QuakeIndex

Earthquake · reviewed by a seismologist

M 3.1mb_lg

3 km WSW of Marlboro, New Jersey

· 5.6 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N Monmouth County 12 kmMiddlesex County 18 kmRichmond County 31 kmMercer County 35 kmUnion County 40 kmSomerset County 41 kmKings County 47 kmOcean County 49 kmHudson County 51 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 3.1 (mb_lg)
Depth
5.6 km below the surface
Felt
4459 reports · strongest reported intensity V
Measured shaking
intensity IV (ShakeMap)
USGS impact alert
green
Nearest
Monmouth County, 12 km E
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 905 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 4459 people have reported feeling it to USGS.

How big was it?

This earthquake released about 1,300 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 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× 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.

Where

Epicentre 40.3023, -74.2892. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Monmouth County, NJ 12 km (7 mi) W of here earthquakes near Monmouth County
Middlesex County, NJ 18 km (11 mi) SSE of here earthquakes near Middlesex County
Richmond County, NY 31 km (20 mi) SSW of here earthquakes near Richmond County
Mercer County, NJ 35 km (22 mi) E of here earthquakes near Mercer County
Union County, NJ 40 km (25 mi) S of here earthquakes near Union County
Somerset County, NJ 41 km (25 mi) SE of here earthquakes near Somerset County

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

Aftershocks so far

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

  1. 2.1 1 km N of Deal, New Jersey
  2. 1.9 1 km WSW of Martinsville, New Jersey

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.