Breathitt Formation is informally elevated to group rank and subdivided into the following eight informal formations: Pocahontas, Bottom Creek, Alvy Creek, Grundy, Pikeville, Hyden, Four Corners, and Princess formations. Grundy formation includes informal shale member B, Naese coal bed shale member C, Clear Fork coal bed, Dave Branch shale member (here informally named), Grayhawk coal bed shale member D, Hagy coal, Molus shale member (informally named), Mason coal, Partridge shale member (informally named), Eagle coal bed, Vancleve(?) coal bed, and Manchester coal bed. Shale member B at the base of the Grundy overlies the Bee Rock Sandstone Member of the Lee Formation. [Revisions made in this paper are strongly contested by C. Rice and other USGS scientists who work in this area (oral commun., 9/3/93).]

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

Grundy Formation of Breathitt Group is an important coal-bearing unit, formally named in this report for Grundy, VA. A reference section is designated in southern Pike Co., KY. Reaches a maximum thickness of 260 m. Overlies Bee Rock Sandstone of Breathitt Group in KY and TN or Alvy Creek formation of Breathitt in southwestern WV and VA, where the Kennedy coal bed forms its base. Interbeds with the Bee Rock toward the southeast. Underlies the Betsie Shale Member of the Pikeville Formation. Most extensive of all the formations within the Breathitt Group, which is here formally raised in rank and subdivided into ten formal formations and two informal formations. The Grundy contains [surrounds] the Corbin Sandstone along the western part of the study area, and the Gladeville Sandstone in its upper part in southeastern KY, southern WV, and VA. Dave Branch shale member is shown at the base of the Grundy in fig. 5, but is not mentioned in the text. Member appears to be present in northern TN and eastern KY. Major coals within the Grundy and other Breathitt formations are shown on Plate 8, but according to author are not necessarily the correct correlations used throughout TN, KY, VA, and WV. Studies are in progress to resolve correlation problems. Author states formal nomenclature presented in this report for units occurring in KY has been accepted by the Kentucky Stratigraphic Nomenclature Committee. Units that occur largely outside KY are considered informal. Report includes correlation charts, cross sections, and measured sections.

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

Grundy Formation of Breathitt Group of Chesnut (1992); Grundy unit (informal) in Breathitt Formation of Rice and others (1994, GSA Spec. Paper, p. 128, citing Chesnut, 1989). Not used. [Rocks assigned to the Grundy Formation by Chesnut (1992) are in lower part of Breathitt Formation, from base of Betsie Shale Member (= top of Copland, Limestone, Sharp, or Taylor coals) down to base of Magoffin Member (= top of Bennetts Fork, Bingham, Colony, Hance, Horse Creek, Lily, Manchester, Puckett Creek, River Gem, Swamp Angel, or Zachariah coals).]

Source: Publication.

Corr. chart. Grundy Formation of Breathitt Group. Sandstone, siltstone, shale, and coal. Recognized in eastern and southeastern Kentucky. Lies below Betsie Shale Member of Pikeville Formation of Breathitt Group. [Eble and others (2009, Kentucky Geol. Survey, ser. XII, Spec. Pub. 10, figs. 5.1, 5.2) placed the Betsie Shale Member at the Langsettian/Duckmantian (Westphalian A/B) boundary on basis of miospores.] In eastern Kentucky lies above Pine Creek sandstone member (informal) of Bee Rock Sandstone, and in southeastern Kentucky [Upper Cumberland River district] lies above Naese Sandstone Member of Bee Rock Sandstone; all of Breathitt Group. Age is Early Pennsylvanian (Westphalian; Morrowan). [Eble and others (2009, Kentucky Geol. Survey, ser. XII, Spec. Pub. 10, fig. 5.2) placed beds approx = base of Grundy (Douglas coal bed of West Virginia) in upper part of Langsettian (upper part of Westphalian A) on basis of miospores.]
In eastern Kentucky, includes (descending) Manchester (Zachariah, Clintwood, Williamson) coal bed, unranked Corbin Sandstone, informal Partridge shale member, Millard (Glamorgan) coal bed, informal Molus shale member, Hagy rider coal, Hagy coal zone, Splash Dam (Gray Hawk, Mine Fork) coal bed, unranked Hazel Patch sandstone, informal Dave Branch shale member, Upper Banner coal bed, and Lower Banner coal bed.
In southeastern Kentucky, includes (descending) Hance coal zone, informal Partridge shale member, Mason rider coal, Mason (Chenoa) coal bed, informal Molus shale member, Splitseam coal bed, informal Dave Branch shale member, Clear Fork (Rex) coal bed, and Yellow Creek Sandstone Member.
[See also Chesnut, 1997 (revised Oct. 12, 1999), Stratigraphy of the coal-bearing strata of the Eastern Kentucky coal field, available online through the Kentucky Geol. Survey (http://www.uky.edu/KGS/coal/coalcorrel.htm) and geologic descriptions of stratigraphic units in the Kentucky Geological Survey database (http://kgs.uky.edu/kgsmap/KGSLitho/lithoSearch.asp#).]

Source: Publication.