QuakeIndex

Earthquake · reviewed by a seismologist

M 3.0md

Earthquake near Isabela, PR

No earthquake was likely felt in Isabela in the 24 hours to 4:07 pm AST (20:07 UTC). The last one was M 3.4, 31 km (19 mi) N, at 9:00 pm AST on 27 October 2026, estimated intensity II (weak) in town. Every earthquake near Isabela

This page: a magnitude 3.0 earthquake was recorded 31 km (19 mi) north-northwest of Isabela, PR, at 11:37 pm AST on 15 August 2019 (03:37 UTC), 58 km deep. 2 people have reported feeling it to USGS.

USGS: 30 km N of San Antonio, Puerto Rico

53 km (33 mi) NW of Arecibo, PR · 118 km (73 mi) WNW of San Juan, PR

11:37 pm AST, Aug 15, 2019 · · 58 km deep · released about 860 lb of TNT

Every earthquake near Isabela Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aguadilla Municipio 32 kmIsabela Municipio 33 kmQuebradillas Municipio 39 kmMoca Municipio 43 kmAguada Municipio 44 kmCamuy Municipio 44 kmHatillo Municipio 49 kmRincón Municipio 50 kmSan Sebastián Municipio 51 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
11:37 pm AST on 15 August 2019 ()
Where
31 km (19 mi) north-northwest of Isabela, PR · earthquakes near Isabela
Magnitude
M 3.0 (md)
Depth
58 km below the surface
Felt
2 reports · strongest reported intensity II
Nearest
Aguadilla Municipio, 32 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2566 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. In Isabela, 31 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.

How big was it?

This earthquake released about 860 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 6.7 390,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 18,000× 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 860 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 4.3 on 2017-10-14 — about 99 times the energy of this one.

Before 2016, the USGS record lists 18 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.7 45 km N of San Antonio, Puerto Rico · 16 km N of this epicentre
  2. 7.1 24 km NNW of San Antonio, Puerto Rico · 11 km SW of this epicentre
  3. 6.4 32 km NW of Aguadilla, Puerto Rico · 33 km WSW of this epicentre
  4. 6.4 61 km N of Hatillo, Puerto Rico · 44 km NE of this epicentre
  5. 6.3 6 km WNW of Aguadilla, Puerto Rico · 38 km SSW 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 18.7655, -67.1123. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aguadilla Municipio, PR 32 km (20 mi) S earthquakes near Aguadilla Municipio
Isabela Municipio, PR 33 km (20 mi) SSE earthquakes near Isabela Municipio
Quebradillas Municipio, PR 39 km (24 mi) SSE earthquakes near Quebradillas Municipio
Moca Municipio, PR 43 km (27 mi) S earthquakes near Moca Municipio
Aguada Municipio, PR 44 km (27 mi) S earthquakes near Aguada Municipio
Camuy Municipio, PR 44 km (27 mi) SE earthquakes near Camuy Municipio

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

Aftershocks so far

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

  1. 3.8 46 km N of San Antonio, Puerto Rico
  2. 2.2 66 km N of San Antonio, Puerto Rico
  3. 6.0 67 km NNW of San Antonio, Puerto Rico
  4. 2.2 18 km N of Hatillo, Puerto Rico
  5. 2.9 68 km N of Isabela, Puerto Rico
  6. 2.4 8 km NNE of Carrizales, Puerto Rico
  7. 2.6 17 km N of Hatillo, Puerto Rico
  8. 2.6 39 km NW of San Antonio, Puerto Rico
  9. 2.3 10 km WNW of San Antonio, Puerto Rico
  10. 1.9 57 km N of Isabela, Puerto Rico
  11. 2.6 1 km NNW of Moca, Puerto Rico
  12. 2.4 37 km NNW of San Antonio, Puerto Rico
  13. 2.7 45 km NNW of San Antonio, Puerto Rico
  14. 2.1 45 km N of Hatillo, Puerto Rico
  15. 2.5 45 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.