QuakeIndex

Earthquake · reviewed by a seismologist

M 2.2md

Earthquake near Garrochales, PR

No earthquake was likely felt in Garrochales in the 24 hours to 1:38 am AST (05:38 UTC). The last one was M 2.9, 12 km (7 mi) NW, at 2:05 am AST on 13 October 2026, estimated intensity II (weak) in town. Every earthquake near Garrochales

This page: a magnitude 2.2 earthquake was recorded 18 km (11 mi) north-northwest of Garrochales, PR, at 1:30 pm AST on 21 September 2018 (17:30 UTC), 33 km deep.

USGS: 17 km NNW of Garrochales, Puerto Rico

62 km (38 mi) WNW of San Juan, PR · 22 km (13 mi) NE of Arecibo, PR

1:30 pm AST, Sep 21, 2018 · · 33 km deep · released about 69 lb of TNT

Every earthquake near Garrochales Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Barceloneta Municipio 16 kmArecibo Municipio 20 kmManatí Municipio 22 kmFlorida Municipio 27 kmHatillo Municipio 27 kmVega Baja Municipio 28 kmCamuy Municipio 32 kmVega Alta Municipio 34 kmCiales Municipio 36 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
1:30 pm AST on 21 September 2018 ()
Where
18 km (11 mi) north-northwest of Garrochales, PR · earthquakes near Garrochales
Magnitude
M 2.2 (md)
Depth
33 km below the surface
Felt
no reports yet
Nearest
Barceloneta Municipio, 16 km SSE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2973 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 Garrochales, 18 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: Animas, Arecibo, Barceloneta, Sabana Hoyos, Imbery, La Luisa.

How big was it?

This earthquake released about 69 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.2 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 220,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 150,000× the energy of this one
  3. Around the size people start to feel M 3.0 14× the energy of this one
  4. This earthquake M 2.2 about 69 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 4.8 on 2017-08-18 — about 6,900 times the energy of this one.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.8 12 km N of Garrochales, Puerto Rico · 7 km SE of this epicentre
  2. 5.0 3 km N of Brenas, Puerto Rico · 31 km ESE 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 18.6068, -66.6086. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Barceloneta Municipio, PR 16 km (10 mi) SSE earthquakes near Barceloneta Municipio
Arecibo Municipio, PR 20 km (13 mi) SSW earthquakes near Arecibo Municipio
Manatí Municipio, PR 22 km (14 mi) SE earthquakes near Manatí Municipio
Florida Municipio, PR 27 km (17 mi) S earthquakes near Florida Municipio
Hatillo Municipio, PR 27 km (17 mi) SW earthquakes near Hatillo Municipio
Vega Baja Municipio, PR 28 km (17 mi) SE earthquakes near Vega Baja Municipio

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

Aftershocks so far

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

  1. 2.8 40 km N of Brenas, Puerto Rico
  2. 2.1 21 km NNE of Isabela, Puerto Rico
  3. 2.5 6 km N of Isabela, Puerto Rico
  4. 2.1 15 km NNE of Isabela, Puerto Rico
  5. 2.8 Puerto Rico region
  6. 2.5 51 km N of Hatillo, Puerto Rico
  7. 2.6 Puerto Rico region
  8. 2.5 Puerto Rico region
  9. 2.8 Puerto Rico region
  10. 2.9 61 km N of Tierras Nuevas Poniente, Puerto Rico
  11. 2.3 23 km NNE of Isabela, Puerto Rico
  12. 2.9 65 km NNE of Arecibo, Puerto Rico
  13. 1.9 5 km NW of Adjuntas, Puerto Rico
  14. 2.5 55 km N of Tierras Nuevas Poniente, Puerto Rico
  15. 2.8 61 km N of Tierras Nuevas Poniente, 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.