Reviewed by USGS92y ago
M6.0 earthquake north of Ascension Island
Wednesday, July 17, 1935, 04:31:39 UTC · 1.222°S, 15.770°W
A magnitude 6.0 earthquake struck north of Ascension Island on Wednesday, July 17, 1935, 04:31:39 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.7 on May 19, 1933.
- Magnitude
- 6.0
- Strong · 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
16 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 33 times the energy of a magnitude 5.0.
Tectonic setting
11 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 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 11 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.7north of Ascension IslandMay 19, 1933 · 71 km E of this epicenter
- 6.5north of Ascension IslandJuly 20, 1923 · 194 km E of this epicenter
- 6.3north of Ascension IslandJune 6, 1929 · 98 km E of this epicenter
- 6.3north of Ascension IslandDecember 28, 1918 · 134 km E of this epicenter
- 6.2north of Ascension IslandOctober 28, 1917 · 243 km E of this epicenter
- 6.1north of Ascension IslandAugust 3, 1928 · 166 km SE of this epicenter
- 6.0central Mid-Atlantic RidgeMarch 16, 1917 · 274 km W of this epicenter
- 6.0north of Ascension IslandJuly 4, 1920 · 65 km NE of this epicenter