QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near San Juan, PR

No earthquake was likely felt in San Juan in the 24 hours to 11:23 am AST (15:23 UTC). The last one was M 4.1, 99 km (62 mi) SE, at 5:44 am AST on 28 October 2026, estimated intensity II (weak) in town; 5 felt reports to USGS. Every earthquake near San Juan

This page: a magnitude 2.1 earthquake was recorded 47 km (29 mi) southwest of San Juan, PR, at 8:12 pm AST on 1 September 2023 (00:12 UTC), 2.8 km deep.

USGS: Puerto Rico region

47 km (29 mi) SW of San Juan, PR · 28 km (17 mi) NE of Ponce, PR

8:12 pm AST, Sep 1, 2023 · · 2.8 km deep · released about 49 lb of TNT

Every earthquake near San Juan Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Orocovis Municipio 5 kmVillalba Municipio 6 kmCoamo Municipio 11 kmBarranquitas Municipio 13 kmMorovis Municipio 16 kmCiales Municipio 17 kmJayuya Municipio 17 kmAibonito Municipio 18 kmCorozal 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
8:12 pm AST on 1 September 2023 ()
Where
47 km (29 mi) southwest of San Juan, PR · earthquakes near San Juan
Magnitude
M 2.1 (md)
Depth
2.8 km below the surface
Felt
no reports yet
Nearest
Orocovis Municipio, 5 km N
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1167 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth, people at rest would likely notice it out to about 18 km (11 mi) from the epicentre. In San Juan, 47 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.

Likely felt in: Coamo 12 km, intensity II · Río Cañas Abajo 15 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 49 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 5.8 310,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 220,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 49 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 in our catalogue was M 6.4 on 2020-01-07 — about 2,500,000 times the energy of this one.

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 18.1700, -66.4288. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Orocovis Municipio, PR 5 km (3 mi) N earthquakes near Orocovis Municipio
Villalba Municipio, PR 6 km (4 mi) SW earthquakes near Villalba Municipio
Coamo Municipio, PR 11 km (7 mi) SE earthquakes near Coamo Municipio
Barranquitas Municipio, PR 13 km (8 mi) ENE earthquakes near Barranquitas Municipio
Morovis Municipio, PR 16 km (10 mi) N earthquakes near Morovis Municipio
Ciales Municipio, PR 17 km (10 mi) NNW earthquakes near Ciales Municipio

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

Aftershocks so far

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

  1. 2.5 Puerto Rico region
  2. 2.6 Puerto Rico region
  3. 2.7 4 km S of Salinas, Puerto Rico
  4. 2.3 4 km SSE of Salinas, Puerto Rico
  5. 2.7 1 km SSW of Magas Arriba, Puerto Rico
  6. 1.9 Puerto Rico region
  7. 2.3 1 km SSW of Ponce, Puerto Rico
  8. 2.4 0 km WSW of Ponce, Puerto Rico
  9. 2.5 3 km SW of Indios, Puerto Rico
  10. 2.1 2 km WNW of Guayanilla, Puerto Rico
  11. 2.5 2 km E of Yauco, Puerto Rico
  12. 3.3 Puerto Rico region
  13. 2.5 5 km SSE of Indios, Puerto Rico
  14. 2.4 1 km N of Indios, Puerto Rico
  15. 2.5 1 km WNW of Indios, 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.