5.1

M5.1 Earthquake in the South Sandwich Islands regionMarch 20, 2023

2023-03-20 11:57:15 UTC (2023-03-20) · approx. 9:57 AM UTC-2 local

MagnitudeM5.1(mb)
Time11:57 UTC9:57 AM UTC-2
Depth131.0 kmintermediate depth
Coordinates-56.076°, -27.866°
Felt byNo felt reports
Status✓ Reviewed by USGS

On March 20, 2023 at 11:57 UTC, a magnitude 5.1 intermediate depth earthquake struck in the South Sandwich Islands region, at a depth of 131.0 km and coordinates -56.0760°, -27.8664°. This earthquake was detected by 67 seismic stations with excellent location accuracy and was assigned a USGS significance rating of 400, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 5.1 releases seismic energy equivalent to roughly 674 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 2.0 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 -56.08°, -27.87°

Earthquake Details

Magnitude
5.1 mb
Depth
131.0 km
intermediate depth
Location
-56.0760°N
-27.8664°E

Technical Information

Event ID
us7000jlef
Event Type
earthquake
Status
✓ Reviewed
Significance
400
Stations Used
67
Azimuthal Gap
42.0°
Min Station Distance
5.257°
RMS Residual
0.57 sec
Last Updated
2023-05-26 21:54:07 UTC

Common Questions

How strong was the magnitude 5.1 earthquake in the South Sandwich Islands region?

The magnitude 5.1 earthquake that struck in the South Sandwich Islands region on March 20, 2023 at 11:57 UTC had a depth of 131.0 km. For context, this was a moderate earthquake that could be widely felt.

Where did the earthquake occur?

The earthquake epicenter was located at -56.0760°, -27.8664°, which is in the South Sandwich Islands region.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 5.1 earthquakes can continue for days to weeks and gradually diminish over time.

Authoritative source: USGS event page (event ID: us7000jlef). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, March 20, 2023). M5.1 Earthquake in the South Sandwich Islands regionMarch 20, 2023. Retrieved May 26, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000jlef/