QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 6:06 pm AST (22:06 UTC). The last one was M 3.4, 49 km (31 mi) NW, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Arecibo

This page: a magnitude 3.1 earthquake was recorded 36 km (23 mi) north-northeast of Arecibo, PR, at 1:24 pm AST on 26 August 2026 (17:24 UTC), 51 km deep. 1 person has reported feeling it to USGS.

USGS: 36 km NNE of Arecibo, Puerto Rico

73 km (46 mi) NW of San Juan, PR · 39 km (24 mi) NNE of Arecibo, PR

1:24 pm AST, Aug 26, 2026 · · 51 km deep · released about 1,400 lb of TNT

10 km30 km60 km120 km N Barceloneta Municipio 36 kmArecibo Municipio 40 kmManatí Municipio 41 kmHatillo Municipio 43 kmVega Baja Municipio 45 kmCamuy Municipio 46 kmFlorida Municipio 47 kmQuebradillas Municipio 48 kmVega Alta Municipio 50 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
1:24 pm AST on 26 August 2026 ()
Where
36 km (23 mi) north-northeast of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 3.1 (md)
Depth
51 km below the surface
Felt
1 report · strongest reported intensity I
Nearest
Barceloneta Municipio, 36 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 77 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 Arecibo, 36 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.

How big was it?

This earthquake released about 1,400 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 240,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,700× the energy of this one
  4. This earthquake M 3.1 about 1,400 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.5× 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 2017-08-18 — about 340 times the energy of this one.

Before 2016, the USGS record lists 11 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.4 61 km N of Hatillo, Puerto Rico · 34 km NW of this epicentre
  2. 5.9 78 km N of Arecibo, Puerto Rico · 43 km N of this epicentre
  3. 5.8 12 km N of Garrochales, Puerto Rico · 26 km SSE of this epicentre
  4. 5.7 78 km N of Tierras Nuevas Poniente, Puerto Rico · 42 km N of this epicentre
  5. 5.6 57 km N of Isabela, Puerto Rico · 40 km NW 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 18.7900, -66.6293. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 36 km (23 mi) SSE earthquakes near Barceloneta Municipio
Arecibo Municipio, PR 40 km (25 mi) S earthquakes near Arecibo Municipio
Manatí Municipio, PR 41 km (25 mi) SSE earthquakes near Manatí Municipio
Hatillo Municipio, PR 43 km (27 mi) SSW earthquakes near Hatillo Municipio
Vega Baja Municipio, PR 45 km (28 mi) SSE earthquakes near Vega Baja Municipio
Camuy Municipio, PR 46 km (28 mi) SSW earthquakes near Camuy Municipio

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

Aftershocks so far

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

  1. 2.8 9 km NNW of Garrochales, Puerto Rico
  2. 3.0 52 km N of San Juan, Puerto Rico
  3. 2.5 25 km N of Tierras Nuevas Poniente, Puerto Rico
  4. 2.8 18 km NNE of Tierras Nuevas Poniente, Puerto Rico
  5. 3.4 31 km N of Isabela, Puerto Rico
  6. 3.3 53 km N of Brenas, Puerto Rico
  7. 3.1 22 km NNE of Brenas, Puerto Rico
  8. 3.1 48 km N of Hatillo, Puerto Rico
  9. 2.8 7 km NNE of Isabela, Puerto Rico
  10. 2.7 6 km NE of Isabela, Puerto Rico
  11. 2.9 10 km N of Animas, Puerto Rico
  12. 3.1 68 km N of Tierras Nuevas Poniente, Puerto Rico
  13. 2.5 17 km NNE of Isabela, Puerto Rico
  14. 2.8 16 km NNE of Arecibo, Puerto Rico
  15. 3.1 4 km NNE of Animas, 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.