Reviewed by USGS4y ago
M4.6 earthquake in South Sandwich Islands region
Tuesday, March 22, 2022, 15:50:12 UTC · 58.168°S, 23.364°W
A magnitude 4.6 earthquake struck in South Sandwich Islands region on Tuesday, March 22, 2022, 15:50:12 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M4.7 on March 22, 2022.
- Magnitude
- 4.6
- Light · 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
27 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 50 km
USGS has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,269 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 · 113 km W of this epicenter
- 7.5South Sandwich Islands regionAugust 12, 2021 · 119 km NW of this epicenter
- 7.3South Sandwich Islands regionSeptember 1, 1961 · 233 km SW of this epicenter
- 7.2South Sandwich Islands regionNovember 15, 1910 · 110 km S of this epicenter
- 7.2South Sandwich Islands regionDecember 27, 1991 · 264 km NW of this epicenter
- 7.1South Sandwich Islands regionAugust 22, 2021 · 251 km S of this epicenter
- 7.1east of the South Sandwich IslandsAugust 26, 1977 · 216 km SE of this epicenter
- 7.1South Sandwich Islands regionDecember 11, 2018 · 181 km W 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 · 118 km away
tsunami
- 1961M7.7
South Sandwich Islands
5 Sep 1961 · 215 km away
- 1961M7.5
South Sandwich Islands
1 Sep 1961 · 271 km away
- 2021M7.5
South Sandwich Islands
12 Aug 2021 · 125 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.