Seismic zone · Illinois, Missouri

Faults of Thebes Gap area

not measuredhow fast it slips

< 15,000 yearssince it last broke the surface

0quakes of M2.5+ within 10 km since 2016

In plain English

Its most recent surface rupture is younger than 15,000 years.

This week vs. its last ten years

Too quiet to rank: fewer than half a year's worth of weeks with any M1.5+ quake within 5 km, in ten years. A single quake here would read as "unusual", so we do not score it.

Computed 2026-09-28 23:45 UTC from the USGS catalogue · a description of the past, not a forecast · method

The Faults of Thebes Gap area as mapped at the surface (glowing), with the other mapped faults nearby, . Traces: USGS Quaternary Fault and Fold Database. Historic epicentres are estimates.

Neighbouring faults

Reelfoot scarp and New Madrid seismic zone 21 km away
St. Louis-Cape Girardeau liquefaction features 35 km away
Wabash Valley liquefaction features 39 km away

Fault trace, slip rate and age: USGS Quaternary Fault and Fold Database (public domain), simplified for the web. Earthquakes: USGS ComCat. QuakeIndex does not forecast earthquakes; a fault's history describes the past. For early warning use ShakeAlert.