Iola Anticline (New Name)

Old Name: Iola Dome

Location

T8N, R5E, Effingham County to T3N, R6E, Clay County (G, H-6)

References

J. Weller and Bell 1936

Description

J. Weller and Bell (1936) mapped a structure they called the Iola Dome in the northeast part of T4N, R4E, Marion County, and the northwest part of T4N, R5E, Clay County. Their map was based on scattered outcrops of upper Pennsylvanian limestone, and the existence of a dome in this area has not been borne out by subsequent study. The name Iola Anticline refers to an elongated southward-plunging anticline that contains the Iola Consolidated Oil Field and lies east of the Iola Dome.

The Iola Anticline can be discerned on maps of the New Albany Group (Stevenson et al. 1981) and Galena Group (Bristol and Buschbach 1973), but it is shown in greatest detail on maps of the Beech Creek ("Barlow") Limestone and Karnak Limestone Member of the Ste. Genevieve Limestone (ISGS open files). The anticline is approximately 32 miles (51 km) long and has an average width of about 2 miles (3 km) on these units. Several irregular areas of closure are present along the crest. Although total relief is less than 50 feet (15 m) in most places, the Iola Anticline is prominently shown on structure maps as it interrupts the gentle regional southeast dip. The northern terminus is indefinite. On the south, the anticline dies out just north of the Kenner Anticline.

The Iola Consolidated, Iola South, and Oskaloosa Oil Fields have been developed along the Iola Anticline. Cumulative production of these fields is about 24 million barrels from Chesterian, Valmeyeran, and Devonian reservoirs.