Olmsted fault: Connecting New Madrid to Wabash Valley

To the immediate east northeast of Pulaski quadrangle is the Cypress quadrangle. Of interest is the Cache River valley and Olmsted fault. A new large lock and dam is under construction on the Ohio River near Olmstead. See cross section at bottom of this pdf. http://www.isgs.uiuc.edu/maps-data-pub/statemap/pdf-files/cypress-g.pdf

This map shows the Olmsted fault going literally through Olmsted and within a mile or so of the new and old locks and dams Click the map for the source. New Madrid and Wabash Valley faults are connected through here and Rough Creek Graben.

The "feather trail" went from this spot - New Caledonia - to Jonesboro IL, and was one of the earliest European trails in Southern Illinois. It was said to be littered with feathers of caged chickens on their way to market.

Earthquakes in Southern Illinois
The quake lines in right side of map are a connection between the Wabash and New Madrid Faults.

Cross section below - click for double size -is cross-section of land between Ullin and Grand Chain, showing Perks Road, Shawnee College with Olmsted fault underneath, and Illinois Route 37. The yellow-salmon colored channel probably carried the Ohio River at one time, perhaps when the ocean levels were lower than now.

http://www.isgs.uiuc.edu/maps-data-pub/statemap/pdf-files/cypress-g.pdf

Quake sitemap