Reviewed by USGS10y ago
M4.9 earthquake in South Sandwich Islands region
Saturday, September 17, 2016, 08:28:54 UTC · 54.847°S, 30.537°W
A magnitude 4.9 earthquake struck in South Sandwich Islands region on Saturday, September 17, 2016, 08:28:54 UTC, at a depth of 10.0 km (shallow). It is the strongest earthquake within 300 km since an M5.3 on September 16, 2016.
- Magnitude
- 4.9
- 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 earthquakeDashed circle: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
338 tons of TNT
That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.
Tectonic setting
3 km
from the nearest mapped plate boundary, between the Scotia 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 lists 25 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.2 on September 21, 2016. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.3South Sandwich Islands region10y ago · 43 km S of this epicenter
- 4.8South Sandwich Islands region10y ago · 13 km W of this epicenter
- 4.9South Sandwich Islands region10y ago · 23 km NW of this epicenter
- 5.0South Sandwich Islands region10y ago · 6 km NW of this epicenter
- 5.0South Sandwich Islands region10y ago · 13 km SW of this epicenter
- 4.9South Sandwich Islands region10y ago · 9 km NW of this epicenter
- 4.7South Sandwich Islands region10y ago · 9 km NW of this epicenter
- 4.5South Georgia Island region10y ago · 41 km W of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 698 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11929 South Sandwich Islands EarthquakeJune 27, 1929 · 96 km SE of this epicenter
- 7.8South Sandwich Islands regionMay 26, 1964 · 244 km SE of this epicenter
- 7.4South Georgia Island regionAugust 19, 2016 · 98 km SW of this epicenter
- 7.2South Sandwich Islands regionMay 28, 2016 · 274 km SE of this epicenter
- 7.1South Sandwich Islands regionSeptember 8, 1961 · 260 km SE of this epicenter
- 6.9South Sandwich Islands regionAugust 18, 1930 · 193 km SE of this epicenter
- 6.9South Sandwich Islands regionSeptember 13, 1921 · 147 km SE of this epicenter
- 6.9South Sandwich Islands regionSeptember 6, 2004 · 115 km SE 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:
- 1929M8.1
South Sandwich Islands
27 Jun 1929 · 96 km away
- 1961M7.7
South Sandwich Islands
8 Sep 1961 · 258 km away
- 2016M7.4
South Sandwich Islands
19 Aug 2016 · 98 km away · intensity III
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.