QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3md

Earthquake near Arecibo, PR

No earthquake was likely felt in Arecibo in the 24 hours to 11:26 am AST (15:26 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 3.3 earthquake was recorded 50 km (31 mi) north of Arecibo, PR, at 10:30 am AST on 17 September 2023 (14:30 UTC), 20 km deep.

USGS: 47 km N of Hatillo, Puerto Rico

96 km (59 mi) NW of San Juan, PR · 51 km (32 mi) N of Arecibo, PR

10:30 am AST, Sep 17, 2023 · · 20 km deep · released about 1.3 tons of TNT

Every earthquake near Arecibo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Quebradillas Municipio 51 kmCamuy Municipio 52 kmHatillo Municipio 52 kmIsabela Municipio 53 kmArecibo Municipio 55 kmBarceloneta Municipio 55 kmAguadilla Municipio 60 kmManatí Municipio 61 kmFlorida Municipio 65 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
10:30 am AST on 17 September 2023 ()
Where
50 km (31 mi) north of Arecibo, PR · earthquakes near Arecibo
Magnitude
M 3.3 (md)
Depth
20 km below the surface
Felt
no reports yet
Nearest
Quebradillas Municipio, 51 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1151 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 47 km (29 mi) from the epicentre. In Arecibo, 50 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 1.3 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 130,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 6,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,300× the energy of this one
  4. This earthquake M 3.3 about 1.3 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.6× 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 5.1 on 2019-09-24 — about 470 times the energy of this one.

Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 34 km W of this epicentre
  2. 7.1 24 km NNW of San Antonio, Puerto Rico · 47 km WSW of this epicentre
  3. 6.4 61 km N of Hatillo, Puerto Rico · 15 km N of this epicentre
  4. 6.0 81 km N of Isabela, Puerto Rico · 38 km NNW of this epicentre
  5. 5.9 78 km N of Arecibo, Puerto Rico · 33 km NNE 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 18.9118, -66.7975. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Quebradillas Municipio, PR 51 km (32 mi) SSW earthquakes near Quebradillas Municipio
Camuy Municipio, PR 52 km (33 mi) S earthquakes near Camuy Municipio
Hatillo Municipio, PR 52 km (33 mi) S earthquakes near Hatillo Municipio
Isabela Municipio, PR 53 km (33 mi) SSW earthquakes near Isabela Municipio
Arecibo Municipio, PR 55 km (34 mi) SSE earthquakes near Arecibo Municipio
Barceloneta Municipio, PR 55 km (34 mi) SSE earthquakes near Barceloneta Municipio

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

Aftershocks so far

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

  1. 3.5 68 km N of Arecibo, Puerto Rico
  2. 3.2 84 km N of Isabela, Puerto Rico
  3. 3.0 12 km NNE of Isabela, Puerto Rico
  4. 3.2 74 km N of Tierras Nuevas Poniente, Puerto Rico
  5. 3.2 63 km N of Tierras Nuevas Poniente, Puerto Rico
  6. 3.7 73 km N of Tierras Nuevas Poniente, Puerto Rico
  7. 3.4 67 km N of Tierras Nuevas Poniente, Puerto Rico
  8. 3.3 71 km N of Tierras Nuevas Poniente, Puerto Rico
  9. 2.8 16 km N of Arecibo, Puerto Rico
  10. 3.4 71 km N of Isabela, Puerto Rico
  11. 3.0 49 km N of Brenas, Puerto Rico
  12. 3.0 21 km NNE of Isabela, Puerto Rico
  13. 3.6 71 km N of Tierras Nuevas Poniente, Puerto Rico
  14. 2.7 14 km NE of Arecibo, Puerto Rico
  15. 3.0 Puerto Rico region

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.