QuakeIndex

Earthquake · reviewed by a seismologist

M 1.7md

Earthquake near Mayagüez, PR

No earthquake was likely felt in Mayagüez in the 24 hours to 11:30 pm AST (03:30 UTC). The last one was M 2.9, 25 km (15 mi) SSE, at 3:17 am AST on 8 November 2026, estimated intensity II (weak) in town. Every earthquake near Mayagüez

This page: a magnitude 1.7 earthquake was recorded 30 km (19 mi) south-southeast of Mayagüez, PR, at 5:50 am AST on 22 January 2021 (09:50 UTC), 13 km deep.

USGS: Puerto Rico region

30 km (19 mi) SSE of Mayagüez, PR · 119 km (74 mi) WSW of San Juan, PR

5:50 am AST, Jan 22, 2021 · · 13 km deep · released about 10 lb of TNT

Every earthquake near Mayagüez Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lajas Municipio 6 kmCabo Rojo Municipio 13 kmGuánica Municipio 16 kmSan Germán Municipio 19 kmSabana Grande Municipio 21 kmHormigueros Municipio 22 kmYauco Municipio 28 kmMaricao Municipio 30 kmGuayanilla 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
5:50 am AST on 22 January 2021 ()
Where
30 km (19 mi) south-southeast of Mayagüez, PR · earthquakes near Mayagüez
Magnitude
M 1.7 (md)
Depth
13 km below the surface
Felt
no reports yet
Nearest
Lajas Municipio, 6 km NE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1835 days ago

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

At this magnitude and depth it was probably too small to be felt, even directly above it. In Mayagüez, 30 km away, the estimate is intensity I (not felt). 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: La Parguera, Palmarejo, Lajas, Pole Ojea, Boquerón, San Germán.

How big was it?

This earthquake released about 10 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,500,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 92× the energy of this one
  4. This earthquake M 1.7 about 10 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 12,000,000 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 17.9386, -67.0730. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lajas Municipio, PR 6 km (4 mi) NE earthquakes near Lajas Municipio
Cabo Rojo Municipio, PR 13 km (8 mi) WNW earthquakes near Cabo Rojo Municipio
Guánica Municipio, PR 16 km (10 mi) E earthquakes near Guánica Municipio
San Germán Municipio, PR 19 km (12 mi) NNE earthquakes near San Germán Municipio
Sabana Grande Municipio, PR 21 km (13 mi) NE earthquakes near Sabana Grande Municipio
Hormigueros Municipio, PR 22 km (14 mi) NNW earthquakes near Hormigueros Municipio

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

Aftershocks so far

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

  1. 2.7 2 km SW of Guánica, Puerto Rico
  2. 2.3 2 km ESE of La Parguera, Puerto Rico
  3. 2.3 Puerto Rico region
  4. 2.0 5 km SE of Maria Antonia, Puerto Rico
  5. 1.7 5 km ESE of La Parguera, Puerto Rico
  6. 2.3 3 km SW of Guánica, Puerto Rico
  7. 1.7 1 km NNW of Maria Antonia, Puerto Rico
  8. 2.2 1 km N of Guayanilla, Puerto Rico
  9. 1.7 0 km W of Indios, Puerto Rico
  10. 1.7 3 km NNW of Yauco, Puerto Rico
  11. 1.6 Puerto Rico region
  12. 1.8 6 km WSW of Fuig, Puerto Rico
  13. 2.3 18 km S of Guánica, Puerto Rico
  14. 1.8 4 km W of Fuig, Puerto Rico
  15. 2.8 6 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.