QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Guaynabo, PR

No earthquake was likely felt in Guaynabo in the 24 hours to 12:49 pm AST (16:49 UTC). The last one was M 4.1, 93 km (58 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 Guaynabo

This page: a magnitude 2.9 earthquake was recorded 2 km (1 mi) northeast of Guaynabo, PR, at 11:45 pm AST on 27 October 2019 (03:45 UTC), 104 km deep.

USGS: 2 km NE of Guaynabo, Puerto Rico

in San Juan, PR

11:45 pm AST, Oct 27, 2019 · · 104 km deep · released about 650 lb of TNT

Every earthquake near Guaynabo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guaynabo Municipio 4 kmSan Juan Municipio 6 kmBayamón Municipio 8 kmCataño Municipio 10 kmTrujillo Alto Municipio 11 kmAguas Buenas Municipio 13 kmCarolina Municipio 14 kmToa Baja Municipio 14 kmToa Alta Municipio 16 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
11:45 pm AST on 27 October 2019 ()
Where
2 km (1 mi) northeast of Guaynabo, PR · earthquakes near Guaynabo
Magnitude
M 2.9 (md)
Depth
104 km below the surface
Felt
no reports yet
Nearest
Guaynabo Municipio, 4 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2571 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 Guaynabo, 2 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, Bayamón, Cataño, Trujillo Alto, San Juan, Sabana Seca.

How big was it?

This earthquake released about 650 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 23,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 16,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.5× the energy of this one
  4. This earthquake M 2.9 about 650 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 4.6 on 2019-03-12 — about 370 times the energy of this one.

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 · 13 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 18.3718, -66.0961. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guaynabo Municipio, PR 4 km (2 mi) SSW earthquakes near Guaynabo Municipio
San Juan Municipio, PR 6 km (4 mi) NNE earthquakes near San Juan Municipio
Bayamón Municipio, PR 8 km (5 mi) WSW earthquakes near Bayamón Municipio
Cataño Municipio, PR 10 km (6 mi) NW earthquakes near Cataño Municipio
Trujillo Alto Municipio, PR 11 km (7 mi) ESE earthquakes near Trujillo Alto Municipio
Aguas Buenas Municipio, PR 13 km (8 mi) SSW earthquakes near Aguas Buenas Municipio

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

Aftershocks so far

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

  1. 2.3 2 km SW of Vázquez, Puerto Rico
  2. 2.5 1 km SW of Bairoa, Puerto Rico
  3. 2.0 2 km WSW of Vázquez, Puerto Rico
  4. 3.1 0 km ESE of Río Lajas, Puerto Rico
  5. 2.6 17 km N of Brenas, Puerto Rico
  6. 3.2 25 km N of Loíza, Puerto Rico
  7. 2.7 12 km NNE of Dorado, Puerto Rico
  8. 1.7 4 km SSE of Arroyo, Puerto Rico
  9. 2.4 1 km WSW of Coco, Puerto Rico
  10. 2.3 3 km NNE of La Plena, Puerto Rico
  11. 3.0 2 km NNW of Sabana, Puerto Rico
  12. 2.7 3 km N of Vega Baja, Puerto Rico
  13. 2.2 2 km NNE of Emajagua, Puerto Rico
  14. 2.8 14 km NNW of San Juan, Puerto Rico
  15. 2.4 34 km N of San Juan, 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.