QuakeIndex

Earthquake · reviewed by a seismologist

M 2.5md

Earthquake near San Antonio, PR

No earthquake was likely felt in San Antonio in the 24 hours to 10:19 am AST (14:19 UTC). The last one was M 4.8, 88 km (55 mi) SW, at 9:19 am AST on 18 September 2026, estimated intensity III (weak) in town; 86 felt reports to USGS. Every earthquake near San Antonio

This page: a magnitude 2.5 earthquake was recorded 2 km (1 mi) southwest of San Antonio, PR, at 12:43 am AST on 20 July 2022 (04:43 UTC), 48 km deep. 1 person has reported feeling it to USGS.

USGS: 2 km SW of San Antonio, Puerto Rico

27 km (17 mi) W of San Juan, PR · 18 km (11 mi) WNW of Bayamón, PR

12:43 am AST, Jul 20, 2022 · · 48 km deep · released about 170 lb of TNT

Every earthquake near San Antonio Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Vega Alta Municipio 2 kmDorado Municipio 7 kmVega Baja Municipio 9 kmToa Alta Municipio 11 kmToa Baja Municipio 14 kmCorozal Municipio 15 kmMorovis Municipio 17 kmNaranjito Municipio 18 kmCataño Municipio 18 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
12:43 am AST on 20 July 2022 ()
Where
2 km (1 mi) southwest of San Antonio, PR · earthquakes near San Antonio
Magnitude
M 2.5 (md)
Depth
48 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Vega Alta Municipio, 2 km W
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1575 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 San Antonio, 2 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: Vega Alta, Ceiba, Brenas, Monserrate, Sabana, Dorado.

How big was it?

This earthquake released about 170 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 89,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 63,000× the energy of this one
  3. Around the size people start to feel M 3.0 5.6× the energy of this one
  4. This earthquake M 2.5 about 170 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 4.4 on 2018-12-09 — about 710 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 · 30 km WNW of this epicentre
  2. 5.1 3 km W of Aguas Buenas, Puerto Rico · 28 km SE of this epicentre
  3. 5.0 3 km N of Brenas, Puerto Rico · 8 km NNW 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 18.4357, -66.3195. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Vega Alta Municipio, PR 2 km (1 mi) W earthquakes near Vega Alta Municipio
Dorado Municipio, PR 7 km (5 mi) NE earthquakes near Dorado Municipio
Vega Baja Municipio, PR 9 km (5 mi) WNW earthquakes near Vega Baja Municipio
Toa Alta Municipio, PR 11 km (7 mi) SE earthquakes near Toa Alta Municipio
Toa Baja Municipio, PR 14 km (8 mi) E earthquakes near Toa Baja Municipio
Corozal Municipio, PR 15 km (9 mi) S earthquakes near Corozal Municipio

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

Aftershocks so far

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

  1. 3.5 1 km NNW of Trujillo Alto, Puerto Rico
  2. 2.6 5 km WNW of Jagual, Puerto Rico
  3. 2.4 6 km ESE of Villalba, Puerto Rico
  4. 3.7 2 km ESE of Tierras Nuevas Poniente, Puerto Rico
  5. 2.1 4 km SSE of Cayey, 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.