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M3.0 earthquake 3 km SW of Guayanilla, Puerto Rico

A magnitude 3.0 earthquake struck 3 km SW of Guayanilla, Puerto Rico at 03:56 local time (07:56 UTC) on 17 Sept 2026, at a depth of 12 km, according to USGS.

Data: USGS · updated 2026-09-17 08:58 UTC · reviewed

Magnitude
3.0minor
duration magnitude (md)
Depth
12.1 km
Status
Reviewed
Origin time
2026-09-17 07:56:27 UTC
Local: 17 Sept 2026, 03:56:27 (America/Puerto Rico)
Epicentre
17.996° N, 66.809° W

Circles show this event and others within 30 km from 7 days before to 30 days after. Lines: plate boundaries and GEM active faults. Open on the live map

Nearby places

Distance and estimated shaking at nearby places
PlaceDistanceEst. shaking
GuayanillaPuerto Rico · pop. 5,2133 kmIIIWeak
YaucoPuerto Rico · pop. 20,2956 kmIIIWeak
PoncePuerto Rico · pop. 137,49120 kmIIWeak
MayagüezPuerto Rico · pop. 73,07742 kmINot felt
AreciboPuerto Rico · pop. 87,75453 kmINot felt
San JuanPuerto Rico · pop. 418,14091 kmINot felt
Santo Domingo EsteSanto Domingo Province, Dominican Republic · pop. 700,000326 kmINot felt
Santo DomingoNacional, Dominican Republic · pop. 2,201,941330 kmINot felt

Shaking is an estimate from the intensity prediction equation of Allen, Wald & Worden (2012), not an observation. Local ground and buildings can change it by a level or more. Likely felt out to about 11 km.

Every agency's solution

Agencies locate earthquakes with their own stations and methods, so their numbers differ. We match reports of the same event by time, distance and magnitude and show them side by side. The headline uses USGS · PR, which has been reviewed by an analyst.

AgencyMagnitudeDepthEpicentreTime offsetStatus
USGS · PRheadlinePuerto Rico Seismic Network via U.S. Geological Survey3.0 md12.1 km18.00° N, 66.81° W–Reviewed

How big was it?

Often felt by people at rest close to the epicentre, rarely causes damage.

It released roughly the energy of 567 kg of TNT. Magnitude is logarithmic: each whole step means about 32 times more energy and 10 times larger waves on a seismogram. Depth matters too: at 12 km this was a shallow earthquake, which is felt more strongly at the surface than a deeper one of the same size.

M3.0 releases about 27× the energy of M2.1, and its waves are about 8.9× taller on a seismogram. Energy: 567 kg of TNT vs 21 kg of TNT.

Each square is the energy of one M2.1. Energy from log₁₀E = 1.5M + 4.8.

Aftershocks and nearby activity

66 later earthquakes within 30 km; the largest was M4.8 10 days ago. 4 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.

Aftershocks

Mainshock M3.0

66 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).

Aftershocks
Time after mainshock (hours)MagnitudeDepth (km)
20.122.56
29.394.87
29.442.58
29.652.910
30.202.68
30.292.59
33.012.68
33.022.78
33.403.46
34.452.88
34.472.56
35.472.76
35.543.07
37.752.58
38.322.57
38.532.67
43.262.59
43.292.513
43.622.57
44.883.07
45.183.18
45.583.18
47.093.014
56.582.88
62.842.69
64.292.57
71.943.014
84.603.08
87.702.57
112.572.111
113.112.215
115.561.415
117.152.017
117.182.115
125.811.811
126.792.17
127.821.87
131.412.28
137.122.18
139.292.27
140.992.117
142.322.57
153.081.78
154.332.314
156.912.18
156.992.37
159.342.08
163.581.99
179.332.112
181.422.68
181.602.118
182.332.46
184.362.37
194.342.09
197.082.17
220.562.49
225.742.18
235.632.16
238.151.27
238.162.08
238.171.27
238.482.37
248.081.814
259.441.77
263.692.27
273.192.017
  1. 4.85 km SW of Guánica, Puerto Rico09-18 13:19
  2. 3.45 km W of Guánica, Puerto Rico09-18 17:20
  3. 3.15 km SW of Guánica, Puerto Rico09-19 05:06
  4. 3.15 km W of Guánica, Puerto Rico09-19 05:31
  5. 3.07 km SSE of Ponce, Puerto Rico09-20 07:53
  6. 3.05 km WSW of Guánica, Puerto Rico09-18 19:28
  7. 3.04 km SW of Guánica, Puerto Rico09-19 04:49
  8. 3.07 km SSE of Ponce, Puerto Rico09-19 07:01
  9. 3.05 km WSW of Guánica, Puerto Rico09-20 20:32
  10. 2.95 km SW of Guánica, Puerto Rico09-18 13:35
  11. 2.84 km WSW of Guánica, Puerto Rico09-18 18:23
  12. 2.8Near Guánica, Puerto Rico09-19 16:31
  13. 2.75 km W of Guánica, Puerto Rico09-18 19:24
  14. 2.76 km WSW of Guánica, Puerto Rico09-18 16:57
  15. 2.67 km SW of Guánica, Puerto Rico09-24 21:21
  16. 2.63 km SW of Guánica, Puerto Rico09-18 14:08
  17. 2.65 km SW of Guánica, Puerto Rico09-19 22:46
  18. 2.65 km WSW of Guánica, Puerto Rico09-18 22:28
  19. 2.64 km W of Guánica, Puerto Rico09-18 16:57
  20. 2.5Near Guánica, Puerto Rico09-18 21:41
  21. 2.5Near Guánica, Puerto Rico09-18 14:13
  22. 2.55 km SSW of Guánica, Puerto Rico09-18 18:24
  23. 2.54 km W of Guánica, Puerto Rico09-20 00:13
  24. 2.54 km WNW of Guánica, Puerto Rico09-18 13:22
  25. 2.55 km SW of Guánica, Puerto Rico09-23 06:15

Did you feel it?

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Reports on SeismoAtlas

No reports yet.

Event id pr71532008. First recorded here 28 Sept 2026, 17:32:11 UTC. Solutions: USGS · PR (usgs:pr71532008). Cite as: SeismoAtlas, “M3.0 earthquake 3 km SW of Guayanilla, Puerto Rico”, https://seismoatlas.com/earthquake/pr71532008-m3-0-earthquake-3-km-sw-of-guayanilla-puerto-rico, data from USGS.

JSON: /api/v1/events/pr71532008. SeismoAtlas is not an official warning service.