Reviewed by USGS70y ago
M5.9 earthquake northern Mid-Atlantic Ridge
Tuesday, February 5, 1957, 04:51:26 UTC · 25.689°N, 45.260°W
A magnitude 5.9 earthquake struck northern Mid-Atlantic Ridge on Tuesday, February 5, 1957, 04:51:26 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.0 on May 23, 1935.
- 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 earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
12 kilotons of TNT
That is about the energy of the Hiroshima bomb. It released about 25 times the energy of a magnitude 5.0.
Tectonic setting
2 km
from the nearest mapped plate boundary, between the North American and African 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 lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M5.8 on February 18, 1957. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 9 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.8northern Mid-Atlantic RidgeJanuary 9, 1922 · 217 km S of this epicenter
- 6.2northern Mid-Atlantic RidgeOctober 14, 1924 · 184 km S of this epicenter
- 6.0northern Mid-Atlantic RidgeMay 23, 1935 · 270 km S of this epicenter
- 5.9northern Mid-Atlantic RidgeAugust 12, 1925 · 248 km S of this epicenter
- 5.8northern Mid-Atlantic RidgeDecember 13, 1937 · 127 km NE of this epicenter
- 5.7northern Mid-Atlantic RidgeMarch 6, 1927 · 278 km NE of this epicenter
- 5.7northern Mid-Atlantic RidgeMay 27, 1951 · 210 km S of this epicenter
- 5.7northern Mid-Atlantic RidgeJune 6, 1936 · 236 km NE of this epicenter