Pg. 485-499. Cumberland Gap shale member of Chattanooga shale. Lower black shale member of Chattanooga shale [restricted]. Conformably underlies Olinger gray shale member, the middle member of Chattanooga shale. [On p. 499: The Olinger member is of the same age as the [upper part of the] Cumberland Gap member, with which it intertongues to south, representing merely a different environmental condition. In southeastern Tennessee rests unconformably on Rockwood formation. From Rockwood northward it everywhere rests on interbedded gray and black shale of Portage age. Clearly exposed along Lee Highway on north edge of town of Cumberland Gap, Tennessee. In vicinity of Chattanooga, Tennessee, it is about 8 feet thick; at Hagans, Virginia, 127 feet 7 inchess thick; at Big Stone Gap, Virginia, about 90 feet. [Age is Devonian or Carboniferous.]
See also Wilmarth, M.G., compiler, 1929, Tentative correlation of the named geologic units of Tennessee, USGS unpub. corr. chart, Aug., 1929, sheet 2 of 4, and Tentative correlation of the named geologic units of Virginia, USGS unpub. Corr. Chart, Apr., 1929, sheet 2 of 2.

Source: US geologic names lexicon (USGS Bull. 896, p. 554).

Pg. 431-448. Cumberland Gap shale member of Chattanooga shale. Assigned these beds to Mississippian.

Source: US geologic names lexicon (USGS Bull. 896, p. 554).