QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

Earthquake near Cataño, PR

No earthquake was likely felt in Cataño in the 24 hours to 11:23 pm AST (03:23 UTC). The last one was M 4.1, 99 km (61 mi) ESE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Cataño

This page: a magnitude 3.0 earthquake was recorded 6 km (4 mi) east-southeast of Cataño, PR, at 7:33 pm AST on 12 August 2021 (23:33 UTC), 118 km deep. 3 people have reported feeling it to USGS.

USGS: 5 km ESE of Cataño, Puerto Rico

in San Juan, PR

7:33 pm AST, Aug 12, 2021 · · 118 km deep · released about 1,100 lb of TNT

Every earthquake near Cataño Felt it? Tell USGS Check my area
10 km30 km60 km120 km N San Juan Municipio 1 kmCataño Municipio 9 kmGuaynabo Municipio 9 kmCarolina Municipio 11 kmTrujillo Alto Municipio 11 kmBayamón Municipio 13 kmToa Baja Municipio 14 kmLoíza Municipio 14 kmGurabo Municipio 19 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
7:33 pm AST on 12 August 2021 ()
Where
6 km (4 mi) east-southeast of Cataño, PR · earthquakes near Cataño
Magnitude
M 3.0 (md)
Depth
118 km below the surface
Felt
3 reports · strongest reported intensity II
Nearest
San Juan Municipio, 1 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1913 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 it was probably too small to be felt, even directly above it. In Cataño, 6 km away, the estimate is intensity I (not felt). 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.

Earthquakes near other towns within 30 km: Eleanor Roosevelt, San Juan, Guaynabo, Bayamón, Trujillo Alto, Sabana Seca.

How big was it?

This earthquake released about 1,100 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 6.7 300,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,400× the energy of this one
  4. This earthquake M 3.0 about 1,100 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 19 km SSW of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 30 km WNW 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 18.4166, -66.0701. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
San Juan Municipio, PR 1 km (0 mi) N earthquakes near San Juan Municipio
Cataño Municipio, PR 9 km (6 mi) WNW earthquakes near Cataño Municipio
Guaynabo Municipio, PR 9 km (6 mi) SSW earthquakes near Guaynabo Municipio
Carolina Municipio, PR 11 km (7 mi) ESE earthquakes near Carolina Municipio
Trujillo Alto Municipio, PR 11 km (7 mi) SE earthquakes near Trujillo Alto Municipio
Bayamón Municipio, PR 13 km (8 mi) SW earthquakes near Bayamón Municipio

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

Aftershocks so far

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

  1. 2.8 23 km NNE of Tierras Nuevas Poniente, Puerto Rico
  2. 2.8 8 km NW of Loíza, Puerto Rico
  3. 3.0 2 km N of Yaurel, Puerto Rico
  4. 2.8 0 km SW of Pastos, Puerto Rico
  5. 3.1 Puerto Rico region
  6. 3.4 13 km NNE of Tierras Nuevas Poniente, Puerto Rico
  7. 2.7 2 km N of Orocovis, Puerto Rico
  8. 3.1 3 km N of Olimpo, Puerto Rico
  9. 3.1 4 km NNW of Levittown, Puerto Rico
  10. 3.0 0 km W of Sumidero, Puerto Rico
  11. 2.4 3 km SSE of Pájaros, Puerto Rico
  12. 3.3 1 km ESE of Guaynabo, Puerto Rico
  13. 3.3 1 km WNW of Morovis, Puerto Rico
  14. 2.1 4 km WNW of Coamo, Puerto Rico
  15. 2.9 13 km N of Brenas, 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.