mining explosion · reviewed by a seismologist
M 2.6mb_lg
Earthquake near Williamsport, PA
No earthquake was likely felt in Williamsport in the 24 hours to 6:11 am EST (11:11 UTC). The last one was M 2.8, 45 km (28 mi) NE, at 4:04 pm EDT on 10 June 2025, estimated intensity II (weak) in town; 37 felt reports to USGS. Every earthquake near Williamsport
No: USGS classifies this as a mining explosion, not an earthquake. A magnitude 2.6 mining explosion was recorded 41 km (26 mi) northwest of Williamsport, PA, at 6:19 pm EDT on 5 April 2018 (22:19 UTC), less than 1 km deep. 19 people have reported feeling it to USGS.
USGS: 24 km WSW of Liberty, Pennsylvania
- When
- 6:19 pm EDT on 5 April 2018 ()
- Where
- 41 km (26 mi) northwest of Williamsport, PA · earthquakes near Williamsport
- Magnitude
- M 2.6 (mb_lg)
- Depth
- 0.0 km below the surface
- Felt
- 19 reports · strongest reported intensity IV
- Nearest
- Lycoming County, 31 km ESE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 3056 days ago
Earthquake alerts for Williamsport, PA
Get a notification in this browser when USGS records an earthquake near Williamsport, PA. 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 small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.
At this magnitude and depth, people at rest would likely notice it out to about 51 km (32 mi) from the epicentre. In Williamsport, 41 km away, the estimate is intensity II (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.
USGS catalogues this as mining explosion, not an earthquake.
How big was it?
This earthquake released about 240 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.6 would have released about 32 times as much.
- Mineral, Virginia 2011 M 5.8 63,000× the energy of this one
- Magna, Utah 2020 M 5.7 45,000× the energy of this one
- Around the size people start to feel M 3.0 4× the energy of this one
- This earthquake M 2.6 about 240 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 41.4780, -77.3828. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| Lycoming County, PA | 31 km (19 mi) | ESE | earthquakes near Lycoming County |
| Clinton County, PA | 34 km (21 mi) | SW | earthquakes near Clinton County |
| Tioga County, PA | 34 km (21 mi) | NNE | earthquakes near Tioga County |
| Potter County, PA | 52 km (32 mi) | NW | earthquakes near Potter County |
| Union County, PA | 64 km (39 mi) | SSE | earthquakes near Union County |
| Cameron County, PA | 68 km (42 mi) | W | earthquakes near Cameron County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
2 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.