Earthquake · reviewed by a seismologist
M 2.4md
Earthquake near Unicoi, TN
No earthquake was likely felt in Unicoi in the 24 hours to 7:30 am EST (12:30 UTC). The last one was M 4.1, 164 km (102 mi) WSW, at 9:04 am EDT on 10 May 2025, estimated intensity III (weak) in town; 45,935 felt reports to USGS. Every earthquake near Unicoi
This page: a magnitude 2.4 earthquake was recorded 5 km (3 mi) east-southeast of Unicoi, TN, at 3:45 pm EDT on 28 March 2018 (19:45 UTC), 2.5 km deep.
USGS: 5 km ESE of Unicoi, Tennessee
20 km (13 mi) SSE of Johnson City, TN · 150 km (93 mi) E of Knoxville, TN
- When
- 3:45 pm EDT on 28 March 2018 ()
- Where
- 5 km (3 mi) east-southeast of Unicoi, TN · earthquakes near Unicoi
- Magnitude
- M 2.4 (md)
- Depth
- 2.5 km below the surface
- Felt
- no reports yet
- Nearest
- Unicoi County, 13 km SW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3149 days ago
Earthquake alerts for Unicoi, TN
Get a notification in this browser when USGS records an earthquake near Unicoi, TN. No account or email needed.
Alerts are on for .
Not a warning. An alert comes after USGS publishes a quake, usually minutes after the shaking. For early warning use ShakeAlert, through your phone's Wireless Emergency Alerts or the MyShake app.
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 39 km (24 mi) from the epicentre. In Unicoi, 5 km away, the estimate is intensity III (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: Erwin, Banner Hill, Johnson City, Midway, Jonesborough, Roan Mountain.
How big was it?
This earthquake released about 100 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.4 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 150,000× the energy of this one
- Magna, Utah 2020 M 5.7 110,000× the energy of this one
- Around the size people start to feel M 3.0 9.4× the energy of this one
- This earthquake M 2.4 about 100 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 36.1728, -82.2995. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Unicoi County, TN | 13 km (8 mi) | SW | earthquakes near Unicoi County |
| Carter County, TN | 20 km (12 mi) | NE | earthquakes near Carter County |
| Mitchell County, NC | 22 km (13 mi) | SE | earthquakes near Mitchell County |
| Washington County, TN | 22 km (14 mi) | NW | earthquakes near Washington County |
| Yancey County, NC | 32 km (20 mi) | S | earthquakes near Yancey County |
| Avery County, NC | 36 km (22 mi) | ESE | earthquakes near Avery County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
21 earthquakes have been recorded within 50 km since this one.
- 1.7 6 km WSW of Newland, North Carolina
- 2.3 2 km ENE of Greeneville, Tennessee
- 1.8 8 km W of Bakersville, North Carolina
- 1.9 1 km SW of Fall Branch, Tennessee
- 2.2 8 km WNW of Roan Mountain, Tennessee
- 1.8 12 km N of Old Fort, North Carolina
- 2.0 7 km N of Spruce Pine, North Carolina
- 1.8 9 km E of Bakersville, North Carolina
- 1.6 7 km SSW of Banner Hill, Tennessee
- 2.4 9 km SSW of Banner Hill, Tennessee
- 2.8 8 km SW of Banner Hill, Tennessee
- 2.3 6 km N of Greeneville, Tennessee
- 2.0 0 km SSE of Spruce Pine, North Carolina
- 2.5 11 km S of Tusculum, Tennessee
- 1.6 8 km SSE of Banner Hill, 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
- The official USGS event page — the source of record for every value above
- Did you feel it? Report it to USGS — reports go to USGS, not to us
- ShakeMap for this event, when USGS has produced one
QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.