3.2

M3.2 Earthquake 40 km NNW of San Antonio, Puerto RicoJuly 20, 2026

2026-07-20 20:06:58 UTC (11 hours ago) · approx. 4:06 PM UTC-4 local

MagnitudeM3.2(md)
Time20:06 UTC4:06 PM UTC-4
Depth17.5 kmshallow crustal
Coordinates18.840°, -67.217°
Felt byNo felt reports
Status✓ Reviewed by USGS

On July 20, 2026 at 20:06 UTC, a magnitude 3.2 shallow crustal earthquake struck 40 km NNW of San Antonio, Puerto Rico, at a depth of 17.5 km and coordinates 18.8402°, -67.2170°.

Physical scale: An earthquake of magnitude 3.2 releases seismic energy equivalent to roughly 1.1 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 104 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 18.84°, -67.22°

Earthquake Details

Magnitude
3.2 md
Depth
17.5 km
shallow crustal
Location
18.8402°N
-67.2170°E

Technical Information

Event ID
pr71525208
Event Type
earthquake
Status
✓ Reviewed
Significance
162
Stations Used
16
Azimuthal Gap
294.0°
Min Station Distance
0.348°
RMS Residual
0.22 sec
Last Updated
2026-07-20 20:22:39 UTC

Common Questions

How strong was the magnitude 3.2 earthquake near San Antonio, Puerto Rico?

The magnitude 3.2 earthquake that struck 40 km NNW of San Antonio, Puerto Rico on July 20, 2026 at 20:06 UTC had a depth of 17.5 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 3.2 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.2 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: pr71525208). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, July 20, 2026). M3.2 Earthquake 40 km NNW of San Antonio, Puerto RicoJuly 20, 2026. Retrieved July 20, 2026 from https://www.earthquaketracker.org/earthquakes/event/pr71525208/