QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5md

Earthquake near Esperanza, PR

No earthquake was likely felt in Esperanza in the 24 hours to 10:54 pm AST (02:54 UTC). The last one was M 2.9, 23 km (14 mi) SE, at 12:08 pm AST on 29 October 2026, estimated intensity II (weak) in town. Every earthquake near Esperanza

This page: a magnitude 3.5 earthquake was recorded 13 km (8 mi) southeast of Esperanza, PR, at 4:22 pm AST on 8 October 2021 (20:22 UTC), 12 km deep. 4 people have reported feeling it to USGS.

USGS: 13 km SE of Esperanza, Puerto Rico

84 km (52 mi) ESE of San Juan, PR

4:22 pm AST, Oct 8, 2021 · · 12 km deep · released about 3.2 tons of TNT

Every earthquake near Esperanza Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Vieques Municipio 13 kmCulebra Municipio 35 kmCeiba Municipio 37 kmNaguabo Municipio 43 kmHumacao Municipio 45 kmFajardo Municipio 47 kmYabucoa Municipio 51 kmLuquillo Municipio 52 kmMaunabo 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
4:22 pm AST on 8 October 2021 ()
Where
13 km (8 mi) southeast of Esperanza, PR · earthquakes near Esperanza
Magnitude
M 3.5 (md)
Depth
12 km below the surface
Felt
4 reports · strongest reported intensity II
Nearest
Vieques Municipio, 13 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1789 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 65 km (40 mi) from the epicentre. In Esperanza, 13 km away, the estimate is intensity III (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 13 km, intensity III · Isabel Segunda 16 km, intensity III · Culebra 33 km, intensity II · Aguas Claras 39 km, intensity II · Fajardo 45 km, intensity II · Humacao 49 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 3.2 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 53,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 1,700× the energy of this one
  4. This earthquake M 3.5 about 3.2 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 6.7× 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 2021-10-08 — about 75 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 18.0158, -65.3815. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Vieques Municipio, PR 13 km (8 mi) NNW earthquakes near Vieques Municipio
Culebra Municipio, PR 35 km (22 mi) NNE earthquakes near Culebra Municipio
Ceiba Municipio, PR 37 km (23 mi) NW earthquakes near Ceiba Municipio
Naguabo Municipio, PR 43 km (27 mi) WNW earthquakes near Naguabo Municipio
Humacao Municipio, PR 45 km (28 mi) WNW earthquakes near Humacao Municipio
Fajardo Municipio, PR 47 km (29 mi) NNW earthquakes near Fajardo Municipio

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

Aftershocks so far

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

  1. 2.9 13 km S of Esperanza, Puerto Rico
  2. 2.4 15 km S of Esperanza, Puerto Rico
  3. 2.3 6 km S of Esperanza, Puerto Rico
  4. 2.6 2 km NW of Punta Santiago, Puerto Rico
  5. 3.0 36 km SSW of Charlotte Amalie, U.S. Virgin Islands
  6. 2.7 2 km NW of Punta Santiago, Puerto Rico
  7. 3.5 18 km S of Esperanza, Puerto Rico
  8. 2.3 2 km NNW of Punta Santiago, Puerto Rico
  9. 3.3 36 km SSW of Charlotte Amalie, U.S. Virgin Islands
  10. 2.9 33 km SSW of Esperanza, Puerto Rico
  11. 2.3 10 km SW of Esperanza, Puerto Rico
  12. 3.6 5 km E of Candelero Arriba, Puerto Rico
  13. 3.1 9 km SE of Esperanza, Puerto Rico
  14. 3.0 10 km ENE of Luis M. Cintron, Puerto Rico
  15. 2.9 25 km SE of Emajagua, 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.