Brushy Anticline
Part of the Cottage Grove Fault System
Location
T9N, R5E, Saline County (J-6)
References
Cady et al. 1939, Nelson and Krausse 1981
Description
Cady et al. (1939) originally defined the anticline on the basis of drill-hole data on the Herrin Coal Member (Pennsylvanian). Subsequent elevation surveys and geologic studies in underground coal mines now provide detailed information on the Brushy Anticline at the level of the Springfield Coal Member (fig. 21).
The Brushy Anticline lies between two westward-converging branches of the master fault of the Cottage Grove Fault System. The anticline has a broad, almost flat crest and steep limbs near the bordering faults (fig. 21). Maximum structural relief on the Springfield Coal is about 140 feet (43 m). Several northwest-trending, high-angle normal and oblique-slip faults have been encountered in coal mines in the central area of the anticline.
Located as it is, within an upthrust block between segments of a wrench fault system, the Brushy Anticline fits the definition of a positive flower structure (Harding 1985).
