M3.4 earthquake 46 km NNW of Road Town, British Virgin Islands
A magnitude 3.4 earthquake struck 46 km NNW of Road Town, British Virgin Islands at 04:00 local time (08:00 UTC) on 21 Sept 2026, at a depth of 85 km, according to USGS.
Data: USGS · updated 2026-09-21 09:39 UTC · reviewed
- Magnitude
- 3.4minor
duration magnitude (md) - Depth
- 85.5 km
- Status
- Reviewed
- Origin time
- 2026-09-21 08:00:55 UTC
- Local: 21 Sept 2026, 04:00:55 (America/Tortola)
- Epicentre
- 18.810° N, 64.792° 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 |
|---|---|---|
| Road TownBritish Virgin Islands · pop. 8,449 | 46 km | INot felt |
| TutuSaint Thomas Island, U.S. Virgin Islands · pop. 5,519 | 53 km | INot felt |
| Charlotte AmalieSaint Thomas Island, U.S. Virgin Islands · pop. 20,000 | 54 km | INot felt |
| FajardoPuerto Rico · pop. 32,124 | 105 km | INot felt |
| Saint CroixSaint Croix Island, U.S. Virgin Islands · pop. 50,601 | 120 km | INot felt |
| HumacaoPuerto Rico · pop. 20,387 | 132 km | INot felt |
| San JuanPuerto Rico · pop. 418,140 | 144 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.
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 | 3.4 md | 85.5 km | 18.81° N, 64.79° 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 1.8 t 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 85 km this was a intermediate-depth earthquake, which spreads shaking over a wider area but less intensely.
M3.4 releases about 31× the energy of M2.4, and its waves are about 9.8× taller on a seismogram. Energy: 1.8 t of TNT vs 60 kg of TNT.
Each square is the energy of one M2.4. Energy from log₁₀E = 1.5M + 4.8.
Aftershocks and nearby activity
3 later earthquakes within 30 km; the largest was M2.9 7 days ago. Aftershock rates usually fall off roughly in proportion to 1/time.
Mainshock M3.4
3 later earthquakes nearby. Aftershock rates typically fall off roughly as 1/time (Omori's law).
| Time after mainshock (hours) | Magnitude | Depth (km) |
|---|---|---|
| 2.24 | 2.9 | 11 |
| 38.01 | 2.6 | 15 |
| 179.32 | 2.9 | 24 |
Did you feel it?
Reports from people help show where shaking was strong. They are anonymous and shown here in aggregate.
Reports on SeismoAtlas
No reports yet.
Event id pr71533853. First recorded here 28 Sept 2026, 17:32:10 UTC. Solutions: USGS · PR (usgs:pr71533853). Cite as: SeismoAtlas, “M3.4 earthquake 46 km NNW of Road Town, British Virgin Islands”, https://seismoatlas.com/earthquake/pr71533853-m3-4-earthquake-46-km-nnw-of-road-town-british-virgin-islands, data from USGS.
JSON: /api/v1/events/pr71533853. SeismoAtlas is not an official warning service.