3.6

M3.6 Earthquake 8 km SSW of Guánica, Puerto RicoAugust 7, 2026

2026-08-07 04:47:59 UTC (51 min ago) · approx. 12:47 AM UTC-4 local

Felt by 10 people across nearby locations.

MagnitudeM3.6(ml)
Time04:47 UTC12:47 AM UTC-4
Depth16.4 kmshallow crustal
Coordinates17.902°, -66.941°
Felt by10DYFI responses· max MMI 3.2
Status✓ Reviewed by USGS

On August 7, 2026 at 04:47 UTC, a magnitude 3.6 shallow crustal earthquake struck 8 km SSW of Guánica, Puerto Rico, at a depth of 16.4 km and coordinates 17.9024°, -66.9414°. The earthquake was reported felt by 10 peopleacross nearby locations, with a maximum shaking intensity of Modified Mercalli Intensity (MMI) 3.2 (light). This earthquake was detected by 19 seismic stations with good location accuracy and was assigned a USGS significance rating of 203, placing it among routine seismic activity.

Physical scale: An earthquake of magnitude 3.6 releases seismic energy equivalent to roughly 3.8 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 184 m — a useful intuition for the size of the slip patch on the fault.

The epicenter is located in Puerto Rico, a region characterized by the Puerto Rico Trench oblique subduction zone and the Muertos Trough, with complex Caribbean–North American plate interactions. The nearest mapped fault system is the Puerto Rico Trench. View all earthquakes in Puerto Rico.

Learn more: Magnitude scale · Aftershock sequences

Map showing earthquake epicenter at 17.90°, -66.94°

ShakeMap — predicted shaking intensity

Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.

USGS ShakeMap intensity contours for the M3.6 earthquake near 8 km SSW of Guánica, Puerto Rico

Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS

Did You Feel It? — community-reported shaking

Aggregated felt-report intensity from 10 citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.

USGS DYFI community-reported intensity map for the M3.6 earthquake near 8 km SSW of Guánica, Puerto Rico

Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report

Earthquake Details

Magnitude
3.6 ml
Depth
16.4 km
shallow crustal
Location
17.9024°N
-66.9414°E
Felt Reports
10
DYFI responses
Intensity (MMI)
3.2
light
Community Intensity
3.8
CDI from reports

Technical Information

Event ID
us6000tivs
Event Type
earthquake
Status
✓ Reviewed
Significance
203
Stations Used
19
Azimuthal Gap
109.0°
Min Station Distance
0.118°
RMS Residual
0.47 sec
Last Updated
2026-08-07 05:22:28 UTC

Common Questions

How strong was the magnitude 3.6 earthquake near Guánica, Puerto Rico?

The magnitude 3.6 earthquake that struck 8 km SSW of Guánica, Puerto Rico on August 7, 2026 at 04:47 UTC had a depth of 16.4 km. It was felt by 10 people with maximum shaking intensity of MMI 3.2 (light). For context, this was a minor earthquake typically detected only by instruments.

Where did the earthquake occur?

The earthquake epicenter was located at 17.9024°, -66.9414°, which is 8 km SSW of Guánica, Puerto Rico. View all earthquakes in Puerto Rico.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.6 earthquakes can continue for several days and gradually diminish over time.

Has Puerto Rico had earthquakes this big before?

The largest recorded earthquake in Puerto Rico was the M7.3 offshore earthquake of October 11, 1918. Today's magnitude 3.6 event is significantly smaller than that historical record.

Authoritative source: USGS event page (event ID: us6000tivs). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2026, August 7, 2026). M3.6 Earthquake 8 km SSW of Guánica, Puerto RicoAugust 7, 2026. Retrieved August 7, 2026 from https://www.earthquaketracker.org/earthquakes/event/us6000tivs/