Reviewed by USGS5d ago
M5.0 earthquake in South Sandwich Islands region
Monday, September 21, 2026, 21:37:04 UTC · 56.518°S, 24.161°W
A magnitude 5.0 earthquake struck in South Sandwich Islands region on Monday, September 21, 2026, 21:37:04 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M5.0 on September 19, 2026.
- Magnitude
- 5.0
- Moderate · mb
- Depth
- 10 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
477 tons of TNT
That is about 1/32 of the Hiroshima bomb. Each whole step in magnitude is about 32 times more energy.
Tectonic setting
40 km
from the nearest mapped plate boundary, between the Sandwich and South American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 has not published any M2.5+ earthquake within 75 km since this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,752 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.12021 South Sandwich Islands EarthquakeAugust 12, 2021 · 217 km S of this epicenter
- 7.8South Sandwich Islands regionMay 26, 1964 · 216 km W of this epicenter
- 7.5South Sandwich Islands regionAugust 12, 2021 · 128 km SW of this epicenter
- 7.2South Sandwich Islands regionNovember 15, 1910 · 289 km S of this epicenter
- 7.2South Sandwich Islands regionDecember 27, 1991 · 87 km NW of this epicenter
- 7.2South Sandwich Islands regionMay 28, 2016 · 174 km W of this epicenter
- 7.1South Sandwich Islands regionSeptember 8, 1961 · 197 km W of this epicenter
- 7.1South Sandwich Islands regionDecember 11, 2018 · 262 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 4 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 2021M8.1
South Sandwich Islands
12 Aug 2021 · 222 km away
tsunami
- 1961M7.7
South Sandwich Islands
5 Sep 1961 · 237 km away
- 1961M7.7
South Sandwich Islands
8 Sep 1961 · 194 km away
- 2021M7.5
South Sandwich Islands
12 Aug 2021 · 135 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.