3.4

M3.4 Earthquake 69 km NW of San Antonio, Puerto RicoDecember 31, 2024

2024-12-31 20:46:00 UTC (2024-12-31) · approx. 3:46 PM UTC-5 local

MagnitudeM3.4(md)
Time20:46 UTC3:46 PM UTC-5
Depth56.3 kmshallow crustal
Coordinates18.936°, -67.562°
Felt byNo felt reports
Status✓ Reviewed by USGS

On December 31, 2024 at 20:46 UTC, a magnitude 3.4 shallow crustal earthquake struck 69 km NW of San Antonio, Puerto Rico, at a depth of 56.3 km and coordinates 18.9357°, -67.5622°.

Physical scale: An earthquake of magnitude 3.4 releases seismic energy equivalent to roughly 1.8 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 132 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 18.94°, -67.56°

Earthquake Details

Magnitude
3.4 md
Depth
56.3 km
shallow crustal
Location
18.9357°N
-67.5622°E

Technical Information

Event ID
pr71469843
Event Type
earthquake
Status
✓ Reviewed
Significance
177
Stations Used
8
Azimuthal Gap
212.0°
Min Station Distance
0.632°
RMS Residual
0.47 sec
Last Updated
2024-12-31 21:18:42 UTC

Common Questions

How strong was the magnitude 3.4 earthquake near San Antonio, Puerto Rico?

The magnitude 3.4 earthquake that struck 69 km NW of San Antonio, Puerto Rico on December 31, 2024 at 20:46 UTC had a depth of 56.3 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.4 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.4 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: pr71469843). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2024, December 31, 2024). M3.4 Earthquake 69 km NW of San Antonio, Puerto RicoDecember 31, 2024. Retrieved December 31, 2024 from https://www.earthquaketracker.org/earthquakes/event/pr71469843/