Reviewed by USGS75y ago
M5.9 earthquake in Ascension Island region
Thursday, March 27, 1952, 16:10:02 UTC · 7.138°S, 11.467°W
A magnitude 5.9 earthquake struck in Ascension Island region on Thursday, March 27, 1952, 16:10:02 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.1 on November 8, 1922.
- Magnitude
- 5.9
- Moderate · mw
- Depth
- 15 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
11 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 23 times the energy of a magnitude 5.0.
Tectonic setting
33 km
from the nearest mapped plate boundary, between the African and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 4 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.1245 km ENE of Georgetown, Saint HelenaNovember 8, 1922 · 112 km W of this epicenter
- 5.9Ascension Island regionApril 30, 1932 · 158 km N of this epicenter
- 5.7180 km E of Georgetown, Saint HelenaAugust 1, 1932 · 160 km SW of this epicenter
- 5.6212 km ENE of Georgetown, Saint HelenaAugust 21, 1951 · 140 km W of this epicenter