Earthquake · reviewed by a seismologist
M 2.3md
Earthquake near Monarch Mill, SC
USGS: 3 km ENE of Monarch Mill, South Carolina
85 km (53 mi) SW of Charlotte, NC · 54 km (34 mi) WSW of Rock Hill, SC
- When
- 7:11 am EST on 17 February 2018 ()
- Where
- 3 km (2 mi) ENE of Monarch Mill, SC · earthquakes near Monarch Mill
- Magnitude
- M 2.3 (md)
- Depth
- 2.5 km below the surface
- Felt
- 4 reports · strongest reported intensity II
- Nearest
- Union County, 7 km WSW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2246 days ago
A magnitude 2.3 earthquake was recorded 3 km (2 mi) ENE of Monarch Mill, SC, at 7:11 am EST on 17 February 2018 (12:11 UTC). 4 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: Union, Buffalo, Whitmire, Pacolet.
How big was it?
This earthquake released about 88 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.
- Mineral, Virginia 2011 M 5.8 170,000× the energy of this one
- Magna, Utah 2020 M 5.7 120,000× the energy of this one
- Around the size people start to feel M 3.0 11× the energy of this one
- This earthquake M 2.3 about 88 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 34.7255, -81.5502. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Union County, SC | 7 km (4 mi) | WSW | earthquakes near Union County |
| Chester County, SC | 36 km (22 mi) | E | earthquakes near Chester County |
| Cherokee County, SC | 36 km (23 mi) | N | earthquakes near Cherokee County |
| York County, SC | 43 km (27 mi) | NE | earthquakes near York County |
| Spartanburg County, SC | 46 km (29 mi) | WNW | earthquakes near Spartanburg County |
| Newberry County, SC | 49 km (30 mi) | S | earthquakes near Newberry County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
20 earthquakes have been recorded within 50 km since this one.
- 2.1 9 km E of Cross Anchor, South Carolina
- 1.9 19 km NW of Winnsboro, South Carolina
- 1.9 9 km E of Cross Anchor, South Carolina
- 1.8 8 km E of Cross Anchor, South Carolina
- 2.4 18 km NW of Winnsboro, South Carolina
- 2.3 17 km NW of Winnsboro, South Carolina
- 1.7 19 km S of Gayle Mill, South Carolina
- 2.3 18 km NW of Winnsboro, South Carolina
- 2.4 8 km NNW of Jenkinsville, South Carolina
- 2.0 8 km N of Jenkinsville, South Carolina
- 1.9 7 km N of Jenkinsville, South Carolina
- 2.2 8 km NNW of Jenkinsville, South Carolina
- 1.8 8 km NNW of Jenkinsville, South Carolina
- 1.6 7 km ENE of Cross Anchor, South Carolina
- 2.3 8 km N of Jenkinsville, South 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
- 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.