Earthquake · reviewed by a seismologist
M 3.4md
102 km N of Cruz Bay, U.S. Virgin Islands
Yes. A magnitude 3.4 earthquake was recorded 102 km N of Cruz Bay, U.S. Virgin Islands, at 2:17 pm AST on 28 September 2019 (18:17 UTC), 59 km deep.
- When
- Magnitude
- M 3.4 (md)
- Depth
- 59 km below the surface
- Felt
- no reports yet
- Nearest
- Culebra Municipio, 120 km SSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2518 days ago
This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 7 km (4 mi) from the epicentre. Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.
How big was it?
This earthquake released about 2.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.
- Northridge, California 1994 M 6.7 80,000× the energy of this one
- Mineral, Virginia 2011 M 5.8 3,600× the energy of this one
- Magna, Utah 2020 M 5.7 2,500× the energy of this one
- This earthquake M 3.4 about 2.1 tons of TNT
- Around the size people start to feel M 3.0 this one released 4.4× more
Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.
For this area
The largest earthquake within 50 km since 2016 was M 4.8 on 2019-02-18 — about 110 times the energy of this one.
Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:
- 6.2 131 km NNE of Cruz Bay, U.S. Virgin Islands · 35 km NE of this epicentre
- 6.1 91 km N of Charlotte Amalie, U.S. Virgin Islands · 15 km SW of this epicentre
- 6.0 112 km N of Charlotte Amalie, U.S. Virgin Islands · 24 km WNW of this epicentre
- 5.9 68 km N of Cruz Bay, U.S. Virgin Islands · 35 km S of this epicentre
- 5.9 65 km NNE of Cruz Bay, U.S. Virgin Islands · 44 km SSE of this epicentre
Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.
Where
Epicentre 19.2591, -64.7301. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Culebra Municipio, PR | 120 km (75 mi) | SSW | earthquakes near Culebra Municipio |
| Fajardo Municipio, PR | 133 km (82 mi) | SW | earthquakes near Fajardo Municipio |
| Luquillo Municipio, PR | 143 km (89 mi) | SW | earthquakes near Luquillo Municipio |
| Ceiba Municipio, PR | 146 km (91 mi) | SW | earthquakes near Ceiba Municipio |
| Río Grande Municipio, PR | 149 km (93 mi) | SW | earthquakes near Río Grande Municipio |
| Naguabo Municipio, PR | 157 km (98 mi) | SW | earthquakes near Naguabo Municipio |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
46 earthquakes have been recorded within 50 km since this one.
- 3.4 Virgin Islands
- 2.9 84 km NNE of Cruz Bay, U.S. Virgin Islands
- 3.5 107 km NNE of Cruz Bay, U.S. Virgin Islands
- 3.3 126 km N of Cruz Bay, U.S. Virgin Islands
- 3.4 130 km NNE of Cruz Bay, U.S. Virgin Islands
- 3.6 137 km NNE of Cruz Bay, U.S. Virgin Islands
- 2.8 94 km N of Cruz Bay, U.S. Virgin Islands
- 2.9 141 km N of Cruz Bay, U.S. Virgin Islands
- 3.3 Puerto Rico region
- 3.3 70 km N of Charlotte Amalie, U.S. Virgin Islands
- 3.1 90 km N of Cruz Bay, U.S. Virgin Islands
- 3.7 106 km NNE of Cruz Bay, U.S. Virgin Islands
- 3.9 125 km N of Charlotte Amalie, U.S. Virgin Islands
- 3.3 80 km N of Cruz Bay, U.S. Virgin Islands
- 3.4 84 km N of Charlotte Amalie, U.S. Virgin Islands
Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.
On USGS
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.