M4.9 earthquake 57 km WNW of Vallenar, Chile
A magnitude 4.9 earthquake struck 57 km WNW of Vallenar, Chile on Thu, Aug 4, 1977, 2:45 AM GMT-4 (06:45 UTC), 33 km (21 mi) below the surface.
A larger quake followed: M5.0 70 km WSW of Copiapó, Chile. This one was a foreshock.
Map
Where this earthquake was located, with the others nearby. Select one for its page.
The earthquake
- Magnitude
- 4.9 (mb), light
- Local time
- UTC
- 1977-08-04 06:45:39 UTC
- Depth
- 33.0 km (20.5 mi), shallow
- Epicenter
- 28.353° S, 71.287° W
- Region
- Chile
- 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.
- Depth from
- OPERATOR_ASSIGNED
- Stations used
- 35
Nearest places
Distance and direction from each place to the epicenter, with its forecast.
Nearby
Within 100 km, magnitude 1.9 and up: 1 in the 60 days after this one and 0 in the 30 days before it.
After
Earthquakes todayChile earthquakesLive radar here
Sources
From the USGS Earthquake Hazards Program and its partner networks, event usp0000pzb. Read Tue, Sep 22, 2026, 10:17 AM UTC.