Earthquake · reviewed by a seismologist
M 2.4ml
Earthquake near Portland, ME
No earthquake was likely felt in Portland in the 24 hours to 1:19 am EST (06:19 UTC). The last one was M 3.8, 70 km (44 mi) SSW, at 10:22 am EST on 27 January 2025, estimated intensity III (weak) in town; 42,440 felt reports to USGS. Every earthquake near Portland
This page: a magnitude 2.4 earthquake was recorded 48 km (30 mi) south-southeast of Portland, ME, at 2:54 am EST on 8 December 2021 (07:54 UTC), 10 km deep. 1 person has reported feeling it to USGS.
USGS: 42 km SE of Old Orchard Beach, Maine
43 km (26 mi) SSE of Portland, ME · 136 km (84 mi) NE of Boston, MA
- When
- 2:54 am EST on 8 December 2021 ()
- Where
- 48 km (30 mi) south-southeast of Portland, ME · earthquakes near Portland
- Magnitude
- M 2.4 (ml)
- Depth
- 10 km below the surface
- Felt
- 1 report · strongest reported intensity II
- Nearest
- York County, 59 km WNW
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 1733 days ago
Earthquake alerts for Portland, ME
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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 40 km (25 mi) from the epicentre. In Portland, 48 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.
How big was it?
This earthquake released about 120 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 5.8 130,000× the energy of this one
- Magna, Utah 2020 M 5.7 89,000× the energy of this one
- Around the size people start to feel M 3.0 7.9× the energy of this one
- This earthquake M 2.4 about 120 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 43.2861, -69.9643. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| York County, ME | 59 km (37 mi) | WNW | earthquakes near York County |
| Cumberland County, ME | 65 km (40 mi) | NNW | earthquakes near Cumberland County |
| Sagadahoc County, ME | 71 km (44 mi) | N | earthquakes near Sagadahoc County |
| Strafford County, NH | 87 km (54 mi) | W | earthquakes near Strafford County |
| Lincoln County, ME | 87 km (54 mi) | NNE | earthquakes near Lincoln County |
| Rockingham County, NH | 98 km (61 mi) | WSW | earthquakes near Rockingham County |
Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.
Aftershocks so far
1 earthquake has 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.