QuakeIndex

Earthquake · reviewed by a seismologist

M 1.5md

Earthquake near Ridgely, TN

No earthquake was likely felt in Ridgely in the 24 hours to 4:54 pm CST (22:54 UTC). The last one was M 1.6, 3 km (2 mi) NNE, at 9:02 pm CDT on 31 October 2026, estimated intensity II (weak) in town. Every earthquake near Ridgely

This page: a magnitude 1.5 earthquake was recorded 4 km (3 mi) southwest of Ridgely, TN, at 2:31 am CDT on 6 August 2020 (07:31 UTC), 7.7 km deep.

USGS: 4 km SW of Ridgely, Tennessee

2:31 am CDT, Aug 6, 2020 · · 7.7 km deep · released about 5.6 lb of TNT

10 km30 km60 km120 km N Lake County 12 kmDyer County 23 kmPemiscot County 24 kmObion County 36 kmNew Madrid County 42 kmFulton County 46 kmDunklin County 50 kmLauderdale County 53 kmCrockett County 58 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
2:31 am CDT on 6 August 2020 ()
Where
4 km (3 mi) southwest of Ridgely, TN · earthquakes near Ridgely
Magnitude
M 1.5 (md)
Depth
7.7 km below the surface
Felt
no reports yet
Nearest
Lake County, 12 km NNE
Nearest mapped fault
Reelfoot scarp and New Madrid seismic zone, under 1 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2288 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Ridgely, 4 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Earthquakes near other towns within 30 km: Caruthersville, Tiptonville, Hayti, Dyersburg, Newbern, Portageville.

How big was it?

This earthquake released about 5.6 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 2,700,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 1,900,000× the energy of this one
  3. Around the size people start to feel M 3.0 170× the energy of this one
  4. This earthquake M 1.5 about 5.6 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 since 1900 lists no earthquake of M5 or more within 50 km.

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 36.2325, -89.5175. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, TN 12 km (7 mi) NNE earthquakes near Lake County
Dyer County, TN 23 km (14 mi) SSE earthquakes near Dyer County
Pemiscot County, MO 24 km (15 mi) W earthquakes near Pemiscot County
Obion County, TN 36 km (22 mi) ENE earthquakes near Obion County
New Madrid County, MO 42 km (26 mi) NNW earthquakes near New Madrid County
Fulton County, KY 46 km (29 mi) NE earthquakes near Fulton County

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

Aftershocks so far

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

  1. 2.0 6 km E of Ridgely, Tennessee
  2. 2.1 2 km NE of Marston, Missouri
  3. 1.8 2 km NE of Marston, Missouri
  4. 1.9 5 km WSW of Tiptonville, Tennessee
  5. 1.6 10 km NNW of Tiptonville, Tennessee
  6. 1.5 southeastern Missouri
  7. 2.0 6 km E of Ridgely, Tennessee
  8. 1.6 5 km SSW of Tiptonville, Tennessee
  9. 2.1 2 km NNE of Cooter, Missouri
  10. 1.7 3 km E of Marston, Missouri
  11. 1.6 4 km NW of Marston, Missouri
  12. 2.3 3 km W of Ridgely, Tennessee
  13. 1.6 6 km S of Ridgely, Tennessee
  14. 2.2 9 km ENE of Steele, Missouri
  15. 1.8 9 km SW of Caruthersville, Missouri

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.