Reviewed by USGS71y ago
M7.0 earthquake south of Tonga
Tuesday, January 10, 1956, 08:52:43 UTC · 26.430°S, 175.241°W
A magnitude 7.0 earthquake struck south of Tonga on Tuesday, January 10, 1956, 08:52:43 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M7.5 on February 27, 1955.
- Magnitude
- 7.0
- Strong · mw
- Depth
- 35 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: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
461 kilotons of TNT
That is about 31 times the Hiroshima bomb. It released about 966 times the energy of a magnitude 5.0.
Tectonic setting
18 km
from the nearest mapped plate boundary, between the Kermadec and Pacific plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
35 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 lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.0 on January 27, 1956. 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 32 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.5Kermadec Islands regionFebruary 27, 1955 · 215 km S of this epicenter
- 7.4south of TongaMarch 18, 1905 · 295 km NE of this epicenter
- 6.8south of TongaApril 19, 1905 · 187 km E of this epicenter
- 6.7south of the Fiji IslandsSeptember 8, 1920 · 249 km NW of this epicenter
- 6.7Kermadec Islands regionDecember 12, 1928 · 220 km SW of this epicenter
- 6.7Kermadec Islands regionMay 4, 1917 · 167 km SW of this epicenter
- 6.6Kermadec Islands regionFebruary 13, 1925 · 286 km S of this epicenter
- 6.5Kermadec Islands regionJuly 27, 1949 · 270 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1955M7.8
Kermadec Islands
27 Feb 1955 · 176 km away
- 1905M7.5
Kermadec Islands
18 Mar 1905 · 252 km away
- 1956M7.0
Tonga Islands
10 Jan 1956 · 48 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.