QuakeIndex

Earthquake · reviewed by a seismologist

M 2.1md

Earthquake near Sparta, NC

USGS: 4 km SSE of Sparta, North Carolina

8:20 pm EDT, Aug 11, 2020 · · 1.7 km deep · released about 51 lb of TNT

Every earthquake near Sparta Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Alleghany County 3 kmGrayson County 23 kmGalax city 28 kmWilkes County 29 kmAshe County 35 kmSurry County 38 kmCarroll County 45 kmWythe County 48 kmYadkin County 53 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
8:20 pm EDT on 11 August 2020 ()
Where
5 km (3 mi) SSE of Sparta, NC · earthquakes near Sparta
Magnitude
M 2.1 (md)
Depth
1.7 km below the surface
Felt
32 reports · strongest reported intensity III
Nearest
Alleghany County, 3 km NW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2169 days ago

A magnitude 2.1 earthquake was recorded 5 km (3 mi) SSE of Sparta, NC, at 8:20 pm EDT on 11 August 2020 (00:20 UTC). 32 people have reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

Earthquakes near other towns within 30 km: Thurmond, Hays, Mulberry, Galax, Fairplains.

How big was it?

This earthquake released about 51 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.1 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 300,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 210,000× the energy of this one
  3. Around the size people start to feel M 3.0 19× the energy of this one
  4. This earthquake M 2.1 about 51 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

The largest earthquake within 50 km since 2016 was M 5.1 on 2020-08-09 — about 27,000 times the energy of this one.

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 36.4657, -81.1108. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Alleghany County, NC 3 km (2 mi) NW earthquakes near Alleghany County
Grayson County, VA 23 km (14 mi) NNW earthquakes near Grayson County
Galax city, VA 28 km (18 mi) NE earthquakes near Galax city
Wilkes County, NC 29 km (18 mi) S earthquakes near Wilkes County
Ashe County, NC 35 km (22 mi) W earthquakes near Ashe County
Surry County, NC 38 km (24 mi) E earthquakes near Surry County

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

Aftershocks so far

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

  1. 2.2 9 km ESE of Independence, Virginia
  2. 2.2 7 km SSE of Sparta, North Carolina
  3. 2.1 4 km WSW of Lowgap, North Carolina
  4. 2.2 16 km E of Jefferson, North Carolina
  5. 2.0 8 km S of Sparta, North Carolina
  6. 2.2 7 km SSE of Sparta, North Carolina
  7. 2.2 6 km SSE of Sparta, North Carolina
  8. 2.1 1 km ESE of Sparta, North Carolina
  9. 2.3 5 km SE of Sparta, North Carolina
  10. 2.3 2 km E of Sparta, North Carolina
  11. 1.5 8 km W of Lowgap, North Carolina
  12. 2.3 8 km W of Lowgap, North Carolina
  13. 2.6 Virginia-North Carolina border region
  14. 2.7 5 km S of Hillsville, Virginia
  15. 1.8 9 km SSE of West Jefferson, North Carolina

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.