4.1

M4.1 Earthquake in the South Sandwich Islands regionJuly 12, 2023

2023-07-12 23:20:20 UTC (2023-07-12) · approx. 9:20 PM UTC-2 local

MagnitudeM4.1(mb)
Time23:20 UTC9:20 PM UTC-2
Depth10.0 kmshallow crustal
Coordinates-59.382°, -29.290°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 12, 2023 at 23:20 UTC, a magnitude 4.1 shallow crustal earthquake struck in the South Sandwich Islands region, at a depth of 10.0 km and coordinates -59.3815°, -29.2895°.

Physical scale: An earthquake of magnitude 4.1 releases seismic energy equivalent to roughly 21 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 406 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at -59.38°, -29.29°

Earthquake Details

Magnitude
4.1 mb
Depth
10.0 km
shallow crustal
Location
-59.3815°N
-29.2895°E

Technical Information

Event ID
us7000kh2p
Event Type
earthquake
Status
✓ Reviewed
Significance
259
Stations Used
12
Azimuthal Gap
109.0°
Min Station Distance
16.274°
RMS Residual
0.94 sec
Last Updated
2023-09-16 19:16:23 UTC

Common Questions

How strong was the magnitude 4.1 earthquake in the South Sandwich Islands region?

The magnitude 4.1 earthquake that struck in the South Sandwich Islands region on July 12, 2023 at 23:20 UTC had a depth of 10.0 km. For context, this was a light earthquake commonly felt near the epicenter.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 4.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 4.1 earthquakes are often felt but rarely cause damage.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000kh2p). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, July 12, 2023). M4.1 Earthquake in the South Sandwich Islands regionJuly 12, 2023. Retrieved September 16, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kh2p/