3.1

M3.1 Earthquake 73 km NW of San Antonio, Puerto RicoMay 31, 2023

2023-05-31 23:33:03 UTC (2023-05-31) · approx. 6:33 PM UTC-5 local

MagnitudeM3.1(md)
Time23:33 UTC6:33 PM UTC-5
Depth5.6 kmshallow crustal
Coordinates18.892°, -67.658°
Felt byNo felt reports
Status✓ Reviewed by USGS

On May 31, 2023 at 23:33 UTC, a magnitude 3.1 shallow crustal earthquake struck 73 km NW of San Antonio, Puerto Rico, at a depth of 5.6 km and coordinates 18.8915°, -67.6578°.

Physical scale: An earthquake of magnitude 3.1 releases seismic energy equivalent to roughly 674 kg of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 83 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 18.89°, -67.66°

Earthquake Details

Magnitude
3.1 md
Depth
5.6 km
shallow crustal
Location
18.8915°N
-67.6578°E

Technical Information

Event ID
pr71411908
Event Type
earthquake
Status
✓ Reviewed
Significance
148
Stations Used
11
Azimuthal Gap
228.0°
Min Station Distance
0.532°
RMS Residual
0.28 sec
Last Updated
2023-08-05 22:07:43 UTC

Common Questions

How strong was the magnitude 3.1 earthquake near San Antonio, Puerto Rico?

The magnitude 3.1 earthquake that struck 73 km NW of San Antonio, Puerto Rico on May 31, 2023 at 23:33 UTC had a depth of 5.6 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 3.1 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.1 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: pr71411908). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2023, May 31, 2023). M3.1 Earthquake 73 km NW of San Antonio, Puerto RicoMay 31, 2023. Retrieved August 5, 2023 from https://www.earthquaketracker.org/earthquakes/event/pr71411908/