Earthquake near San Juan, PR

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 San Juan, 10 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: Levittown, Cataño, Sabana Seca, Ingenio, Candelaria Arenas, Dorado.

How big was it?

This earthquake released about 2.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 61,000× the energy of this one
2. Mineral, Virginia 2011 M 5.8 2,700× the energy of this one
3. Magna, Utah 2020 M 5.7 1,900× the energy of this one
4. This earthquake M 3.5 about 2.8 tons of TNT
5. Around the size people start to feel M 3.0 this one released 5.8× 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 4.8 on 2017-08-18 — about 86 times the energy of this one.

Before 2016, the USGS record lists 3 earthquakes of M5 or more within 50 km:

1. 5.8 12 km N of Garrochales, Puerto Rico · 45 km W of this epicentre Oct 12, 1918
2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 32 km S of this epicentre Dec 24, 2010
3. 5.0 3 km N of Brenas, Puerto Rico · 21 km WSW of this epicentre Jun 17, 1975

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 18.5443, -66.1428. Map © OpenStreetMap contributors.

Nearby places

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. 2.9 6 km NNW of Loíza, Puerto Rico 20:06 UTC
2. 3.1 47 km N of Brenas, Puerto Rico 13:25 UTC
3. 3.5 22 km N of Brenas, Puerto Rico 19:56 UTC
4. 2.3 6 km ENE of Naranjito, Puerto Rico 16:34 UTC
5. 3.0 38 km NNW of Brenas, Puerto Rico 11:37 UTC
6. 1.8 1 km WSW of G. L. Garcia, Puerto Rico 23:47 UTC
7. 3.2 2 km SW of G. L. Garcia, Puerto Rico 04:14 UTC
8. 3.0 34 km NNE of Suárez, Puerto Rico 08:57 UTC
9. 3.0 9 km NNW of Sabana, Puerto Rico 07:56 UTC
10. 3.0 46 km N of San Juan, Puerto Rico 16:20 UTC
11. 3.3 4 km WNW of Trujillo Alto, Puerto Rico 07:00 UTC
12. 3.3 3 km SE of Naranjito, Puerto Rico 09:07 UTC
13. 2.5 11 km NNE of Tierras Nuevas Poniente, Puerto Rico 12:25 UTC
14. 2.9 7 km NNW of Tierras Nuevas Poniente, Puerto Rico 22:48 UTC
15. 3.2 23 km NNW of Brenas, Puerto Rico 14:39 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 13:35 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.