QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Mona Passage

Yes. A magnitude 2.5 earthquake was recorded in Mona Passage, 20 km (12 mi) NW of Mayagüez, PR, at 8:56 pm AST on 31 December 2017 (00:56 UTC), 21 km deep.

20 km (12 mi) NW of Mayagüez, PR · 128 km (80 mi) W of San Juan, PR

· 21 km deep · released about 180 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Rincón Municipio 3 kmAguada Municipio 11 kmAñasco Municipio 16 kmMoca Municipio 22 kmAguadilla Municipio 22 kmHormigueros Municipio 27 kmSan Sebastián Municipio 32 kmIsabela Municipio 33 kmLas Marías Municipio 33 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 2.5 (md)
Depth
21 km below the surface
Felt
no reports yet
Nearest
Rincón Municipio, 3 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3237 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, people at rest would likely notice it out to about 8 km (5 mi) from the epicentre. 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: Rincón 3 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 180 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 86,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 61,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.4× the energy of this one
  4. This earthquake M 2.5 about 180 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 in our catalogue was M 4.3 on 2017-10-14 — about 480 times the energy of this one.

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 18.3251, -67.2765. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Rincón Municipio, PR 3 km (2 mi) ENE earthquakes near Rincón Municipio
Aguada Municipio, PR 11 km (7 mi) ENE earthquakes near Aguada Municipio
Añasco Municipio, PR 16 km (10 mi) ESE earthquakes near Añasco Municipio
Moca Municipio, PR 22 km (13 mi) ENE earthquakes near Moca Municipio
Aguadilla Municipio, PR 22 km (14 mi) NE earthquakes near Aguadilla Municipio
Hormigueros Municipio, PR 27 km (17 mi) SE earthquakes near Hormigueros Municipio

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

Aftershocks so far

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

  1. 3.0 13 km NE of Isabela, Puerto Rico
  2. 2.8 13 km N of Isabela, Puerto Rico
  3. 2.1 1 km W of Sabana Grande, Puerto Rico
  4. 2.4 8 km W of Mayagüez, Puerto Rico
  5. 2.7 24 km WNW of Rincón, Puerto Rico
  6. 3.0 16 km W of Rincón, Puerto Rico
  7. 1.9 2 km ESE of La Playa, Puerto Rico
  8. 2.2 26 km W of Pole Ojea, Puerto Rico
  9. 2.1 5 km W of Boquerón, Puerto Rico
  10. 2.2 6 km WSW of Puerto Real, Puerto Rico
  11. 2.9 17 km NNW of Rincón, Puerto Rico
  12. 2.1 2 km SW of La Parguera, Puerto Rico
  13. 2.8 Mona Passage
  14. 3.3 42 km NW of San Antonio, Puerto Rico
  15. 1.9 1 km SSE of La Playa, 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.