Earthquake · reviewed by a seismologist
M 1.8ml
1 km ESE of Wellsville, Pennsylvania
- When
- Magnitude
- M 1.8 (ml)
- Depth
- 4.0 km below the surface
- Felt
- 19 reports · strongest reported intensity III
- Nearest
- York County, 21 km SE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 2352 days ago
This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 19 people have reported feeling it to USGS.
How big was it?
This earthquake released about 15 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.
- Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
- Magna, Utah 2020 M 5.7 710,000× the energy of this one
- Around the size people start to feel M 3.0 63× the energy of this one
- This earthquake M 1.8 about 15 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.
Where
Epicentre 40.0476, -76.9143. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction | |
|---|---|---|---|
| York County, PA | 21 km (13 mi) | NW of here | earthquakes near York County |
| Cumberland County, PA | 32 km (20 mi) | ESE of here | earthquakes near Cumberland County |
| Adams County, PA | 33 km (20 mi) | NE of here | earthquakes near Adams County |
| Dauphin County, PA | 42 km (26 mi) | SSW of here | earthquakes near Dauphin County |
| Perry County, PA | 49 km (31 mi) | SE of here | earthquakes near Perry County |
| Lebanon County, PA | 52 km (33 mi) | SW of here | earthquakes near Lebanon County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
No further earthquakes have been recorded within 50 km since this one.
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.