QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

Earthquake near Mayagüez, PR

No earthquake was likely felt in Mayagüez in the 24 hours to 7:55 pm AST (23:55 UTC). The last one was M 2.9, 25 km (15 mi) SSE, at 3:17 am AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Mayagüez

This page: a magnitude 3.4 earthquake was recorded 50 km (31 mi) northwest of Mayagüez, PR, at 7:29 pm AST on 31 May 2026 (23:29 UTC), 9.8 km deep.

USGS: 31 km NW of Rincón, Puerto Rico

50 km (31 mi) NW of Mayagüez, PR · 141 km (87 mi) W of Bayamón, PR

7:29 pm AST, May 31, 2026 · · 9.8 km deep · released about 2.1 tons of TNT

Every earthquake near Mayagüez Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Rincón Municipio 31 kmAguada Municipio 35 kmAguadilla Municipio 37 kmAñasco Municipio 45 kmMoca Municipio 46 kmIsabela Municipio 50 kmHormigueros Municipio 57 kmSan Sebastián Municipio 58 kmQuebradillas Municipio 60 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
7:29 pm AST on 31 May 2026 ()
Where
50 km (31 mi) northwest of Mayagüez, PR · earthquakes near Mayagüez
Magnitude
M 3.4 (md)
Depth
9.8 km below the surface
Felt
no reports yet
Nearest
Rincón Municipio, 31 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 92 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 59 km (37 mi) from the epicentre. In Mayagüez, 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.

Likely felt in: Rincón 31 km, intensity II · Aguada 35 km, intensity II · Aguadilla 37 km, intensity II · Rafael Hernandez 44 km, intensity II · Isabela 49 km, intensity II · Mayagüez 50 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 2.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 80,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 3,600× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,500× the energy of this one
  4. This earthquake M 3.4 about 2.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4.4× 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 4.4 on 2017-10-01 — about 29 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 24 km NNW of San Antonio, Puerto Rico · 39 km NE of this epicentre
  2. 6.4 32 km NW of Aguadilla, Puerto Rico · 17 km NE of this epicentre
  3. 6.3 6 km WNW of Aguadilla, Puerto Rico · 30 km ESE of this epicentre
  4. 6.3 58 km E of Punta Cana, Dominican Republic · 39 km W of this epicentre
  5. 6.1 15 km WNW of San Antonio, Puerto Rico · 28 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 18.5020, -67.4915. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Rincón Municipio, PR 31 km (19 mi) SE earthquakes near Rincón Municipio
Aguada Municipio, PR 35 km (22 mi) ESE earthquakes near Aguada Municipio
Aguadilla Municipio, PR 37 km (23 mi) E earthquakes near Aguadilla Municipio
Añasco Municipio, PR 45 km (28 mi) ESE earthquakes near Añasco Municipio
Moca Municipio, PR 46 km (28 mi) ESE earthquakes near Moca Municipio
Isabela Municipio, PR 50 km (31 mi) E earthquakes near Isabela Municipio

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

Aftershocks so far

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

  1. 3.2 16 km WNW of Puerto Real, Puerto Rico
  2. 3.2 8 km SW of Stella, Puerto Rico
  3. 3.1 5 km W of Mayagüez, Puerto Rico
  4. 3.6 45 km WSW of Stella, Puerto Rico
  5. 2.5 19 km WSW of Stella, Puerto Rico
  6. 2.8 17 km NW of San Antonio, Puerto Rico
  7. 2.4 2 km NW of Mayagüez, Puerto Rico
  8. 2.8 42 km NW of San Antonio, Puerto Rico
  9. 2.6 25 km W of Puerto Real, Puerto Rico
  10. 2.8 36 km W of Rincón, Puerto Rico
  11. 2.5 14 km W of Puerto Real, Puerto Rico
  12. 3.3 60 km WSW of Stella, Puerto Rico
  13. 3.1 42 km NW of Aguadilla, Puerto Rico
  14. 3.2 62 km NW of San Antonio, Puerto Rico
  15. 3.1 72 km NW of San Antonio, 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.