QuakeIndex

Earthquake · reviewed by a seismologist

M 4.6ml

75 km NW of San Antonio, Puerto Rico

Yes. A magnitude 4.6 earthquake was recorded 75 km NW of San Antonio, Puerto Rico, at 10:27 am AST on 29 January 2020 (14:27 UTC), 7.0 km deep. 133 people have reported feeling it to USGS.

· 7.0 km deep · released about 120 tons of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Aguadilla Municipio 73 kmRincón Municipio 79 kmAguada Municipio 79 kmIsabela Municipio 83 kmMoca Municipio 86 kmAñasco Municipio 91 kmQuebradillas Municipio 92 kmSan Sebastián Municipio 98 kmCamuy Municipio 98 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
Magnitude
M 4.6 (ml)
Depth
7.0 km below the surface
Felt
133 reports · strongest reported intensity IV
Nearest
Aguadilla Municipio, 73 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2398 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon.

At this magnitude and depth, people at rest would likely notice it out to about 149 km (93 mi) from the epicentre. 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.

How big was it?

This earthquake released about 120 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.6 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 1,400× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 63× the energy of this one
  3. Magna, Utah 2020 M 5.7 45× the energy of this one
  4. This earthquake M 4.6 about 120 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 250× 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 6.0 on 2019-09-24 — about 130 times the energy of this one.

Before 2016, the USGS record lists 16 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 94 km NE of Punta Cana, Dominican Republic · 22 km NNW of this epicentre
  2. 6.4 32 km NW of Aguadilla, Puerto Rico · 45 km SE of this epicentre
  3. 6.1 80 km NE of Punta Cana, Dominican Republic · 34 km NW of this epicentre
  4. 6.0 67 km NNW of San Antonio, Puerto Rico · 42 km ENE of this epicentre
  5. 5.8 33 km NW of San Antonio, Puerto Rico · 42 km SE 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 18.9538, -67.6276. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Aguadilla Municipio, PR 73 km (46 mi) SE earthquakes near Aguadilla Municipio
Rincón Municipio, PR 79 km (49 mi) SSE earthquakes near Rincón Municipio
Aguada Municipio, PR 79 km (49 mi) SE earthquakes near Aguada Municipio
Isabela Municipio, PR 83 km (52 mi) SE earthquakes near Isabela Municipio
Moca Municipio, PR 86 km (54 mi) SE earthquakes near Moca Municipio
Añasco Municipio, PR 91 km (56 mi) SE earthquakes near Añasco Municipio

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

Aftershocks so far

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

  1. 3.2 82 km NW of San Antonio, Puerto Rico
  2. 2.7 Mona Passage
  3. 3.0 66 km NW of San Antonio, Puerto Rico
  4. 2.6 73 km NE of Punta Cana, Dominican Republic
  5. 2.2 61 km NE of Punta Cana, Dominican Republic
  6. 3.4 77 km NE of Punta Cana, Dominican Republic
  7. 3.1 96 km NNW of San Antonio, Puerto Rico
  8. 2.8 57 km NW of Rincón, Puerto Rico
  9. 2.4 50 km NE of Punta Cana, Dominican Republic
  10. 3.0 77 km NE of Punta Cana, Dominican Republic
  11. 3.0 69 km NW of Rincón, Puerto Rico
  12. 3.2 75 km NW of San Antonio, Puerto Rico
  13. 3.0 88 km NE of Punta Cana, Dominican Republic
  14. 3.1 75 km NW of San Antonio, Puerto Rico
  15. 2.1 Mona Passage

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.