Woburn Anticline (New)

Location

Northeastern Bond County (G, H-5)

References

Bristol and Buschbach 1973, Bristol and Howard 1976, Stevenson et al. 1981

Description

The Woburn structure, formerly referred to as a "significant unnamed structure" (Treworgy 1981), is now named the Woburn Anticline. The name comes from a nearby town and the Woburn Consolidated Oil Field that is developed in a structural trap on the anticline. Structure maps of the Beech Creek ("Barlow") Limestone (ISGS open files) show a prominent linear anticline, plunging slightly west of south and having several areas of closure. The anticline is about 10 miles (16 km) long and 3 to 4 miles (5-6.5 km) wide. Maximum closure is only about 20 feet (6 m) on the Beech Creek but total structural relief is greater than 150 feet (45 m). On the older Karnak Limestone Member, the Woburn Anticline is shown to have closure of more than 100 feet (30 m) (R. Howard, unpublished mapping). The west limb is nearly linear and dips more steeply than the east limb at this horizon. The form of the west limb suggests an underlying basement fault.

The Woburn Anticline also is mapped as having closure on the Ste. Genevieve Limestone (Bristol and Howard 1976), the base of the New Albany Group (Stevenson et al. 1981), and the Galena (Trenton) Group (Bristol and Buschbach 1973). Woburn is one of several small north-trending anticlines on the eastern Sparta Shelf.