Fancher-Mode Anticline (Discarded)

Location

T10S, R4E, Shelby County

References

Newton 1941

Description

Newton (1941) defined the Fancher-Mode Anticline as a northeast-plunging anticline that is about 5 miles (8 km) long and has three areas of closure. He mapped it primarily on the basis of outcrop study and selected the "upper Bogota limestone" of the Virgilian Series (upper Pennsylvanian) as his contouring horizon. More recent studies have demonstrated that Newton and other early researchers miscorrelated upper Pennsylvanian strata (Weibel 1986). The contouring that Newton used to define the anticline is questionable.

Subsequent development of the Clarksburg (discovered 1946), Mode (1961), and Fancher (1962) Oil Fields has provided borehole data that demonstrate that structural highs exist in T10S, R4E, Shelby County. The structural pattern mapped on the Beech Creek ("Barlow") Limestone (ISGS open files) bears little resemblance, however, to the anticline mapped by Newton. Each of the three fields occupies a separate circular or ovoid dome having 10 to 15 feet (3-4.5 m) of closure on the Beech Creek. The Fancher Oil Field is located near the southwest end of Newton's Fancher-Mode Anticline, but the Mode and Clarksburg fields are considerably northwest of Newton's structure. Regional dip is east-southeast.

The name Fancher-Mode Anticline should be discontinued because no anticline is present. The three small domes are not worth naming.