QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Potsdam, NY

USGS: 4 km S of Winthrop, New York

6:29 am EDT, Jun 15, 2021 · · 5.0 km deep · released about 15 lb of TNT

10 km30 km60 km120 km N St. Lawrence County 38 kmFranklin County 42 kmClinton County 85 kmEssex County 108 kmGrand Isle County 117 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
6:29 am EDT on 15 June 2021 ()
Where
18 km (11 mi) ENE of Potsdam, NY · earthquakes near Potsdam
Magnitude
M 1.8 (ml)
Depth
5.0 km below the surface
Felt
no reports yet
Nearest
St. Lawrence County, 38 km SW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1863 days ago

A magnitude 1.8 earthquake was recorded 18 km (11 mi) ENE of Potsdam, NY, at 6:29 am EDT on 15 June 2021 (10:29 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Norwood, Norfolk, Massena, Hannawa Falls.

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.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 2 earthquakes of M5 or more within 50 km:

  1. 5.7 The 1944 Massena, New York Earthquake · 21 km N of this epicentre
  2. 5.1 Near Cornwall, Ontario, Canada · 32 km NNW of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 44.7578, -74.7858. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
St. Lawrence County, NY 38 km (23 mi) SW earthquakes near St. Lawrence County
Franklin County, NY 42 km (26 mi) ESE earthquakes near Franklin County
Clinton County, NY 85 km (53 mi) E earthquakes near Clinton County
Essex County, NY 108 km (67 mi) SE earthquakes near Essex County
Grand Isle County, VT 117 km (73 mi) E earthquakes near Grand Isle County
Lewis County, NY 120 km (75 mi) SSW earthquakes near Lewis County

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

Aftershocks so far

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

  1. 2.0 7 km NE of Potsdam, New York
  2. 1.6 5 km S of Fort Covington Hamlet, New York
  3. 1.6 6 km ESE of Fort Covington Hamlet, New York
  4. 1.6 1 km S of Massena, New York
  5. 2.2 8 km W of Saint Regis Falls, New York
  6. 2.5 6 km SSE of Fort Covington Hamlet, New York
  7. 1.6 16 km NNW of Tupper Lake, New York
  8. 1.6 8 km NNE of Rensselaer Falls, New York
  9. 2.8 8 km NNW of Canton, New York
  10. 1.9 8 km ESE of Fort Covington Hamlet, New York
  11. 1.6 Ontario-Quebec border region, Canada
  12. 2.1 7 km SW of Cornwall, Canada
  13. 2.2 9 km WNW of Massena, New York
  14. 1.7 New York
  15. 1.6 1 km SE of Saint Regis Falls, New York

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.