Pontiac Dome

Location

T27 and 28N, R6E, Livingston County (D-6)

References

Buschbach and Bond 1974, Jacobson 1985

Description

Pontiac Dome is best described as two domes separated by a saddle. The southern dome is nearly circular and approximately 2 miles (3 km) in diameter. It has about 100 feet (30 m) of closure on the top of the basal Cambrian Mt. Simon Sandstone that was developed as a gas storage reservoir. The northern dome is smaller than the southern and more irregular in outline. Its closure is about 70 feet (21 m) on the Mt. Simon Sandstone. Both domes lie along the axis of a broad, south-plunging anticline.

The configuration of Pontiac Dome, as contoured on the Pennsylvanian Colchester Coal Member (Jacobson 1985), is similar to that contoured on the Mt. Simon, but the amount of closure is less on the younger horizon. The Pontiac Dome lies within the broad confines of the La Salle Anticlinorium, but whether a genetic relationship exists is not known.