M3.0 earthquake 5 km WSW of Guánica, Puerto Rico
A magnitude 3.0 earthquake struck 5 km WSW of Guánica, Puerto Rico at 16:32 local time (20:32 UTC) on 20 Sept 2026, at a depth of 8 km, according to USGS.
1 reports to USGS “Did You Feel It?”
Data: USGS · updated 2026-09-20 20:54 UTC · reviewed
- Magnitude
- 3.0micro
duration magnitude (md) - Depth
- 8 km
- Status
- Reviewed
- Origin time
- 2026-09-20 20:32:36 UTC
- Local: 20 Sept 2026, 16:32:36 (America/Puerto Rico)
- Epicentre
- 17.957° N, 66.951° 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
| Place | Distance | Est. shaking |
|---|---|---|
| GuánicaPuerto Rico · pop. 9,224 | 5 km | IIIWeak |
| YaucoPuerto Rico · pop. 20,295 | 13 km | IIWeak |
| MayagüezPuerto Rico · pop. 73,077 | 34 km | INot felt |
| PoncePuerto Rico · pop. 137,491 | 36 km | INot felt |
| AreciboPuerto Rico · pop. 87,754 | 62 km | INot felt |
| San JuanPuerto Rico · pop. 418,140 | 106 km | INot felt |
| Santo Domingo EsteSanto Domingo Province, Dominican Republic · pop. 700,000 | 312 km | INot felt |
| Santo DomingoNacional, Dominican Republic · pop. 2,201,941 | 316 km | INot 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 13 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.
| Agency | Magnitude | Depth | Epicentre | Time offset | Status |
|---|---|---|---|---|---|
| USGS · PRheadlinePuerto Rico Seismic Network via U.S. Geological Survey | 3.0 md | 8 km | 17.96° N, 66.95° W | – | Reviewed |
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How big was it?
Usually not felt. Recorded by nearby seismometers; thousands occur worldwide every day.
It released roughly the energy of 401 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 8 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 M2.0, and its waves are about 8.9× taller on a seismogram. Energy: 401 kg of TNT vs 15 kg of TNT.
Each square is the energy of one M2.0. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
35 later earthquakes within 30 km; the largest was M2.6 4 days ago. 29 in the 7 days before. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M3.0
35 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 3.10 | 2.5 | 7 |
| 27.97 | 2.1 | 11 |
| 28.51 | 2.2 | 15 |
| 32.55 | 2.0 | 17 |
| 41.21 | 1.8 | 11 |
| 42.19 | 2.1 | 7 |
| 43.22 | 1.8 | 7 |
| 46.80 | 2.2 | 8 |
| 52.52 | 2.1 | 8 |
| 54.69 | 2.2 | 7 |
| 56.39 | 2.1 | 17 |
| 57.72 | 2.5 | 7 |
| 68.48 | 1.7 | 8 |
| 69.73 | 2.3 | 14 |
| 72.31 | 2.1 | 8 |
| 72.39 | 2.3 | 7 |
| 74.73 | 2.0 | 8 |
| 78.98 | 1.9 | 9 |
| 94.72 | 2.1 | 12 |
| 96.82 | 2.6 | 8 |
| 97.72 | 2.4 | 6 |
| 99.76 | 2.3 | 7 |
| 109.74 | 2.0 | 9 |
| 112.47 | 2.1 | 7 |
| 135.96 | 2.4 | 9 |
| 141.14 | 2.1 | 8 |
| 151.03 | 2.1 | 6 |
| 153.55 | 1.2 | 7 |
| 153.56 | 2.0 | 8 |
| 153.57 | 1.2 | 7 |
| 153.88 | 2.3 | 7 |
| 174.84 | 1.7 | 7 |
| 179.09 | 2.2 | 7 |
| 188.59 | 2.0 | 17 |
| 194.78 | 2.3 | 7 |
- 2.67 km SW of Guánica, Puerto Rico09-24 21:21
- 2.55 km SW of Guánica, Puerto Rico09-23 06:15
- 2.54 km W of Guánica, Puerto Rico09-20 23:38
- 2.45 km WSW of Guánica, Puerto Rico09-24 22:16
- 2.44 km SE of Guánica, Puerto Rico09-26 12:30
- 2.3Near Guayanilla, Puerto Rico09-23 18:16
- 2.34 km W of Guánica, Puerto Rico09-25 00:18
- 2.34 km SW of Guánica, Puerto Rico09-23 20:55
- 2.35 km SW of Guánica, Puerto Rico09-27 06:25
- 2.35 km SW of Guánica, Puerto Rico09-28 23:19
- 2.23 km SW of Guánica, Puerto Rico09-22 19:20
- 2.24 km SW of Guayanilla, Puerto Rico09-22 01:03
- 2.24 km SW of Guánica, Puerto Rico09-23 03:13
- 2.2Near Guánica, Puerto Rico09-28 07:37
- 2.15 km W of Guánica, Puerto Rico09-22 14:44
- 2.13 km ESE of Yauco, Puerto Rico09-23 01:03
- 2.15 km ESE of Guayanilla, Puerto Rico09-23 04:55
- 2.15 km NNW of Guánica, Puerto Rico09-23 20:51
- 2.14 km WSW of Guánica, Puerto Rico09-25 13:01
- 2.17 km SSW of Guayanilla, Puerto Rico09-22 00:30
- 2.13 km W of Guánica, Puerto Rico09-26 17:40
- 2.16 km S of Yauco, Puerto Rico09-24 19:16
- 2.14 km WNW of Guánica, Puerto Rico09-27 03:34
- 2.05 km S of Yauco, Puerto Rico09-22 05:05
- 2.08 km SSW of Guánica, Puerto Rico09-27 06:06
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Event id pr71533593. First recorded here 28 Sept 2026, 17:32:10 UTC. Solutions: USGS · PR (usgs:pr71533593). Cite as: SeismoAtlas, “M3.0 earthquake 5 km WSW of Guánica, Puerto Rico”, https://seismoatlas.com/earthquake/pr71533593-m3-0-earthquake-5-km-wsw-of-guanica-puerto-rico, data from USGS.
JSON: /api/v1/events/pr71533593. SeismoAtlas is not an official warning service.