Earthquakes in Puerto Rico — October 2026

28 earthquakes were recorded in Puerto Rico during October 2026, an average of 0.9 per day.

0 reached magnitude 4 or above and 0 reached magnitude 5 or above. The average focal depth was 16 km.

The month's largest event in Puerto Rico was a magnitude 3.9 earthquake near Rincón, Puerto Rico on 03 October 2026 at 10:35 UTC. A magnitude 3.9 earthquake radiates roughly 11 tons of TNT equivalent in seismic energy.

That is below the Puerto Rico monthly average of 173 events over the period we cover — a comparatively quiet month, and down from the 283 recorded the previous month.

96% of events here are shallow (under 70 km), 4% intermediate (70–300 km) and 0% deep-focus (over 300 km). Almost everything here is crustal. That is characteristic of transform faulting or continental deformation rather than subduction — and it means shaking at the surface is strong for the magnitudes involved.

By band, the catalogue holds 5 in the magnitude 1 range, 19 in the magnitude 2 range, 4 in the magnitude 3 range.

Activity peaked on 03 October, when 8 events were recorded.

The month's largest events were M3.9 near Rincón, Puerto Rico on 03 October at 10 km; M3.9 near Rincón, Puerto Rico on 03 October at 6 km; M3.4 near Corozal, Puerto Rico on 03 October at 111 km.

That is 84% below the 173 events Puerto Rico averages per month across the 23 months on record.