QuakeIndex

Earthquake · reviewed by a seismologist

M 2.3md

4 km S of Valmeyer, Illinois

· 5.6 km deep · released about 94 lb of TNT

10 km30 km60 km120 km N Monroe County 9 kmJefferson County 23 kmSt. Clair County 39 kmSt. Louis city 42 kmSte. Genevieve County 43 kmSt. Louis County 44 kmRandolph County 46 kmSt. Francois County 53 kmWashington County 64 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 2.3 (md)
Depth
5.6 km below the surface
Felt
43 reports · strongest reported intensity IV
Nearest
Monroe County, 9 km ENE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 529 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage. 43 people have reported feeling it to USGS.

How big was it?

This earthquake released about 94 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.3 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 160,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 110,000× the energy of this one
  3. Around the size people start to feel M 3.0 10× the energy of this one
  4. This earthquake M 2.3 about 94 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 38.2617, -90.2825. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Monroe County, IL 9 km (6 mi) WSW of here earthquakes near Monroe County
Jefferson County, MO 23 km (14 mi) E of here earthquakes near Jefferson County
St. Clair County, IL 39 km (24 mi) SW of here earthquakes near St. Clair County
St. Louis city, MO 42 km (26 mi) S of here earthquakes near St. Louis city
Ste. Genevieve County, MO 43 km (27 mi) NNW of here earthquakes near Ste. Genevieve County
St. Louis County, MO 44 km (28 mi) SSE of here earthquakes near St. Louis County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

3 earthquakes have been recorded within 50 km since this one.

  1. 2.0 6 km SSW of Valmeyer, Illinois
  2. 2.4 3 km ESE of Fenton, Missouri
  3. 1.7 3 km WNW of Olympian Village, Missouri

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.