QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near Moca, PR

No earthquake was likely felt in Moca in the 24 hours to 5:35 pm AST (21:35 UTC). The last one was M 3.5, in Moca, at 12:03 am AST on 6 November 2026, estimated intensity II (weak) in town. Every earthquake near Moca

This page: a magnitude 2.5 earthquake was recorded 4 km (2 mi) east of Moca, PR, at 8:14 pm AST on 16 October 2018 (00:14 UTC), 18 km deep.

USGS: 3 km E of Moca, Puerto Rico

23 km (14 mi) NNE of Mayagüez, PR · 107 km (66 mi) W of San Juan, PR

8:14 pm AST, Oct 16, 2018 · · 18 km deep · released about 160 lb of TNT

Every earthquake near Moca Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Moca Municipio 2 kmAguadilla Municipio 12 kmIsabela Municipio 12 kmAguada Municipio 12 kmSan Sebastián Municipio 14 kmAñasco Municipio 14 kmQuebradillas Municipio 17 kmRincón Municipio 20 kmLas Marías Municipio 22 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
8:14 pm AST on 16 October 2018 ()
Where
4 km (2 mi) east of Moca, PR · earthquakes near Moca
Magnitude
M 2.5 (md)
Depth
18 km below the surface
Felt
no reports yet
Nearest
Moca Municipio, 2 km S
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2948 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 Moca, 4 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.

Likely felt in: Rafael Hernandez 8 km, intensity II · Aguadilla 9 km, intensity II · San Sebastián 11 km, intensity II · Aguada 12 km, intensity II · Isabela 13 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 160 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 92,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 65,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.8× the energy of this one
  4. This earthquake M 2.5 about 160 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 520 times the energy of this one.

Before 2016, the USGS record lists 10 earthquakes of M5 or more within 50 km; the five largest:

  1. 7.1 24 km NNW of San Antonio, Puerto Rico · 36 km NNW of this epicentre
  2. 6.4 32 km NW of Aguadilla, Puerto Rico · 40 km NW of this epicentre
  3. 6.3 6 km WNW of Aguadilla, Puerto Rico · 15 km WNW of this epicentre
  4. 6.1 15 km WNW of San Antonio, Puerto Rico · 24 km NW of this epicentre
  5. 6.1 18 km NNW of San Antonio, Puerto Rico · 29 km NNW 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 18.3985, -67.0763. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Moca Municipio, PR 2 km (1 mi) S earthquakes near Moca Municipio
Aguadilla Municipio, PR 12 km (7 mi) NW earthquakes near Aguadilla Municipio
Isabela Municipio, PR 12 km (7 mi) NE earthquakes near Isabela Municipio
Aguada Municipio, PR 12 km (7 mi) WSW earthquakes near Aguada Municipio
San Sebastián Municipio, PR 14 km (8 mi) ESE earthquakes near San Sebastián Municipio
Añasco Municipio, PR 14 km (9 mi) SSW earthquakes near Añasco Municipio

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

Aftershocks so far

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

  1. 1.6 10 km NW of Puerto Real, Puerto Rico
  2. 2.0 5 km NNW of Puerto Real, Puerto Rico
  3. 2.3 8 km NW of Puerto Real, Puerto Rico
  4. 1.7 7 km NW of Puerto Real, Puerto Rico
  5. 1.7 5 km NNW of Puerto Real, Puerto Rico
  6. 2.0 10 km NW of Puerto Real, Puerto Rico
  7. 1.7 Mona Passage
  8. 2.6 10 km NW of Puerto Real, Puerto Rico
  9. 2.9 9 km NW of Puerto Real, Puerto Rico
  10. 2.1 7 km NW of Puerto Real, Puerto Rico
  11. 2.1 8 km NW of Puerto Real, Puerto Rico
  12. 2.2 9 km NW of Puerto Real, Puerto Rico
  13. 1.9 6 km WNW of Puerto Real, Puerto Rico
  14. 2.1 2 km SSW of Mayagüez, Puerto Rico
  15. 1.9 5 km WNW of Puerto Real, 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.