QuakeIndex

Earthquake · reviewed by a seismologist

M 3.5Md

59 km NW of Rincón, Puerto Rico

Yes. A magnitude 3.5 earthquake was recorded 59 km NW of Rincón, Puerto Rico, at 4:13 am AST on 26 August 2016 (08:13 UTC), 30 km deep.

· 30 km deep · released about 2.7 tons of TNT

10 km30 km60 km120 km N Rincón Municipio 59 kmAguadilla Municipio 60 kmAguada Municipio 62 kmMoca Municipio 71 kmMayagüez Municipio 72 kmAñasco Municipio 73 kmIsabela Municipio 73 kmQuebradillas Municipio 82 kmSan Sebastián Municipio 84 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
Magnitude
M 3.5 (Md)
Depth
30 km below the surface
Felt
no reports yet
Nearest
Rincón Municipio, 59 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3635 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 56 km (35 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.

How big was it?

This earthquake released about 2.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 63,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 2,800× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,000× the energy of this one
  4. This earthquake M 3.5 about 2.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 5.6× 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

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

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

  1. 6.8 94 km NE of Punta Cana, Dominican Republic · 48 km N of this epicentre
  2. 6.4 32 km NW of Aguadilla, Puerto Rico · 31 km ESE of this epicentre
  3. 6.3 58 km E of Punta Cana, Dominican Republic · 30 km SW of this epicentre
  4. 6.1 15 km WNW of San Antonio, Puerto Rico · 49 km ESE of this epicentre
  5. 5.8 33 km NW of San Antonio, Puerto Rico · 37 km E 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 18.6970, -67.6666. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Rincón Municipio, PR 59 km (37 mi) SE earthquakes near Rincón Municipio
Aguadilla Municipio, PR 60 km (37 mi) ESE earthquakes near Aguadilla Municipio
Aguada Municipio, PR 62 km (39 mi) SE earthquakes near Aguada Municipio
Moca Municipio, PR 71 km (44 mi) ESE earthquakes near Moca Municipio
Mayagüez Municipio, PR 72 km (45 mi) SSW earthquakes near Mayagüez Municipio
Añasco Municipio, PR 73 km (45 mi) SE earthquakes near Añasco Municipio

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

Aftershocks so far

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

  1. 3.1 41 km NW of San Antonio, Puerto Rico
  2. 2.8 47 km NW of Rincón, Puerto Rico
  3. 2.7 58 km NW of Aguadilla, Puerto Rico
  4. 2.9 80 km NE of Punta Cana, Dominican Republic
  5. 3.1 56 km ENE of Punta Cana, Dominican Republic
  6. 2.1 22 km NW of Rincón, Puerto Rico
  7. 2.4 24 km NW of Rincón, Puerto Rico
  8. 3.4 69 km NE of Punta Cana, Dominican Republic
  9. 3.2 63 km NW of San Antonio, Puerto Rico
  10. 3.4 52 km ESE of Punta Cana, Dominican Republic
  11. 3.0 Mona Passage
  12. 3.0 70 km NE of Punta Cana, Dominican Republic
  13. 3.0 89 km NW of San Antonio, Puerto Rico
  14. 2.7 59 km NE of Punta Cana, Dominican Republic
  15. 2.0 48 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.