QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5ml

3 km NNW of Killingworth, Connecticut

· 5.5 km deep · released about 5.4 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Lower Connecticut River Valley Planning Region 8 kmSouth Central Connecticut Planning Region 24 kmSoutheastern Connecticut Planning Region 41 kmNaugatuck Valley Planning Region 44 kmCapitol Planning Region 47 kmSuffolk County 51 kmGreater Bridgeport Planning Region 57 kmNortheastern Connecticut Planning Region 71 kmWestern Connecticut Planning Region 73 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 1.5 (ml)
Depth
5.5 km below the surface
Felt
7 reports · strongest reported intensity III
Nearest
Lower Connecticut River Valley Planning Region, 8 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 470 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 7 people have reported feeling it to USGS.

How big was it?

This earthquake released about 5.4 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.5 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 2,800,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 2,000,000× the energy of this one
  3. Around the size people start to feel M 3.0 180× the energy of this one
  4. This earthquake M 1.5 about 5.4 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.

Where

Epicentre 41.3903, -72.5826. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Lower Connecticut River Valley Planning Region, CT 8 km (5 mi) WSW of here earthquakes near Lower Connecticut River Valley Planning Region
South Central Connecticut Planning Region, CT 24 km (15 mi) ENE of here earthquakes near South Central Connecticut Planning Region
Southeastern Connecticut Planning Region, CT 41 km (26 mi) WSW of here earthquakes near Southeastern Connecticut Planning Region
Naugatuck Valley Planning Region, CT 44 km (28 mi) ESE of here earthquakes near Naugatuck Valley Planning Region
Capitol Planning Region, CT 47 km (29 mi) S of here earthquakes near Capitol Planning Region
Suffolk County, NY 51 km (31 mi) N of here earthquakes near Suffolk County

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

Aftershocks so far

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

  1. 1.5 2 km SSW of Deep River Center, Connecticut
  2. 1.9 2 km NNE of East Haddam, Connecticut
  3. 2.2 1 km S of Moodus, Connecticut
  4. 1.8 2 km W of Conning Towers-Nautilus Park, Connecticut
  5. 1.9 2 km N of East Haddam, Connecticut
  6. 2.0 3 km E of Plainville, Connecticut
  7. 1.8 1 km NNW of Essex Village, Connecticut

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.