QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

Earthquake near Seymour, TN

USGS: 6 km W of Seymour, Tennessee

16 km (10 mi) ESE of Knoxville, TN

2:22 am EDT, May 20, 2018 · · 16 km deep · released about 91 lb of TNT

10 km30 km60 km120 km N Knox County 17 kmBlount County 25 kmSevier County 27 kmJefferson County 37 kmAnderson County 44 kmUnion County 44 kmSwain County 47 kmLoudon County 50 kmGrainger County 50 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
2:22 am EDT on 20 May 2018 ()
Where
7 km (4 mi) W of Seymour, TN · earthquakes near Seymour
Magnitude
M 2.3 (md)
Depth
16 km below the surface
Felt
no reports yet
Nearest
Knox County, 17 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 3058 days ago

A magnitude 2.3 earthquake was recorded 7 km (4 mi) W of Seymour, TN, at 2:22 am EDT on 20 May 2018 (06:22 UTC). This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Wildwood, Knoxville, Eagleton Village, Alcoa, Mascot, Sevierville.

How big was it?

This earthquake released about 91 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 5.8 170,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 120,000× the energy of this one
  3. Around the size people start to feel M 3.0 10× the energy of this one
  4. This earthquake M 2.3 about 91 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 35.8897, -83.7968. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Knox County, TN 17 km (11 mi) NW earthquakes near Knox County
Blount County, TN 25 km (16 mi) SSW earthquakes near Blount County
Sevier County, TN 27 km (17 mi) ESE earthquakes near Sevier County
Jefferson County, TN 37 km (23 mi) ENE earthquakes near Jefferson County
Anderson County, TN 44 km (27 mi) NW earthquakes near Anderson County
Union County, TN 44 km (27 mi) N earthquakes near Union County

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

Aftershocks so far

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

  1. 1.7 5 km WNW of Sevierville, Tennessee
  2. 2.2 5 km W of Sevierville, Tennessee
  3. 2.1 9 km ESE of Vonore, Tennessee
  4. 2.0 11 km ESE of Vonore, Tennessee
  5. 2.6 2 km SSE of Mascot, Tennessee
  6. 2.1 2 km W of Alcoa, Tennessee
  7. 1.6 3 km SSE of Garland, Tennessee
  8. 1.9 4 km SSE of Garland, Tennessee
  9. 1.9 10 km ESE of Vonore, Tennessee
  10. 2.0 2 km WNW of Greenback, Tennessee
  11. 1.6 7 km ESE of Vonore, Tennessee
  12. 2.3 1 km ENE of Maryville, Tennessee
  13. 2.4 7 km SW of Mascot, Tennessee
  14. 2.6 7 km WNW of Farragut, Tennessee
  15. 1.9 4 km SSW of Maryville, 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.