Earthquake · reviewed by a seismologist
M 2.6md
Earthquake near O'Fallon, MO
No earthquake was likely felt in O'Fallon in the 24 hours to 4:31 am CST (10:31 UTC). The last one was M 3.5, 239 km (149 mi) E, at 2:05 am CDT on 29 June 2026, estimated intensity II (weak) in town; 392 felt reports to USGS. Every earthquake near O'Fallon
This page: a magnitude 2.6 earthquake was recorded 13 km (8 mi) north-northwest of O'Fallon, MO, at 3:30 am CDT on 19 September 2024 (08:30 UTC), 2.1 km deep. 86 people have reported feeling it to USGS.
USGS: 1 km S of Old Monroe, Missouri
15 km (9 mi) N of O'Fallon, MO · 54 km (33 mi) NW of St. Louis, MO
- When
- 3:30 am CDT on 19 September 2024 ()
- Where
- 13 km (8 mi) north-northwest of O'Fallon, MO · earthquakes near O'Fallon
- Missouri today
- every earthquake in Missouri in the last 24 hours
- Magnitude
- M 2.6 (md)
- Depth
- 2.1 km below the surface
- Felt
- 86 reports · strongest reported intensity V
- Nearest
- St. Charles County, 16 km SSE
- Status
- Reviewed by a seismologist
USGS · last changed by USGS · we first saw it 717 days ago
Earthquake alerts for O'Fallon, MO
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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 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 49 km (30 mi) from the epicentre. In O'Fallon, 13 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: Saint Paul, Winfield, Lake Saint Louis, Wentzville, Moscow Mills, Dardenne Prairie.
How big was it?
This earthquake released about 220 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 70,000× the energy of this one
- Magna, Utah 2020 M 5.7 50,000× the energy of this one
- Around the size people start to feel M 3.0 4.4× the energy of this one
- This earthquake M 2.6 about 220 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 38.9180, -90.7468. Map © OpenStreetMap contributors.
Nearby places
| Place | Distance | Direction from the epicentre | |
|---|---|---|---|
| St. Charles County, MO | 16 km (10 mi) | SSE | earthquakes near St. Charles County |
| Lincoln County, MO | 25 km (15 mi) | NW | earthquakes near Lincoln County |
| Calhoun County, IL | 28 km (18 mi) | NNE | earthquakes near Calhoun County |
| Jersey County, IL | 38 km (24 mi) | ENE | earthquakes near Jersey County |
| Warren County, MO | 40 km (25 mi) | WSW | earthquakes near Warren County |
| St. Louis County, MO | 40 km (25 mi) | SE | earthquakes near St. Louis 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.