QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

2 km W of Salem, New Hampshire

· 1.7 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N Rockingham County 24 kmEssex County 34 kmMiddlesex County 37 kmHillsborough County 43 kmSuffolk County 53 kmStrafford County 58 kmMerrimack County 68 kmNorfolk County 69 kmWorcester County 79 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 1.8 (ml)
Depth
1.7 km below the surface
Felt
27 reports · strongest reported intensity IV
Nearest
Rockingham County, 24 km NNE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2417 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 27 people have reported feeling it to USGS.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 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 42.7892, -71.2257. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Rockingham County, NH 24 km (15 mi) SSW of here earthquakes near Rockingham County
Essex County, MA 34 km (21 mi) WNW of here earthquakes near Essex County
Middlesex County, MA 37 km (23 mi) NNE of here earthquakes near Middlesex County
Hillsborough County, NH 43 km (27 mi) ESE of here earthquakes near Hillsborough County
Suffolk County, MA 53 km (33 mi) NNW of here earthquakes near Suffolk County
Strafford County, NH 58 km (36 mi) SSW of here earthquakes near Strafford County

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

Aftershocks so far

9 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. 1.7 2 km NE of Danville, New Hampshire
  4. 1.6 3 km SSE of Greenland, New Hampshire
  5. 1.7 3 km SW of Townsend, Massachusetts
  6. 1.9 0 km SW of Bow Bog, New Hampshire
  7. 1.8 1 km S of Boxborough, Massachusetts
  8. 1.9 1 km SSW of Rye, New Hampshire
  9. 1.9 6 km E of Weare, 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.