Blackoak Dome (Discarded)

Location

Southwestern T3N, R14W, Richland County

References

Easton 1943

Description

When Easton (1943) defined the Blackoak Dome, he was using subsurface mapping of two Mississippian units, the Beech Creek ("Barlow") Limestone and Levias Member of the Renault Limestone. The map shows a roughly oval dome that is about 3 miles (5 km) long from north to south, and has about 30 feet (9 m) of closure. The current Beech Creek structure map (ISGS open files), based on dozens of control points not available to Easton, shows no dome or anticline in the vicinity of Easton's Blackoak Dome. Instead, the area is depicted as an irregular terrace on the east flank of a syncline, east of the Clay City Anticline. The Parkersburg Dome, which Easton placed south of the Blackoak Dome, proves to be part of the same terrace. Because of the lack of demonstrated closure, the names Blackoak and Parkersburg Domes should be discontinued.