QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

Earthquake near Punta Santiago, PR

No earthquake was likely felt in Punta Santiago in the 24 hours to 1:38 pm AST (17:38 UTC). The last one was M 4.1, 49 km (31 mi) ESE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near Punta Santiago

This page: a magnitude 3.1 earthquake was recorded 13 km (8 mi) southeast of Punta Santiago, PR, at 10:45 am AST on 11 January 2018 (14:45 UTC), 62 km deep.

USGS: 12 km SE of Punta Santiago, Puerto Rico

55 km (34 mi) SE of San Juan, PR · 42 km (26 mi) ESE of Caguas, PR

10:45 am AST, Jan 11, 2018 · · 62 km deep · released about 1,300 lb of TNT

Every earthquake near Punta Santiago Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Humacao Municipio 14 kmNaguabo Municipio 16 kmYabucoa Municipio 20 kmCeiba Municipio 20 kmLas Piedras Municipio 24 kmMaunabo Municipio 25 kmVieques Municipio 26 kmJuncos Municipio 30 kmLuquillo Municipio 32 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
10:45 am AST on 11 January 2018 ()
Where
13 km (8 mi) southeast of Punta Santiago, PR · earthquakes near Punta Santiago
Magnitude
M 3.1 (md)
Depth
62 km below the surface
Felt
no reports yet
Nearest
Humacao Municipio, 14 km WNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3145 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 it was probably too small to be felt, even directly above it. In Punta Santiago, 13 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: Bajandas, Naguabo, Daguao, Candelero Arriba, Comunas, Humacao.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 260,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 12,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 8,200× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× more

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 4.6 on 2016-12-05 — about 180 times the energy of this one.

Before 2016, the USGS record since 1900 lists no earthquake of M5 or more within 50 km.

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 18.0781, -65.6718. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Humacao Municipio, PR 14 km (8 mi) WNW earthquakes near Humacao Municipio
Naguabo Municipio, PR 16 km (10 mi) NNW earthquakes near Naguabo Municipio
Yabucoa Municipio, PR 20 km (12 mi) W earthquakes near Yabucoa Municipio
Ceiba Municipio, PR 20 km (13 mi) NNE earthquakes near Ceiba Municipio
Las Piedras Municipio, PR 24 km (15 mi) WNW earthquakes near Las Piedras Municipio
Maunabo Municipio, PR 25 km (16 mi) WSW earthquakes near Maunabo Municipio

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

Aftershocks so far

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

  1. 2.4 5 km SE of Arroyo, Puerto Rico
  2. 1.7 5 km SSW of Lamboglia, Puerto Rico
  3. 2.2 2 km E of Arroyo, Puerto Rico
  4. 2.2 5 km SSW of Lamboglia, Puerto Rico
  5. 2.1 4 km ESE of Arroyo, Puerto Rico
  6. 1.8 2 km S of Palmas, Puerto Rico
  7. 1.6 4 km SSE of Palmas, Puerto Rico
  8. 2.0 4 km S of Palmas, Puerto Rico
  9. 1.5 5 km SSW of Lamboglia, Puerto Rico
  10. 1.9 1 km NNE of Buena Vista, Puerto Rico
  11. 2.0 0 km S of Palmas, Puerto Rico
  12. 1.7 5 km SSW of Lamboglia, Puerto Rico
  13. 2.3 5 km SSW of Lamboglia, Puerto Rico
  14. 2.0 1 km NNE of Buena Vista, Puerto Rico
  15. 2.3 5 km SSW of Lamboglia, 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.