Reviewed by USGS50y ago
M4.8 earthquake in Easter Island region
Saturday, July 31, 1976, 05:55:43 UTC · 22.745°S, 113.182°W
A magnitude 4.8 earthquake struck in Easter Island region on Saturday, July 31, 1976, 05:55:43 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M5.1 on July 29, 1976.
- Magnitude
- 4.8
- Light · ms
- Depth
- 33 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
239 tons of TNT
That is about 1/63 of the Hiroshima bomb. A magnitude 5.0 releases about 2 times more energy.
Tectonic setting
45 km
from the nearest mapped plate boundary, between the Easter and Nazca plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
33 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 50 km
USGS has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 25 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.5Easter Island regionNovember 2, 1932 · 96 km E of this epicenter
- 6.3southern East Pacific RiseApril 8, 1954 · 214 km W of this epicenter
- 6.3Easter Island regionApril 30, 1950 · 242 km S of this epicenter
- 6.3Easter Island regionJuly 23, 1956 · 171 km SE of this epicenter
- 6.2southern East Pacific RiseFebruary 20, 1951 · 183 km NW of this epicenter
- 6.2southern East Pacific RiseJuly 26, 1976 · 94 km N of this epicenter
- 6.2Easter Island regionApril 23, 1955 · 228 km S of this epicenter
- 6.1Easter Island regionJuly 18, 1952 · 146 km W of this epicenter