QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

Earthquake near Tallaboa, PR

No earthquake was likely felt in Tallaboa in the 24 hours to 3:24 am AST (07:24 UTC). The last one was M 2.1, 9 km (5 mi) WNW, at 4:39 pm AST on 9 November 2026, estimated intensity II (weak) in town. Every earthquake near Tallaboa

This page: a magnitude 3.4 earthquake was recorded 8 km (5 mi) southwest of Tallaboa, PR, at 8:48 pm AST on 21 January 2020 (00:48 UTC), 13 km deep. 9 people have reported feeling it to USGS.

USGS: 8 km SW of Tallaboa, Puerto Rico

16 km (10 mi) WSW of Ponce, PR

8:48 pm AST, Jan 21, 2020 · · 13 km deep · released about 1.7 tons of TNT

Every earthquake near Tallaboa Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guayanilla Municipio 9 kmPeñuelas Municipio 11 kmGuánica Municipio 17 kmPonce Municipio 18 kmYauco Municipio 20 kmSabana Grande Municipio 26 kmAdjuntas Municipio 27 kmJuana Díaz Municipio 29 kmLajas Municipio 30 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
8:48 pm AST on 21 January 2020 ()
Where
8 km (5 mi) southwest of Tallaboa, PR · earthquakes near Tallaboa
Magnitude
M 3.4 (md)
Depth
13 km below the surface
Felt
9 reports · strongest reported intensity IV
Nearest
Guayanilla Municipio, 9 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2406 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, people at rest would likely notice it out to about 54 km (34 mi) from the epicentre. In Tallaboa, 8 km away, the estimate is intensity III (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: Tallaboa 8 km, intensity III · Magas Arriba 9 km, intensity III · Guayanilla 10 km, intensity III · Tallaboa Alta 14 km, intensity III · Yauco 15 km, intensity III · Ponce 17 km, intensity III · Adjuntas 26 km, intensity II · Río Cañas Abajo 33 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1.7 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.4 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 99,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,400× the energy of this one
  3. Magna, Utah 2020 M 5.7 3,100× the energy of this one
  4. This earthquake M 3.4 about 1.7 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 3.6× 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 6.4 on 2020-01-07 — about 35,000 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 17.9361, -66.7605. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guayanilla Municipio, PR 9 km (5 mi) NNW earthquakes near Guayanilla Municipio
Peñuelas Municipio, PR 11 km (7 mi) NNE earthquakes near Peñuelas Municipio
Guánica Municipio, PR 17 km (11 mi) W earthquakes near Guánica Municipio
Ponce Municipio, PR 18 km (11 mi) ENE earthquakes near Ponce Municipio
Yauco Municipio, PR 20 km (12 mi) NNW earthquakes near Yauco Municipio
Sabana Grande Municipio, PR 26 km (16 mi) NW earthquakes near Sabana Grande Municipio

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

Aftershocks so far

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

  1. 2.7 8 km SSE of Indios, Puerto Rico
  2. 2.2 9 km SE of Maria Antonia, Puerto Rico
  3. 2.7 10 km S of Ponce, Puerto Rico
  4. 2.7 10 km S of Ponce, Puerto Rico
  5. 3.1 12 km SSE of Maria Antonia, Puerto Rico
  6. 3.0 3 km WSW of Tallaboa, Puerto Rico
  7. 2.6 12 km SSE of Maria Antonia, Puerto Rico
  8. 2.5 15 km SSE of Guánica, Puerto Rico
  9. 2.6 6 km SSE of Maria Antonia, Puerto Rico
  10. 2.1 9 km SSE of Maria Antonia, Puerto Rico
  11. 2.5 17 km SSE of Guánica, Puerto Rico
  12. 3.0 7 km SSE of La Parguera, Puerto Rico
  13. 3.1 15 km SSE of Guánica, Puerto Rico
  14. 2.2 3 km SSW of Tallaboa, Puerto Rico
  15. 2.8 7 km SW of Guánica, 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.