QuakeIndex

Earthquake · reviewed by a seismologist

M 2.8md

Earthquake near Isabel Segunda, PR

No earthquake was likely felt in Isabel Segunda in the 24 hours to 10:12 am AST (14:12 UTC). The last one was M 2.9, 26 km (16 mi) SSE, at 12:08 pm AST on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Isabel Segunda

This page: a magnitude 2.8 earthquake was recorded 19 km (12 mi) south-southeast of Isabel Segunda, PR, at 9:00 pm AST on 4 March 2023 (01:00 UTC), 14 km deep.

USGS: Puerto Rico region

85 km (53 mi) ESE of San Juan, PR

9:00 pm AST, Mar 4, 2023 · · 14 km deep · released about 510 lb of TNT

Every earthquake near Isabel Segunda Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Vieques Municipio 16 kmCulebra Municipio 38 kmCeiba Municipio 39 kmNaguabo Municipio 45 kmHumacao Municipio 45 kmFajardo Municipio 49 kmYabucoa Municipio 51 kmMaunabo Municipio 54 kmLuquillo Municipio 54 km
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
9:00 pm AST on 4 March 2023 ()
Where
19 km (12 mi) south-southeast of Isabel Segunda, PR · earthquakes near Isabel Segunda
Magnitude
M 2.8 (md)
Depth
14 km below the surface
Felt
no reports yet
Nearest
Vieques Municipio, 16 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1348 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 24 km (15 mi) from the epicentre. In Isabel Segunda, 19 km away, the estimate is intensity II (weak). 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.

Likely felt in: Esperanza 15 km, intensity II · Isabel Segunda 19 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 510 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 30,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 21,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.9× the energy of this one
  4. This earthquake M 2.8 about 510 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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.8 on 2021-10-08 — about 930 times the energy of this one.

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 17.9888, -65.3855. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Vieques Municipio, PR 16 km (10 mi) NNW earthquakes near Vieques Municipio
Culebra Municipio, PR 38 km (24 mi) NNE earthquakes near Culebra Municipio
Ceiba Municipio, PR 39 km (24 mi) NW earthquakes near Ceiba Municipio
Naguabo Municipio, PR 45 km (28 mi) NW earthquakes near Naguabo Municipio
Humacao Municipio, PR 45 km (28 mi) WNW earthquakes near Humacao Municipio
Fajardo Municipio, PR 49 km (31 mi) NNW earthquakes near Fajardo Municipio

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

Aftershocks so far

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

  1. 3.4 29 km SSW of Esperanza, Puerto Rico
  2. 3.6 4 km SSW of Bajandas, Puerto Rico
  3. 2.9 19 km ENE of Fajardo, Puerto Rico
  4. 3.1 13 km ESE of El Negro, Puerto Rico
  5. 2.9 8 km SE of Esperanza, Puerto Rico
  6. 2.8 5 km S of Punta Santiago, Puerto Rico
  7. 2.9 31 km SSW of Esperanza, Puerto Rico
  8. 3.4 23 km SSW of Charlotte Amalie, U.S. Virgin Islands
  9. 2.4 30 km SE of Emajagua, Puerto Rico
  10. 3.7 26 km SSW of Esperanza, Puerto Rico
  11. 3.3 14 km SSE of Esperanza, Puerto Rico
  12. 3.1 15 km SE of Esperanza, Puerto Rico
  13. 3.0 20 km SE of Emajagua, Puerto Rico
  14. 3.2 22 km SSE of Esperanza, Puerto Rico
  15. 3.5 9 km ENE of Luis M. Cintron, Puerto Rico

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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.