Reviewed by USGS34y ago
M5.6 earthquake in South Sandwich Islands region
Sunday, January 17, 1993, 18:24:51 UTC · 58.634°S, 26.177°W
A magnitude 5.6 earthquake struck in South Sandwich Islands region on Sunday, January 17, 1993, 18:24:51 UTC, at a depth of 110.2 km (intermediate). It is the strongest earthquake within 300 km since an M6.7 on January 10, 1993.
- Magnitude
- 5.6
- Moderate · mw
- Depth
- 110 km
- Intermediate
- 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
4 kilotons of TNT
That is about 1/4 of the Hiroshima bomb. It released about 8 times the energy of a magnitude 5.0.
Tectonic setting
127 km
from the nearest mapped plate boundary, between the Sandwich and South American plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
110 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
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 571 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8South Sandwich Islands regionMay 26, 1964 · 272 km N of this epicenter
- 7.5South Sandwich Islands regionAugust 28, 1933 · 187 km S of this epicenter
- 7.3South Sandwich Islands regionSeptember 1, 1961 · 80 km SW of this epicenter
- 7.2South Sandwich Islands regionNovember 15, 1910 · 139 km SE of this epicenter
- 7.2South Sandwich Islands regionDecember 27, 1991 · 294 km N of this epicenter
- 7.2South Sandwich Islands regionOctober 22, 1983 · 229 km S of this epicenter
- 7.1South Sandwich Islands regionSeptember 8, 1961 · 265 km N of this epicenter
- 7.0South Sandwich Islands regionJanuary 30, 1987 · 164 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:
- 1961M7.7
South Sandwich Islands
5 Sep 1961 · 85 km away
- 1961M7.7
South Sandwich Islands
8 Sep 1961 · 272 km away
- 1961M7.5
South Sandwich Islands
1 Sep 1961 · 116 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.