QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7md

Earthquake near Bufalo, PR

No earthquake was likely felt in Bufalo in the 24 hours to 12:12 pm AST (16:12 UTC). The last one was M 2.9, 15 km (9 mi) NNW, at 2:05 am AST on 13 October 2026, estimated intensity II (weak) in town. Every earthquake near Bufalo

This page: a magnitude 2.7 earthquake was recorded 2 km (1 mi) northwest of Bufalo, PR, at 3:30 am AST on 28 March 2019 (07:30 UTC), 125 km deep.

USGS: 2 km NW of Bufalo, Puerto Rico

55 km (34 mi) W of San Juan, PR · 16 km (10 mi) E of Arecibo, PR

3:30 am AST, Mar 28, 2019 · · 125 km deep · released about 390 lb of TNT

Every earthquake near Bufalo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Barceloneta Municipio 5 kmFlorida Municipio 8 kmArecibo Municipio 9 kmManatí Municipio 10 kmCiales Municipio 17 kmVega Baja Municipio 20 kmMorovis Municipio 22 kmUtuado Municipio 22 kmHatillo Municipio 22 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
3:30 am AST on 28 March 2019 ()
Where
2 km (1 mi) northwest of Bufalo, PR · earthquakes near Bufalo
Magnitude
M 2.7 (md)
Depth
125 km below the surface
Felt
no reports yet
Nearest
Barceloneta Municipio, 5 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2785 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 Bufalo, 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: Sabana Hoyos, Garrochales, Imbery, La Alianza, Animas, Barceloneta.

How big was it?

This earthquake released about 390 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 39,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 28,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.5× the energy of this one
  4. This earthquake M 2.7 about 390 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 310 times the energy of this one.

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

  1. 5.8 12 km N of Garrochales, Puerto Rico · 14 km N of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 27 km ENE 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 18.4346, -66.5865. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 5 km (3 mi) NE earthquakes near Barceloneta Municipio
Florida Municipio, PR 8 km (5 mi) SSE earthquakes near Florida Municipio
Arecibo Municipio, PR 9 km (6 mi) W earthquakes near Arecibo Municipio
Manatí Municipio, PR 10 km (6 mi) E earthquakes near Manatí Municipio
Ciales Municipio, PR 17 km (11 mi) SSE earthquakes near Ciales Municipio
Vega Baja Municipio, PR 20 km (12 mi) E earthquakes near Vega Baja Municipio

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

Aftershocks so far

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

  1. 1.6 3 km SSE of Adjuntas, Puerto Rico
  2. 1.6 3 km WNW of Santo Domingo, Puerto Rico
  3. 1.8 5 km SSE of Adjuntas, Puerto Rico
  4. 1.8 5 km S of Adjuntas, Puerto Rico
  5. 2.1 5 km NNE of Dorado, Puerto Rico
  6. 1.9 13 km N of Levittown, Puerto Rico
  7. 2.5 1 km ESE of Toa Baja, Puerto Rico
  8. 2.2 Puerto Rico region
  9. 1.9 6 km ESE of Maricao, Puerto Rico
  10. 2.2 11 km NNE of Arecibo, Puerto Rico
  11. 1.7 6 km ESE of Jayuya, Puerto Rico
  12. 1.8 8 km NNW of Brenas, Puerto Rico
  13. 1.5 1 km NNW of Animas, Puerto Rico
  14. 1.9 2 km N of Animas, Puerto Rico
  15. 2.9 37 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.