi), intermediate-depth
- Epicenter
- 59.755° N, 153.409° 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
- 29
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.5 and up: 2 in the 60 days after this one and 3 in the 30 days before it.
After
- 3.743 km SW of Nanwalek, Alaska · 17553 days ago · 77 km deep · 87 km away
- 4.758 km ENE of Pedro Bay, Alaska · 17539 days ago · 128 km deep · 28 km away
Before
Earthquakes todayAlaska earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0000wan. Read Tue, Sep 22, 2026, 9:14 AM UTC.