QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

Earthquake near Carrizales, PR

No earthquake was likely felt in Carrizales in the 24 hours to 1:34 pm AST (17:34 UTC). The last one was M 3.4, 43 km (27 mi) NW, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Carrizales

This page: a magnitude 3.0 earthquake was recorded 15 km (10 mi) north-northeast of Carrizales, PR, at 12:30 am AST on 29 October 2021 (04:30 UTC), 13 km deep. 1 person has reported feeling it to USGS.

USGS: 15 km NNE of Carrizales, Puerto Rico

75 km (47 mi) WNW of San Juan, PR · 18 km (11 mi) N of Arecibo, PR

12:30 am AST, Oct 29, 2021 · · 13 km deep · released about 830 lb of TNT

Every earthquake near Carrizales Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hatillo Municipio 20 kmArecibo Municipio 21 kmCamuy Municipio 23 kmBarceloneta Municipio 25 kmQuebradillas Municipio 25 kmIsabela Municipio 32 kmManatí Municipio 32 kmFlorida Municipio 33 kmUtuado Municipio 38 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
12:30 am AST on 29 October 2021 ()
Where
15 km (10 mi) north-northeast of Carrizales, PR · earthquakes near Carrizales
Magnitude
M 3.0 (md)
Depth
13 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Hatillo Municipio, 20 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1556 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 32 km (20 mi) from the epicentre. In Carrizales, 15 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: Arecibo 16 km, intensity II · Hatillo 17 km, intensity II · Quebradillas 26 km, intensity II · Barceloneta 28 km, intensity II · Isabela 32 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 830 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 410,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 18,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 13,000× the energy of this one
  4. This earthquake M 3.0 about 830 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 since 2016 was M 4.4 on 2018-12-09 — about 140 times the energy of this one.

Before 2016, the USGS record lists 9 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 24 km NNW of San Antonio, Puerto Rico · 48 km WNW of this epicentre
  2. 6.4 61 km N of Hatillo, Puerto Rico · 48 km N of this epicentre
  3. 6.1 18 km NNW of San Antonio, Puerto Rico · 46 km W of this epicentre
  4. 5.8 12 km N of Garrochales, Puerto Rico · 20 km ESE of this epicentre
  5. 5.8 4 km E of Moca, Puerto Rico · 42 km SW 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 18.6138, -66.7428. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Hatillo Municipio, PR 20 km (12 mi) SSW earthquakes near Hatillo Municipio
Arecibo Municipio, PR 21 km (13 mi) SSE earthquakes near Arecibo Municipio
Camuy Municipio, PR 23 km (14 mi) SW earthquakes near Camuy Municipio
Barceloneta Municipio, PR 25 km (16 mi) SE earthquakes near Barceloneta Municipio
Quebradillas Municipio, PR 25 km (16 mi) SW earthquakes near Quebradillas Municipio
Isabela Municipio, PR 32 km (20 mi) WSW earthquakes near Isabela Municipio

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

Aftershocks so far

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

  1. 2.3 9 km N of Animas, Puerto Rico
  2. 3.1 28 km N of Arecibo, Puerto Rico
  3. 3.3 46 km N of Arecibo, Puerto Rico
  4. 3.0 4 km N of Animas, Puerto Rico
  5. 3.1 53 km N of Tierras Nuevas Poniente, Puerto Rico
  6. 3.3 1 km WNW of Morovis, Puerto Rico
  7. 2.6 23 km NNE of Isabela, Puerto Rico
  8. 2.1 18 km NNE of Carrizales, Puerto Rico
  9. 2.9 13 km N of Brenas, Puerto Rico
  10. 3.1 52 km N of Carrizales, Puerto Rico
  11. 3.0 42 km N of Tierras Nuevas Poniente, Puerto Rico
  12. 2.1 2 km ESE of Moca, Puerto Rico
  13. 3.4 28 km N of Arecibo, Puerto Rico
  14. 3.4 48 km N of Isabela, Puerto Rico
  15. 3.0 16 km N of Camuy, 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.