QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3mb_lg

3 km NNE of Antrim, New Hampshire

· 5.1 km deep · released about 85 lb of TNT

Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Hillsborough County 23 kmCheshire County 31 kmMerrimack County 33 kmSullivan County 41 kmBelknap County 65 kmWindham County 65 kmRockingham County 67 kmFranklin County 76 kmStrafford County 76 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 2.3 (mb_lg)
Depth
5.1 km below the surface
Felt
35 reports · strongest reported intensity IV
Nearest
Hillsborough County, 23 km SE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1437 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 35 people have reported feeling it to USGS.

How big was it?

This earthquake released about 85 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 180,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 130,000× the energy of this one
  3. Around the size people start to feel M 3.0 11× the energy of this one
  4. This earthquake M 2.3 about 85 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 43.0630, -71.9224. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Hillsborough County, NH 23 km (15 mi) NW of here earthquakes near Hillsborough County
Cheshire County, NH 31 km (19 mi) ENE of here earthquakes near Cheshire County
Merrimack County, NH 33 km (20 mi) SW of here earthquakes near Merrimack County
Sullivan County, NH 41 km (26 mi) SE of here earthquakes near Sullivan County
Belknap County, NH 65 km (40 mi) SW of here earthquakes near Belknap County
Windham County, VT 65 km (41 mi) E of here earthquakes near Windham County

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

Aftershocks so far

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

  1. 1.5 2 km S of Bedford, New Hampshire
  2. 2.1 2 km NNW of Milford, New Hampshire
  3. 1.9 2 km N of Webster, New Hampshire
  4. 1.9 4 km ESE of Northfield, New Hampshire
  5. 1.5 5 km SSE of Boscawen, New Hampshire
  6. 1.6 2 km S of Henniker, New Hampshire
  7. 1.7 3 km SW of Townsend, Massachusetts
  8. 2.0 2 km WNW of Loudon, New Hampshire
  9. 2.7 5 km SW of Chichester, New Hampshire
  10. 2.2 1 km W of Andover, New Hampshire
  11. 2.1 4 km SE of Warner, New Hampshire
  12. 1.9 0 km SW of Bow Bog, New Hampshire

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.