QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

56 km WNW of Rincón, Puerto Rico

Yes. A magnitude 3.0 earthquake was recorded 56 km WNW of Rincón, Puerto Rico, at 3:53 pm AST on 4 August 2018 (19:53 UTC), 90 km deep.

· 90 km deep · released about 890 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Mayagüez Municipio 43 kmRincón Municipio 56 kmAguada Municipio 62 kmAguadilla Municipio 66 kmAñasco Municipio 70 kmMoca Municipio 73 kmHormigueros Municipio 78 kmIsabela Municipio 80 kmCabo Rojo Municipio 80 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 3.0 (md)
Depth
90 km below the surface
Felt
no reports yet
Nearest
Mayagüez Municipio, 43 km SSW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2948 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 it was probably too small to be felt, even directly above it. 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 890 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.0 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 380,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 17,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 12,000× the energy of this one
  4. This earthquake M 3.0 about 890 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 4.4 on 2017-10-01 — about 130 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 6.4 32 km NW of Aguadilla, Puerto Rico · 44 km ENE of this epicentre
  2. 6.3 58 km E of Punta Cana, Dominican Republic · 11 km WNW 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 18.4576, -67.7680. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Mayagüez Municipio, PR 43 km (27 mi) SSW earthquakes near Mayagüez Municipio
Rincón Municipio, PR 56 km (35 mi) ESE earthquakes near Rincón Municipio
Aguada Municipio, PR 62 km (39 mi) E earthquakes near Aguada Municipio
Aguadilla Municipio, PR 66 km (41 mi) E earthquakes near Aguadilla Municipio
Añasco Municipio, PR 70 km (43 mi) ESE earthquakes near Añasco Municipio
Moca Municipio, PR 73 km (45 mi) E earthquakes near Moca Municipio

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

Aftershocks so far

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

  1. 2.7 51 km ENE of Punta Cana, Dominican Republic
  2. 2.9 23 km SW of Stella, Puerto Rico
  3. 2.1 35 km WNW of Rincón, Puerto Rico
  4. 2.5 23 km WNW of Rincón, Puerto Rico
  5. 2.3 53 km WSW of Stella, Puerto Rico
  6. 2.6 8 km W of Rincón, Puerto Rico
  7. 2.3 42 km WSW of Stella, Puerto Rico
  8. 2.7 36 km WSW of Stella, Puerto Rico
  9. 3.0 53 km ENE of Punta Cana, Dominican Republic
  10. 2.8 72 km WSW of Stella, Puerto Rico
  11. 2.5 50 km NW of San Antonio, Puerto Rico
  12. 2.0 10 km WNW of Rincón, Puerto Rico
  13. 3.2 56 km SE of Punta Cana, Dominican Republic
  14. 2.6 21 km W of Rincón, Puerto Rico
  15. 2.9 63 km W of Rincón, 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.