Reviewed by USGS21y ago
M7.4 earthquake east of the South Sandwich Islands
Monday, January 2, 2006, 06:10:49 UTC · 60.957°S, 21.606°W
A magnitude 7.4 earthquake struck east of the South Sandwich Islands on Monday, January 2, 2006, 06:10:49 UTC, at a depth of 13.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 7.4
- Major · mwc
- Depth
- 13 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: 200 km aftershock search area
In context
How big was it, and why here?
Energy released
1.9 megatons of TNT
That is about 126 times the Hiroshima bomb. It released about 3,981 times the energy of a magnitude 5.0.
Tectonic setting
23 km
from the nearest mapped plate boundary, between the Antarctic and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
13 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 200 km
USGS lists 2 M2.5+ earthquakes within 200 km in the following 30 days; the largest was M4.8 on January 2, 2006. 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 221 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.2South Sandwich Islands regionNovember 15, 1910 · 243 km NW of this epicenter
- 7.2South Sandwich Islands regionOctober 22, 1983 · 211 km W of this epicenter
- 7.1east of the South Sandwich IslandsAugust 26, 1977 · 181 km N of this epicenter
- 7.0east of the South Sandwich IslandsOctober 6, 1973 · 15 km N of this epicenter
- 7.0South Sandwich Islands regionDecember 14, 1959 · 280 km W of this epicenter
- 7.0South Sandwich Islands regionMarch 21, 1926 · 120 km W of this epicenter
- 6.7South Sandwich Islands regionAugust 22, 1967 · 149 km W of this epicenter
- 6.7east of the South Sandwich IslandsMay 7, 1982 · 56 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1973M7.5
Antarctica
6 Oct 1973 · 16 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.