Reviewed by USGS11y ago
M5.3 earthquake in South Sandwich Islands region
Monday, July 13, 2015, 20:16:08 UTC · 55.997°S, 28.266°W
A magnitude 5.3 earthquake struck in South Sandwich Islands region on Monday, July 13, 2015, 20:16:08 UTC, at a depth of 138.5 km (intermediate). It is the strongest earthquake within 300 km since an M5.4 on May 4, 2015.
- Magnitude
- 5.3
- Moderate · mb
- Depth
- 139 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 earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
1 kilotons of TNT
That is about 1/11 of the Hiroshima bomb. It released about 3 times the energy of a magnitude 5.0.
Tectonic setting
103 km
from the nearest mapped plate boundary, between the Sandwich and Scotia plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
139 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 lists 6 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.9 on July 26, 2015. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.7South Sandwich Islands region11y ago · 37 km E of this epicenter
- 4.5South Sandwich Islands region11y ago · 41 km NW of this epicenter
- 4.6South Sandwich Islands region11y ago · 44 km E of this epicenter
- 4.9South Sandwich Islands region11y ago · 57 km NE of this epicenter
- 4.6South Sandwich Islands region11y ago · 65 km E of this epicenter
- 4.9South Sandwich Islands region11y ago · 50 km E of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,007 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 · 97 km NW of this epicenter
- 7.8South Sandwich Islands regionMay 26, 1964 · 52 km SE of this epicenter
- 7.2South Sandwich Islands regionDecember 27, 1991 · 186 km E of this epicenter
- 7.1South Sandwich Islands regionSeptember 8, 1961 · 68 km SE of this epicenter
- 6.9South Sandwich Islands regionAugust 18, 1930 · 29 km NE of this epicenter
- 6.9South Sandwich Islands regionSeptember 13, 1921 · 48 km NW of this epicenter
- 6.9South Sandwich Islands regionSeptember 6, 2004 · 83 km NW of this epicenter
- 6.9South Sandwich Islands regionJune 29, 2014 · 59 km N 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 · 97 km away
- 1961M7.7
South Sandwich Islands
5 Sep 1961 · 236 km away
- 1961M7.7
South Sandwich Islands
8 Sep 1961 · 68 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.