QuakeIndex

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

3:30 am CDT, Sep 19, 2024 · · 2.1 km deep · released about 220 lb of TNT

10 km30 km60 km120 km N St. Charles County 16 kmLincoln County 25 kmCalhoun County 28 kmJersey County 38 kmWarren County 40 kmSt. Louis County 40 kmSt. Louis city 54 kmGreene County 58 kmPike County 60 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
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

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.

  1. Mineral, Virginia 2011 M 5.8 70,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 50,000× the energy of this one
  3. Around the size people start to feel M 3.0 4.4× the energy of this one
  4. 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

PlaceDistanceDirection 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

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.