QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Maricao, PR

No earthquake was likely felt in Maricao in the 24 hours to 1:58 am AST (05:58 UTC). The last one was M 3.0, 33 km (20 mi) SSE, at 3:45 am AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Maricao

This page: a magnitude 1.8 earthquake was recorded 2 km (1 mi) north-northeast of Maricao, PR, at 7:39 pm AST on 15 December 2018 (23:39 UTC), 4.0 km deep.

USGS: 2 km NNE of Maricao, Puerto Rico

99 km (61 mi) WSW of San Juan, PR · 18 km (11 mi) E of Mayagüez, PR

7:39 pm AST, Dec 15, 2018 · · 4.0 km deep · released about 17 lb of TNT

Every earthquake near Maricao Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Las Marías Municipio 3 kmMaricao Municipio 5 kmSan Germán Municipio 12 kmSabana Grande Municipio 13 kmLares Municipio 14 kmSan Sebastián Municipio 15 kmHormigueros Municipio 17 kmYauco Municipio 18 kmAñasco Municipio 19 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
7:39 pm AST on 15 December 2018 ()
Where
2 km (1 mi) north-northeast of Maricao, PR · earthquakes near Maricao
Magnitude
M 1.8 (md)
Depth
4.0 km below the surface
Felt
no reports yet
Nearest
Las Marías Municipio, 3 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2888 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 13 km (8 mi) from the epicentre. In Maricao, 2 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: Sabana Grande, Juncal, Lares, San Germán, San Sebastián, Sabana Eneas.

How big was it?

This earthquake released about 17 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 5.8 900,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 640,000× the energy of this one
  3. Around the size people start to feel M 3.0 57× the energy of this one
  4. This earthquake M 1.8 about 17 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 5 earthquakes of M5 or more within 50 km:

  1. 6.3 6 km WNW of Aguadilla, Puerto Rico · 37 km NW of this epicentre
  2. 6.1 15 km WNW of San Antonio, Puerto Rico · 48 km NW of this epicentre
  3. 5.8 4 km E of Moca, Puerto Rico · 24 km NNW of this epicentre
  4. 5.2 19 km SW of Stella, Puerto Rico · 42 km W of this epicentre
  5. 5.1 21 km SW of Stella, Puerto Rico · 42 km W 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 18.1996, -66.9748. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Las Marías Municipio, PR 3 km (2 mi) N earthquakes near Las Marías Municipio
Maricao Municipio, PR 5 km (3 mi) SE earthquakes near Maricao Municipio
San Germán Municipio, PR 12 km (8 mi) SSW earthquakes near San Germán Municipio
Sabana Grande Municipio, PR 13 km (8 mi) SSE earthquakes near Sabana Grande Municipio
Lares Municipio, PR 14 km (9 mi) NE earthquakes near Lares Municipio
San Sebastián Municipio, PR 15 km (9 mi) N earthquakes near San Sebastián Municipio

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

Aftershocks so far

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

  1. 1.8 2 km WSW of Tallaboa, Puerto Rico
  2. 2.1 9 km S of Tallaboa, Puerto Rico
  3. 1.9 8 km S of Tallaboa, Puerto Rico
  4. 2.0 10 km SSE of Tallaboa, Puerto Rico
  5. 1.9 2 km WSW of Tallaboa, Puerto Rico
  6. 1.8 2 km SW of Tallaboa, Puerto Rico
  7. 2.0 9 km S of Tallaboa, Puerto Rico
  8. 2.0 8 km S of Tallaboa, Puerto Rico
  9. 2.0 Puerto Rico region
  10. 2.4 5 km SE of Indios, Puerto Rico
  11. 2.2 9 km S of Tallaboa, Puerto Rico
  12. 1.8 9 km S of Tallaboa, Puerto Rico
  13. 2.2 Puerto Rico region
  14. 1.6 8 km SSW of Tallaboa, Puerto Rico
  15. 2.6 8 km S of Tallaboa, 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.