5.3

M5.3 Earthquake in the South Sandwich Islands regionMarch 20, 2025

2025-03-20 12:04:21 UTC (2025-03-20) · approx. 10:04 AM UTC-2 local

MagnitudeM5.3(mb)
Time12:04 UTC10:04 AM UTC-2
Depth117.9 kmintermediate depth
Coordinates-56.251°, -27.003°
Felt byNo felt reports
Status✓ Reviewed by USGS

On March 20, 2025 at 12:04 UTC, a magnitude 5.3 intermediate depth earthquake struck in the South Sandwich Islands region, at a depth of 117.9 km and coordinates -56.2513°, -27.0028°. This earthquake was detected by 87 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 432, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.3 releases seismic energy equivalent to roughly 1 kilotons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.7 km — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in South Sandwich Islands, a region characterized by the South Sandwich Trench, one of Earth's most remote subduction zones.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at -56.25°, -27.00°

Earthquake Details

Magnitude
5.3 mb
Depth
117.9 km
intermediate depth
Location
-56.2513°N
-27.0028°E

Technical Information

Event ID
us6000q001
Event Type
earthquake
Status
✓ Reviewed
Significance
432
Stations Used
87
Azimuthal Gap
30.0°
Min Station Distance
5.770°
RMS Residual
1.01 sec
Last Updated
2025-05-29 17:36:25 UTC

Common Questions

How strong was the magnitude 5.3 earthquake in the South Sandwich Islands region?

The magnitude 5.3 earthquake that struck in the South Sandwich Islands region on March 20, 2025 at 12:04 UTC had a depth of 117.9 km. For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at -56.2513°, -27.0028°, which is in the South Sandwich Islands region.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.3 earthquakes can continue for days to weeks and gradually diminish over time.

Authoritative source: USGS event page (event ID: us6000q001). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, March 20, 2025). M5.3 Earthquake in the South Sandwich Islands regionMarch 20, 2025. Retrieved May 29, 2025 from https://www.earthquaketracker.org/earthquakes/event/us6000q001/