Nolichucky Formation (Campbell, 1894). Shale, siltstone, and limestone. Shale, locally calcareous, light-olive-gray and bluish-gray, fissile, with minor sandstone and dolomite. Siltstone, locally calcareous, yellowish-brown and grayish-orange, thin-bedded. Limestone, argillaceous to glauconitic, medium light-gray to dark-gray and bluish-gray, fine- to coarse-grained; contains oolitic- and flat-pebble conglomerate beds, locally stromatolitic. Shale and siltstone make up 20 to 50 percent of the formation (Derby, 1965). A limestone unit up to 165 feet in thickness is present approximately 100 feet above the base of the Nolichucky in northern Russell County (Miller and Meissner, 1977). The Nolichucky Shale ranges from 440 to 690 feet in thickness in Southwest Virginia but pinches out to the northeast in Giles County. Maryville Formation (Keith, 1895). Limestone, locally dolomitic, silty, medium- to dark-gray and bluish-gray, locally ribbon-banded, generally thick-bedded; with thin shale interbeds and sparse dolostone beds. May be as much as 60 percent oolitic limestone in some areas (Harris and Miller, 1958). The Maryville ranges from 500 to 700 feet in thickness. Rogersville Shale (Campbell, 1894). Shale, silty in part, dark-bluish-gray and dark-greenish-gray, fissile, with minor siltstone, limestone, dolostone, and sandstone. The Rogersville Shale ranges from 60 to 110 feet in thickness. Rutledge Formation (Campbell, 1894). Limestone and dolostone. Limestone, locally dolomitic, silty partings, medium-dark-gray to bluish-gray, thick-bedded, mottled, ribbon- banded, with minor chert. Dolostone, light-olive-gray and dark-gray, fine- to medium-grained, present in the upper part of the formation in eastern Scott County. The formation forms prominent bluffs on the south-side of Clinch River and Copper Creek in Scott and Russell counties. The Rutledge ranges from 215 to 375 feet in thickness. The Maryville Formation, Rogersville Shale, and Rutledge Formation grade from predominantly limestone with subordinate dolostone and shale in southeastern Lee County and southwestern Scott County to limestone with a middle dolostone and thin shale near the Scott County-Russell County line. Northeast of this area the laterally equivalent rocks are predominantly dolostone with subordinate lime stone at the top and bottom and are called the Honaker Formation (Evans and Troensegaard, 1991).