QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Loíza, PR

No earthquake was likely felt in Loíza in the 24 hours to 4:29 pm AST (20:29 UTC). The last one was M 4.1, 78 km (48 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Loíza

This page: a magnitude 1.8 earthquake was recorded 20 km (12 mi) north-northwest of Loíza, PR, at 2:34 pm AST on 8 April 2019 (18:34 UTC), 67 km deep.

USGS: 19 km NNW of Loíza, Puerto Rico

25 km (16 mi) NNE of San Juan, PR · 21 km (13 mi) N of Carolina, PR

2:34 pm AST, Apr 8, 2019 · · 67 km deep · released about 13 lb of TNT

Every earthquake near Loíza Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Loíza Municipio 17 kmCarolina Municipio 23 kmSan Juan Municipio 24 kmCataño Municipio 28 kmRío Grande Municipio 29 kmTrujillo Alto Municipio 30 kmCanóvanas Municipio 31 kmToa Baja Municipio 31 kmGuaynabo Municipio 34 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
2:34 pm AST on 8 April 2019 ()
Where
20 km (12 mi) north-northwest of Loíza, PR · earthquakes near Loíza
Magnitude
M 1.8 (md)
Depth
67 km below the surface
Felt
no reports yet
Nearest
Loíza Municipio, 17 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2774 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Loíza, 20 km away, the estimate is intensity I (not felt). 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: Suárez, San Juan, Vieques, Santa Barbara, San Isidro, Eleanor Roosevelt.

How big was it?

This earthquake released about 13 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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

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

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

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 43 km SSW of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 43 km WSW 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 18.6000, -65.9440. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Loíza Municipio, PR 17 km (11 mi) S earthquakes near Loíza Municipio
Carolina Municipio, PR 23 km (14 mi) S earthquakes near Carolina Municipio
San Juan Municipio, PR 24 km (15 mi) SSW earthquakes near San Juan Municipio
Cataño Municipio, PR 28 km (17 mi) SW earthquakes near Cataño Municipio
Río Grande Municipio, PR 29 km (18 mi) SSE earthquakes near Río Grande Municipio
Trujillo Alto Municipio, PR 30 km (19 mi) SSW earthquakes near Trujillo Alto 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. 1.9 20 km NNE of Luquillo, Puerto Rico
  2. 2.1 19 km N of Brenas, Puerto Rico
  3. 2.7 64 km N of San Juan, Puerto Rico
  4. 2.1 2 km ENE of Celada, Puerto Rico
  5. 1.8 11 km NNW of San Juan, Puerto Rico
  6. 2.3 25 km N of Brenas, Puerto Rico
  7. 1.7 5 km E of San Juan, Puerto Rico
  8. 2.3 6 km NW of Trujillo Alto, Puerto Rico
  9. 1.7 5 km NNW of Brenas, Puerto Rico
  10. 2.4 0 km E of Río Lajas, Puerto Rico
  11. 2.1 39 km N of Dorado, Puerto Rico
  12. 2.7 44 km N of San Juan, Puerto Rico
  13. 2.3 27 km N of Brenas, Puerto Rico
  14. 1.8 12 km N of San Juan, Puerto Rico
  15. 2.7 2 km NNE of Levittown, 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.