Pg. 276, 384, 385. Fentress shale division in Lee formation. Name proposed for the part of Lee formation, in Fentress and Pickett Counties, northern Tennessee, beneath Rockcastle sandstone. Consists mainly of shales (fine clay shales and sandy shales), but may contain some beds of sandstone and usually has two coal horizons, on just above its base and the other not over a score or two of feet below its top. The shales change locally along the bedding into shaly sandstone. Thickness of the division may be as much as 175 feet. Laid down on irregular erosional surface of Pennington formation (Mississippian). Upper part has been cut away locally at least. Age is Pennsylvanian.
[Type locality not stated, but presumably the beds were named from their development in Fentress Co., northern TN.]

Source: US geologic names lexicon (USGS Bull. 896, p. 726).

Pg. 1, 4. Fentress formation. Glenn used name Fentress shale to include all strata of Pennsylvanian age beneath Rockcastle conglomerate in Fentress County and vicinity, [northern Tennessee], where these beds are primarily shale and where Sewanee conglomerate is too thin to be mapped. Name is here changed to formation because of local occurrences of sandstone. Definition, however, remains the same. Formation includes beds equivalent to parts of two groups: the entire Gizzard group and all of Crab Orchard Mountains group (new) below Rockcastle conglomerate; hence, it is equivalent to Raccoon Mountain formation (new). Warren Point sandstone, Signal Point shale (new), Sewanee conglomerate, Whitwell shale, Newton sandstone, and Vandever formation. In localized areas, some of the constituent formations are recognizable. Name, Fentress formation, is used only where Sewanee conglomerate is not mappable. Age is Early Pennsylvanian (Pottsville).

Source: US geologic names lexicon (USGS Bull. 1200, p. 1336).

(East-central sheet.) Fentress Formation. Mostly dark-gray to light-brown shale with minor siltstone and sandstone. Wilder coal near middle. Laterally equivalent to entire Gizzard Group and all of Crab Orchard Mountains Group below Rockcastle Conglomerate. Thickness as much as 340 feet. Age is Pennsylvanian.

Source: Publication.

Fentress Formation of Pennsylvanian age used in Chattanooga 2-degree quad.

Source: GNU records (USGS DDS-6; Reston GNULEX).

Name used as either Fentress Formation or Fentress Shale in TN. Name was proposed for strata previously of Lee Formation below Rockcastle Sandstone in Fentress and Overton Cos., where Warren Point Sandstone, Sewanee Conglomerate, and Newton Sandstone are thin or absent and all of lower part of Lee is predominantly shale. Correlates with Gizzard Group through Vandever Formation of southern TN.

Source: GNU records (USGS DDS-6; Reston GNULEX).