QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near Arroyo, PR

No earthquake was likely felt in Arroyo in the 24 hours to 12:10 pm AST (16:10 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 2.5 earthquake was recorded 23 km (14 mi) south-southeast of Arroyo, PR, at 10:46 am AST on 30 August 2017 (14:46 UTC), 3.0 km deep.

USGS: 23 km SSE of Arroyo, Puerto Rico

71 km (44 mi) S of San Juan, PR · 52 km (32 mi) S of Caguas, PR

10:46 am AST, Aug 30, 2017 · · 3.0 km deep · released about 190 lb of TNT

Every earthquake near Arroyo Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Arroyo Municipio 23 kmPatillas Municipio 26 kmMaunabo Municipio 28 kmGuayama Municipio 28 kmYabucoa Municipio 35 kmSalinas Municipio 37 kmCayey Municipio 41 kmSan Lorenzo Municipio 42 kmHumacao Municipio 46 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
10:46 am AST on 30 August 2017 ()
Where
23 km (14 mi) south-southeast of Arroyo, PR · earthquakes near Arroyo
Magnitude
M 2.5 (md)
Depth
3.0 km below the surface
Felt
no reports yet
Nearest
Arroyo Municipio, 23 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3270 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 22 km (14 mi) from the epicentre. In Arroyo, 23 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.

Earthquakes near other towns within 30 km: Lamboglia, Palmas, Buena Vista, Patillas, Corazón, Palo Seco.

How big was it?

This earthquake released about 190 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 80,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 57,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.1× the energy of this one
  4. This earthquake M 2.5 about 190 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 1,300 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 17.7681, -65.9880. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Arroyo Municipio, PR 23 km (15 mi) NNW earthquakes near Arroyo Municipio
Patillas Municipio, PR 26 km (16 mi) N earthquakes near Patillas Municipio
Maunabo Municipio, PR 28 km (17 mi) NNE earthquakes near Maunabo Municipio
Guayama Municipio, PR 28 km (17 mi) NW earthquakes near Guayama Municipio
Yabucoa Municipio, PR 35 km (22 mi) NNE earthquakes near Yabucoa Municipio
Salinas Municipio, PR 37 km (23 mi) NW earthquakes near Salinas 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. 2.3 2 km ESE of Humacao, Puerto Rico
  2. 2.0 9 km SSW of Central Aguirre, Puerto Rico
  3. 2.2 9 km SSE of Jobos, Puerto Rico
  4. 2.4 14 km SSE of Central Aguirre, Puerto Rico
  5. 2.7 1 km NE of Jauca, Puerto Rico
  6. 2.7 1 km S of G. L. Garcia, Puerto Rico
  7. 2.7 10 km S of Jobos, Puerto Rico
  8. 1.5 3 km SSW of Arroyo, Puerto Rico
  9. 2.4 5 km N of Yaurel, Puerto Rico
  10. 3.0 4 km SE of G. L. Garcia, Puerto Rico
  11. 1.5 10 km S of Jobos, Puerto Rico
  12. 3.1 4 km SSE of Palo Seco, Puerto Rico
  13. 2.8 18 km SSE of Arroyo, Puerto Rico
  14. 1.6 20 km S of Arroyo, Puerto Rico
  15. 3.1 12 km SE of Punta Santiago, 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.