M3.6 Earthquake 91 km N of Isabela, Puerto Rico — October 17, 2025
2025-10-17 23:56:00 UTC (2025-10-17) · approx. 7:56 PM UTC-4 local
On October 17, 2025 at 23:56 UTC, a magnitude 3.6 shallow crustal earthquake struck 91 km N of Isabela, Puerto Rico, at a depth of 29.0 km and coordinates 19.3265°, -67.0645°.0
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.
Did You Feel It? — community-reported shaking
Aggregated felt-report intensity from submitted citizen responses to the USGS Did You Feel It? system. Each colored zone represents the average MMI from reports in that area.
Source: U.S. Geological Survey Did You Feel It?. View on USGS · submit your own report
Earthquake Details
-67.0645°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.6 earthquake near Isabela, Puerto Rico?
The magnitude 3.6 earthquake that struck 91 km N of Isabela, Puerto Rico on October 17, 2025 at 23:56 UTC had a depth of 29.0 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 3.6 earthquakes can continue for several days and gradually diminish over time.
What should I do after an earthquake?
If you were in the affected area: check yourself and others for injuries, inspect your home for damage, and be prepared for aftershocks. For detailed guidance, see our earthquake safety guide and emergency planning resources.
Actions
Understanding This Data
Magnitude 3.6 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: pr2025290000). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2025, October 17, 2025). M3.6 Earthquake 91 km N of Isabela, Puerto Rico — October 17, 2025. Retrieved May 27, 2026 from https://www.earthquaketracker.org/earthquakes/event/pr2025290000/