QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1md

12 km SE of Emajagua, Puerto Rico

· 15 km deep · released about 1,200 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Maunabo Municipio 14 kmYabucoa Municipio 17 kmPatillas Municipio 22 kmHumacao Municipio 24 kmArroyo Municipio 27 kmLas Piedras Municipio 30 kmSan Lorenzo Municipio 32 kmNaguabo Municipio 32 kmJuncos Municipio 36 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 3.1 (md)
Depth
15 km below the surface
Felt
no reports yet
Nearest
Maunabo Municipio, 14 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 8 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 1,200 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 290,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 13,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 9,100× the energy of this one
  4. This earthquake M 3.1 about 1,200 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.2× 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.

Where

Epicentre 17.9238, -65.7922. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Maunabo Municipio, PR 14 km (9 mi) SE of here earthquakes near Maunabo Municipio
Yabucoa Municipio, PR 17 km (10 mi) SSE of here earthquakes near Yabucoa Municipio
Patillas Municipio, PR 22 km (14 mi) ESE of here earthquakes near Patillas Municipio
Humacao Municipio, PR 24 km (15 mi) S of here earthquakes near Humacao Municipio
Arroyo Municipio, PR 27 km (17 mi) ESE of here earthquakes near Arroyo Municipio
Las Piedras Municipio, PR 30 km (19 mi) SSE of here earthquakes near Las Piedras Municipio

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

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

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.

For this area

The largest earthquake within 50 km in our catalogue was M 4.8 on 2021-10-08 — it released about 410 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.