QuakeIndex

Earthquake · reviewed by a seismologist

M 3.3md

Earthquake near Trujillo Alto, PR

No earthquake was likely felt in Trujillo Alto in the 24 hours to 9:35 am AST (13:35 UTC). The last one was M 4.1, 83 km (52 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 Trujillo Alto

This page: a magnitude 3.3 earthquake was recorded 3 km (2 mi) southeast of Trujillo Alto, PR, at 3:53 pm AST on 15 December 2022 (19:53 UTC), 113 km deep. 1 person has reported feeling it to USGS.

USGS: 3 km SE of Trujillo Alto, Puerto Rico

11 km (7 mi) SE of San Juan, PR · 9 km (5 mi) S of Carolina, PR

3:53 pm AST, Dec 15, 2022 · · 113 km deep · released about 1.1 tons of TNT

10 km30 km60 km120 km N Trujillo Alto Municipio 2 kmGurabo Municipio 7 kmCarolina Municipio 7 kmCanóvanas Municipio 10 kmLoíza Municipio 13 kmSan Juan Municipio 13 kmGuaynabo Municipio 14 kmJuncos Municipio 15 kmCaguas Municipio 15 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
3:53 pm AST on 15 December 2022 ()
Where
3 km (2 mi) southeast of Trujillo Alto, PR · earthquakes near Trujillo Alto
Magnitude
M 3.3 (md)
Depth
113 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Trujillo Alto Municipio, 2 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1362 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 Trujillo Alto, 3 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: Carolina, Celada, Gurabo, Campo Rico, Santa Barbara, Canovanas.

How big was it?

This earthquake released about 1.1 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.3 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 150,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 6,700× the energy of this one
  3. Magna, Utah 2020 M 5.7 4,700× the energy of this one
  4. This earthquake M 3.3 about 1.1 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 2.4× 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 110 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.1 3 km W of Aguas Buenas, Puerto Rico · 18 km WSW of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 42 km WNW 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 18.3343, -65.9845. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Trujillo Alto Municipio, PR 2 km (1 mi) W earthquakes near Trujillo Alto Municipio
Gurabo Municipio, PR 7 km (4 mi) S earthquakes near Gurabo Municipio
Carolina Municipio, PR 7 km (4 mi) NNE earthquakes near Carolina Municipio
Canóvanas Municipio, PR 10 km (6 mi) E earthquakes near Canóvanas Municipio
Loíza Municipio, PR 13 km (8 mi) NNE earthquakes near Loíza Municipio
San Juan Municipio, PR 13 km (8 mi) NW earthquakes near San Juan Municipio

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

Aftershocks so far

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

  1. 3.4 3 km NNE of Benitez, Puerto Rico
  2. 2.8 0 km SSW of San Juan, Puerto Rico
  3. 2.5 0 km N of Vázquez, Puerto Rico
  4. 2.9 2 km NNW of Punta Santiago, Puerto Rico
  5. 2.1 6 km NE of Orocovis, Puerto Rico
  6. 2.3 10 km S of Emajagua, Puerto Rico
  7. 2.7 2 km WNW of Campo Rico, Puerto Rico
  8. 3.0 3 km WSW of La Plena, Puerto Rico
  9. 2.6 6 km SSW of Lamboglia, Puerto Rico
  10. 2.8 Puerto Rico region
  11. 2.2 Puerto Rico region
  12. 3.1 Puerto Rico region
  13. 2.8 1 km W of San Isidro, Puerto Rico
  14. 2.0 1 km SSW of Vázquez, Puerto Rico
  15. 3.2 3 km NNW of San Juan, 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.