QuakeIndex

Earthquake · reviewed by a seismologist

M 3.4md

Earthquake near Jobos, PR

No earthquake was likely felt in Jobos in the 24 hours to 10:50 am AST (14:50 UTC). The last one was M 3.0, 28 km (18 mi) WSW, at 7:09 pm AST on 5 November 2026, estimated intensity II (weak) in town. Every earthquake near Jobos

This page: a magnitude 3.4 earthquake was recorded 18 km (11 mi) south of Jobos, PR, at 6:33 pm AST on 20 July 2022 (22:33 UTC), 2.5 km deep. 1 person has reported feeling it to USGS.

USGS: 18 km S of Jobos, Puerto Rico

69 km (43 mi) S of San Juan, PR · 51 km (32 mi) SSW of Caguas, PR

6:33 pm AST, Jul 20, 2022 · · 2.5 km deep · released about 1.9 tons of TNT

Every earthquake near Jobos Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guayama Municipio 21 kmSalinas Municipio 21 kmArroyo Municipio 25 kmSanta Isabel Municipio 28 kmPatillas Municipio 31 kmCayey Municipio 35 kmMaunabo Municipio 38 kmAibonito Municipio 38 kmCoamo Municipio 39 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
6:33 pm AST on 20 July 2022 ()
Where
18 km (11 mi) south of Jobos, PR · earthquakes near Jobos
Magnitude
M 3.4 (md)
Depth
2.5 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Guayama Municipio, 21 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1506 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 58 km (36 mi) from the epicentre. In Jobos, 18 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: Guayama 22 km, intensity III · Santa Isabel 30 km, intensity II · Cayey 35 km, intensity II · Coamo 37 km, intensity II · Emajagua 39 km, intensity II · Río Cañas Abajo 40 km, intensity II · Jagual 46 km, intensity II · Sumidero 48 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 1.9 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 89,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 4,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 2,800× the energy of this one
  4. This earthquake M 3.4 about 1.9 tons of TNT
  5. Around the size people start to feel M 3.0 this one released 4× 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 4.6 on 2016-12-05 — about 63 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 17.7937, -66.1855. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guayama Municipio, PR 21 km (13 mi) NNE earthquakes near Guayama Municipio
Salinas Municipio, PR 21 km (13 mi) NNW earthquakes near Salinas Municipio
Arroyo Municipio, PR 25 km (16 mi) NE earthquakes near Arroyo Municipio
Santa Isabel Municipio, PR 28 km (17 mi) NW earthquakes near Santa Isabel Municipio
Patillas Municipio, PR 31 km (19 mi) NE earthquakes near Patillas Municipio
Cayey Municipio, PR 35 km (22 mi) N earthquakes near Cayey Municipio

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

Aftershocks so far

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

  1. 2.3 2 km SE of Lamboglia, Puerto Rico
  2. 2.3 3 km ESE of Salinas, Puerto Rico
  3. 3.0 6 km SSW of Potala Pastillo, Puerto Rico
  4. 1.9 2 km SSE of Lamboglia, Puerto Rico
  5. 2.4 Puerto Rico region
  6. 2.2 5 km SSW of Potala Pastillo, Puerto Rico
  7. 3.0 3 km ESE of Cayey, Puerto Rico
  8. 3.0 3 km E of Cayey, Puerto Rico
  9. 1.8 2 km SW of G. L. Garcia, Puerto Rico
  10. 2.1 3 km ENE of Mariano Colón, Puerto Rico
  11. 2.0 9 km S of Ponce, Puerto Rico
  12. 2.3 5 km SSW of Potala Pastillo, Puerto Rico
  13. 2.2 7 km S of Ponce, Puerto Rico
  14. 2.5 6 km NNW of Los Llanos, Puerto Rico
  15. 3.1 1 km E of Salinas, 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.