Pecatonica Anticline (New Name)

Old Name: Pecatonica Dome

Location

T26 and 27N, R10E, Winnebago County (A-5)

References

Buschbach and Bond 1974

Description

The Pecatonica Anticline is a northwest-trending structure at least 6 miles (10 km) long and as much as 2 miles (3 km) wide. The northeast flank is the steeper. The anticline has about 30 feet (9 m) of closure, covering 4 square miles (10 km²). A gas storage field has been developed on it with the Proviso Siltstone Member of the Eau Claire Formation (Cambrian) serving as the reservoir. Treworgy (1981) labeled this structure a dome, but it should be called an anticline because its length is more than twice its width.