QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8md

Earthquake near Ridgely, TN

No earthquake was likely felt in Ridgely in the 24 hours to 8:08 am CST (14:08 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 1.8 earthquake was recorded 6 km (4 mi) southeast of Ridgely, TN, at 11:50 pm CDT on 27 July 2018 (04:50 UTC), 9.1 km deep.

USGS: 5 km SE of Ridgely, Tennessee

11:50 pm CDT, Jul 27, 2018 · · 9.1 km deep · released about 13 lb of TNT

10 km30 km60 km120 km N Lake County 12 kmDyer County 20 kmObion County 30 kmPemiscot County 31 kmFulton County 42 kmNew Madrid County 45 kmGibson County 52 kmCrockett County 53 kmLauderdale County 55 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
11:50 pm CDT on 27 July 2018 ()
Where
6 km (4 mi) southeast of Ridgely, TN · earthquakes near Ridgely
Magnitude
M 1.8 (md)
Depth
9.1 km below the surface
Felt
no reports yet
Nearest
Lake County, 12 km NNW
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 3028 days ago

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

At this magnitude and depth, people at rest would likely notice it out to about 12 km (7 mi) from the epicentre. In Ridgely, 6 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: Tiptonville, Caruthersville, Newbern, Dyersburg, Obion, Troy.

How big was it?

This earthquake released about 13 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 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 810,000× the energy of this one
  3. Around the size people start to feel M 3.0 72× the energy of this one
  4. This earthquake M 1.8 about 13 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 36.2285, -89.4382. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Lake County, TN 12 km (8 mi) NNW earthquakes near Lake County
Dyer County, TN 20 km (12 mi) S earthquakes near Dyer County
Obion County, TN 30 km (19 mi) ENE earthquakes near Obion County
Pemiscot County, MO 31 km (19 mi) W earthquakes near Pemiscot County
Fulton County, KY 42 km (26 mi) NNE earthquakes near Fulton County
New Madrid County, MO 45 km (28 mi) NNW earthquakes near New Madrid 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. 1.5 3 km E of Ridgely, Tennessee
  2. 1.8 3 km ENE of Ridgely, Tennessee
  3. 2.4 7 km SE of Marston, Missouri
  4. 1.6 3 km ENE of Ridgely, Tennessee
  5. 2.3 3 km E of Steele, Missouri
  6. 2.0 2 km ESE of Ridgely, Tennessee
  7. 2.1 2 km NW of Marston, Missouri
  8. 1.9 3 km E of Ridgely, Tennessee
  9. 1.7 3 km ENE of Ridgely, Tennessee
  10. 1.7 2 km ENE of Caruthersville, Missouri
  11. 1.6 3 km NE of Caruthersville, Missouri
  12. 1.6 3 km ENE of Ridgely, Tennessee
  13. 1.9 7 km S of Catron, Missouri
  14. 1.6 3 km ENE of Ridgely, Tennessee
  15. 2.1 3 km E of Ridgely, Tennessee

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.