QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Arroyo, PR

No earthquake was likely felt in Arroyo in the 24 hours to 12:54 pm AST (16:54 UTC). The last one was M 3.3, 39 km (24 mi) WSW, at 8:40 am AST on 1 November 2026, estimated intensity II (weak) in town. Every earthquake near Arroyo

This page: a magnitude 2.9 earthquake was recorded in Arroyo, PR, at 5:38 am AST on 2 April 2020 (09:38 UTC), 2.0 km deep.

USGS: 1 km SW of Arroyo, Puerto Rico

49 km (31 mi) S of San Juan, PR · 30 km (19 mi) S of Caguas, PR

5:38 am AST, Apr 2, 2020 · · 2.0 km deep · released about 780 lb of TNT

Every earthquake near Arroyo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Arroyo Municipio 3 kmGuayama Municipio 7 kmPatillas Municipio 10 kmCayey Municipio 18 kmMaunabo Municipio 19 kmSalinas Municipio 20 kmSan Lorenzo Municipio 23 kmYabucoa Municipio 25 kmCidra Municipio 26 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
5:38 am AST on 2 April 2020 ()
Where
in Arroyo, PR · earthquakes near Arroyo
Magnitude
M 2.9 (md)
Depth
2.0 km below the surface
Felt
no reports yet
Nearest
Arroyo Municipio, 3 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2414 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 34 km (21 mi) from the epicentre. 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: Guayama 5 km, intensity III · Cayey 20 km, intensity II · Emajagua 20 km, intensity II · Jagual 24 km, intensity II · Sumidero 29 km, intensity II · Caguas 31 km, intensity II · Humacao 33 km, intensity II · Coamo 33 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 780 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 19,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 14,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.2× the energy of this one
  4. This earthquake M 2.9 about 780 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 2016-12-05 — about 310 times the energy of this one.

Before 2016, the USGS record lists one earthquake of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 34 km NNW 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 17.9601, -66.0693. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Arroyo Municipio, PR 3 km (2 mi) ENE earthquakes near Arroyo Municipio
Guayama Municipio, PR 7 km (5 mi) WNW earthquakes near Guayama Municipio
Patillas Municipio, PR 10 km (6 mi) ENE earthquakes near Patillas Municipio
Cayey Municipio, PR 18 km (11 mi) NNW earthquakes near Cayey Municipio
Maunabo Municipio, PR 19 km (12 mi) ENE earthquakes near Maunabo Municipio
Salinas Municipio, PR 20 km (13 mi) W earthquakes near Salinas Municipio

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

Aftershocks so far

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

  1. 2.8 3 km SSW of G. L. Garcia, Puerto Rico
  2. 2.6 2 km ESE of Potala Pastillo, Puerto Rico
  3. 3.5 6 km NW of Trujillo Alto, Puerto Rico
  4. 2.7 7 km SSE of Potala Pastillo, Puerto Rico
  5. 3.1 3 km ESE of Jauca, Puerto Rico
  6. 2.9 2 km ESE of Jauca, Puerto Rico
  7. 2.4 0 km N of Cidra, Puerto Rico
  8. 3.1 4 km SE of Jauca, Puerto Rico
  9. 2.7 0 km E of Luis Llorens Torres, Puerto Rico
  10. 2.9 2 km W of Potala Pastillo, Puerto Rico
  11. 2.7 2 km SSW of Jauca, Puerto Rico
  12. 3.0 3 km S of Palomas, 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.