66 km NE of Cruz Bay, U.S. Virgin Islands

2016-08-21 23:08 UTC · 37 km deep · released about 120 lb of TNT

Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.

When: 2016-08-21 23:08 UTC
Magnitude: M 2.4 (Md)
Depth: 37 km below the surface
Felt: no reports yet
Nearest: Culebra Municipio, 113 km WSW
Status: Reviewed by a seismologist

USGS · last changed by USGS 3689 days ago · we first saw it 3689 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 120 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.

Mineral, Virginia 2011 M 5.8 130,000× the energy of this one
Magna, Utah 2020 M 5.7 89,000× the energy of this one
Around the size people start to feel M 3.0 7.9× the energy of this one
This earthquake M 2.4 about 120 lb of TNT

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.

Where

Map loads when it scrolls into view

Epicentre 18.7362, -64.3291. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Culebra Municipio, PR	113 km (70 mi)	ENE of here	earthquakes near Culebra Municipio
Vieques Municipio, PR	135 km (84 mi)	ENE of here	earthquakes near Vieques Municipio

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

25 earthquakes have been recorded within 50 km since this one.

3.1 59 km N of Cruz Bay, U.S. Virgin Islands 04:15 UTC
2.2 74 km NNE of Cruz Bay, U.S. Virgin Islands 14:51 UTC
2.2 63 km NE of Cruz Bay, U.S. Virgin Islands 12:17 UTC
2.3 110 km NE of Cruz Bay, U.S. Virgin Islands 05:51 UTC
2.7 106 km NE of Cruz Bay, U.S. Virgin Islands 05:49 UTC
2.1 69 km NE of Cruz Bay, U.S. Virgin Islands 22:46 UTC
3.0 21 km ENE of Cruz Bay, U.S. Virgin Islands 22:21 UTC
2.7 30 km N of Cruz Bay, U.S. Virgin Islands 04:41 UTC
2.3 31 km N of Cruz Bay, U.S. Virgin Islands 11:12 UTC
2.3 37 km NE of Cruz Bay, U.S. Virgin Islands 08:18 UTC
2.1 70 km NE of Cruz Bay, U.S. Virgin Islands 06:00 UTC
1.9 42 km NNE of Cruz Bay, U.S. Virgin Islands 04:41 UTC
1.9 79 km ENE of Cruz Bay, U.S. Virgin Islands 15:13 UTC
2.1 81 km ENE of Cruz Bay, U.S. Virgin Islands 11:59 UTC
3.5 77 km NNE of Cruz Bay, U.S. Virgin Islands 04:01 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 20:15 UTC. 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.