QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Puerto Real, PR

No earthquake was likely felt in Puerto Real in the 24 hours to 7:24 pm AST (23:24 UTC). The last one was M 2.1, 10 km (6 mi) SE, at 11:57 pm AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Puerto Real

This page: a magnitude 2.1 earthquake was recorded 16 km (10 mi) west-northwest of Puerto Real, PR, at 3:03 am AST on 16 March 2018 (07:03 UTC), 32 km deep.

USGS: 16 km WNW of Puerto Real, Puerto Rico

22 km (13 mi) WSW of Mayagüez, PR · 137 km (85 mi) WSW of San Juan, PR

3:03 am AST, Mar 16, 2018 · · 32 km deep · released about 46 lb of TNT

Every earthquake near Puerto Real Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Cabo Rojo Municipio 21 kmHormigueros Municipio 23 kmRincón Municipio 25 kmAñasco Municipio 28 kmSan Germán Municipio 31 kmAguada Municipio 32 kmLajas Municipio 35 kmMoca Municipio 38 kmLas Marías Municipio 39 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
3:03 am AST on 16 March 2018 ()
Where
16 km (10 mi) west-northwest of Puerto Real, PR · earthquakes near Puerto Real
Magnitude
M 2.1 (md)
Depth
32 km below the surface
Felt
no reports yet
Nearest
Cabo Rojo Municipio, 21 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3163 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 Puerto Real, 16 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: Cabo Rojo, Boquerón, Hormigueros, Mayagüez, Pole Ojea, Stella.

How big was it?

This earthquake released about 46 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 330,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 230,000× the energy of this one
  3. Around the size people start to feel M 3.0 21× the energy of this one
  4. This earthquake M 2.1 about 46 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 1,900 times the energy of this one.

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 NNE of this epicentre
  2. 6.1 15 km WNW of San Antonio, Puerto Rico · 48 km NNE of this epicentre
  3. 5.8 4 km E of Moca, Puerto Rico · 41 km NE of this epicentre
  4. 5.2 19 km SW of Stella, Puerto Rico · 8 km NNW of this epicentre
  5. 5.1 21 km SW of Stella, Puerto Rico · 7 km NW 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 18.1271, -67.3308. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Cabo Rojo Municipio, PR 21 km (13 mi) SE earthquakes near Cabo Rojo Municipio
Hormigueros Municipio, PR 23 km (14 mi) E earthquakes near Hormigueros Municipio
Rincón Municipio, PR 25 km (16 mi) NNE earthquakes near Rincón Municipio
Añasco Municipio, PR 28 km (17 mi) NE earthquakes near Añasco Municipio
San Germán Municipio, PR 31 km (19 mi) E earthquakes near San Germán Municipio
Aguada Municipio, PR 32 km (20 mi) NNE earthquakes near Aguada Municipio

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

Aftershocks so far

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

  1. 2.1 3 km E of Las Marías, Puerto Rico
  2. 1.8 6 km ESE of Las Marías, Puerto Rico
  3. 2.1 3 km ENE of Las Marías, Puerto Rico
  4. 1.9 1 km SSE of Las Marías, Puerto Rico
  5. 2.8 2 km ESE of Las Marías, Puerto Rico
  6. 2.3 3 km ESE of Las Marías, Puerto Rico
  7. 2.4 3 km ESE of Las Marías, Puerto Rico
  8. 1.9 5 km ESE of Las Marías, Puerto Rico
  9. 2.4 3 km ESE of Las Marías, Puerto Rico
  10. 2.4 1 km NNW of La Playa, Puerto Rico
  11. 2.2 29 km SW of Stella, Puerto Rico
  12. 2.4 2 km SSW of Sabana Grande, Puerto Rico
  13. 2.5 22 km WNW of Rincón, Puerto Rico
  14. 1.5 17 km WNW of Puerto Real, Puerto Rico
  15. 1.8 2 km NE of Boquerón, 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.