Geologic units in Dade county, Georgia

Additional scientific data in this geographic area

Lookout Sandstone; Sewanee Sandstone (Pennsylvanian) at surface, covers 22 % of this area

Lookout Sandstone; Sewanee Sandstone

Mississippian undifferentiated (Mississippian) at surface, covers 18 % of this area

Includes Pennington Shale, Bangor Limestone (except in Floyd County), Hartselle Sandstone, Golconda Formation, Gasper Limestone, Ste. Genevieve Limestone and St. Louis Limestone

Pennsylvanian undifferentiated (Pennsylvanian) at surface, covers 15 % of this area

Pennsylvanian undifferentiated

Lookout Sandstone; Gizzard Formation (Pennsylvanian) at surface, covers 14 % of this area

Lookout Sandstone; Gizzard Formation

Chickamauga Group undivided (Ordovician) at surface, covers 11 % of this area

Chickamauga Group undivided

Devonian-Missisippian undivided (Devonian-Mississippian) at surface, covers 9 % of this area

Includes Fort Payne Chert, Chattanooga Shale in Dade Co.; Fort Payne Chert at top, Chattanooga Shale in middle and Armuchee Shale at bottom in all areas except Polk Co. and Dade Co.; Fort Payne Chert, and Armuchee Chert in Polk Co. CHATTANOOGA Shale (Dc)

Red Mountain Formation (Silurian) at surface, covers 9 % of this area

Red Mountain Formation

Knox Group undifferentiated (Ordovician-Cambrian) at surface, covers 1 % of this area

Knox Group undifferentiated

Gizzard Group, including Signal Point Shale, Warren Point Sandstone, and Raccoon Mountain Formation (Pennsylvanian) at surface, covers 0.2 % of this area

Gizzard Group - Shale, siltstone, sandstone, and conglomerate; from base of Sewannee Conglomerate to top of Mississippian. Thickness 0 to 520 feet, including Signal Point Shale - Mostly dark-gray to light-brown shale, with minor siltstone. Wilder coal near top. Thickness 0 to 180 feet, average about 60 feet; Warren Point Sandstone - Sandstone and conglomeratic sandstone, gray to brown, fine- to medium-grained, locally interbedded with shale containing coal. Thickness 0 to 300 feet, thins from southeast to northwest, average thickness about 100 feet; Raccoon Mountain Formation - Shale, siltstone, and sandstone. Bon Air coal near top; White Oak and Sale Creek coals near base. Thickness 0 to 260 feet.

Pennington Formation (Mississippian) at surface, covers 0.1 % of this area

Highly variegated clay shale, distinctive; contains siltstone and locally gray, fine-grained sandstone. Thickness 400 to 700 feet.

Newman Limestone (Mississippian) at surface, covers 0.1 % of this area

Gray limestone sequence near Cumberland Plateau and on Whiteoak Mountain. Shaly limestone, shale, siltstone, and sandstone on Chilhowee Mountain. Thickness about 700 feet.

Rockwood Formation (Silurian) at surface, covers < 0.1 % of this area

Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 200 to 800 feet.

Monteagle Limestone (Mississippian) at surface, covers < 0.1 % of this area

Mainly fragmental and oolitic, light-gray limestone; blocky bryozoan chert weathers from base. Thickness 180 to 300 feet.

Red Mountain Formation (Silurian) at surface, covers < 0.1 % of this area

Interbedded yellowish-gray to moderate-red sandstone, siltstone and shale; greenish-gray to moderate-red fossiliferous partly silty and sandy limestone; few thin hematitic beds.

Fort Payne Formation (Mississippian) at surface, covers < 0.1 % of this area

Bedded chert, calcareous and dolomitic, somewhat crinoidal; and minor shale. Thin green shale (Maury) at base. Average thickness about 200 feet.

Tuscumbia Limestone and Fort Payne Chert undivided (Mississippian) at surface, covers < 0.1 % of this area

Tuscumbia Limestone -- light-gray partly oolitic limestone; very coarse bioclastic crinoidal limestone common; light-gray chert nodules and concretions locally abundant. Fort Payne Chert -- very light to light-olive-gray, thin to thick-bedded fine to coarse-grained bioclastic (abundant pelmatozoans) limestone containing abundant nodules, lenses and beds of light to dark-grey chert. Upper part of formation locally consists of light-bluish-gray laminated siltstone containing vugs lined or filled with quartz and scattered throughout the formation are interbeds of medium to greenish-gray shale, shaly limestone and siltstone. Lenses of dark-gray siliceous shale occur locally at the base of the Fort Payne in Wills Valley. Commonly present below the Fort Payne is a ligh-olive-gray claystone or shale (Maury Formation) which is mapped with the Fort Payne. The Tuscumbia and Fort Payne are undifferentiated in Murphrees and Wills Valleys.

Sequatchie Formation (Ordovician) at surface, covers < 0.1 % of this area

Maroon and gray shaly limestone, mottled greenish; with interbeds of calcareous, olive to maroon shale and siltstone. Average thickness about 200 feet.

Pottsville Formation (Pennsylvanian) at surface, covers < 0.1 % of this area

Light-gray thin to thick-bedded quartzose sandstone and conglomerate containing interbedded dark-gray shale, siltstone, and coal. Mapped on Lookout Mountain, Blount and Chandler Mountains, and Sand Mountain northeats of Blount County, and on the mountains of Jackson, Marshall and Madison Counties north and west of the TN river.

Chickamauga Group, includes Upper part of Chickamauga Group (Reedsville Shale, and Unnamed limestone unit) and Middle and Lower part of Chickamauga Group (Moccasin Formation, Bays Formation, Ottosee Shale, Holston Formation, Lenoir Limestone, Athens Shale, and Sevier Shale) (Ordovician) at surface, covers < 0.1 % of this area

In the northwest part of the Valley and Ridge a predominantly limestone sequence about 2,000 feet thick. Becomes progressively more clastic and thicker to the southeast, including Upper part of Chickamauga Group (Reedsville Shale- Greenish-gray calcareous shale. Thickness 0 to 400 feet, and Unnamed Limestone Unit - Medium-grained, fossiliferous, gray limestone, shaly in part. Thickness as much as 600 feet ) and.Middle and lower parts of Chickamauga Group (Omlc).

Bangor Limestone and Hartselle Formation (Mississippian) at surface, covers < 0.1 % of this area

Bangor Limestone - Dark brownish-gray limestone, thick-bedded. Thickness 70 to 400 feet., and Hartselle Formation - Thin-bedded, fine-grained sandstone interbedded with gray shale; with oolitic and coarse-grained limestone beds locally. Thickness 0 to 80 feet.

Monteagle Limestone (Mississippian) at surface, covers < 0.1 % of this area

Light-gray oolitic limestone containing interbedded argillaceous, bioclastic, or dolomitic limestone, dolomite, and medium-gray shale.

Parkwood and Pennington Formations undifferentiated (Pennsylvanian-Mississippian) at surface, covers < 0.1 % of this area

Interbedded medium to dark-gray shale and light to medium-gray sandstone, locally contains lithic conglomerate, dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal.

Bangor Limestone (Mississippian) at surface, covers < 0.1 % of this area

Medium-gray bioclastic and oolitic limestone, containing interbeds of dusky-red and olive-green mudstone in upper part.

Crab Orchard Mountains Group, including Rockcastle Conglomerate, Vandever Formation, Newton Sandstone, Whitwell Shale, and Sewanee Conglomerate (Pennsylvanian) at surface, covers < 0.1 % of this area

Crab Orchard Mountains Group - Conglomerate, sandstone, siltstone, shale, and coal; from top of Rockcastle Conglomerate to base of Sewanee Conglomerate. Thickness 200 to 950 feet; including Rockcastle Conglomerate - Conglomeratic sandstone and sandstone, gray to brown, fine- to coarse-grained. Thin coal-bearing shale locally present near middle. Thickness 150 to 220 feet; Vandever Formation - Mostly shale and siltstone, dark-gray to light-brown; conglomerate or sandstone in middle to south. Lantana and Morgan Springs coals near base and top. Thickness as much as 450 feet, average about 300 feet; Newton Sandstone - Sandstone, gray to brown or pink, fine- to medium-grained, locally conglomeratic. Thickness as much as 200 feet; average about 90 feet; Whitwell Shale - Mostly dark-gray to light-brown shale, with minor siltstone; locally middle part is sandstone. Richland coal near base; Sewanee coal in upper part. Thickness as much as 220 feet, average about 75 feet; Sewanee Conglomerate - Conglomeratic sandstone and sandstone, gray to brown, fine- to coarse-grained. Thickness as much as 200 feet, average about 100 feet.

St. Louis Limestone and Warsaw Limestone (Mississippian) at surface, covers < 0.1 % of this area

St. Louis Limestone - Fine-grained, brownish-gray limestone, dolomitic and cherty. Thickness 80 to 160 feet.; and Warsaw Limestone - Mainly medium- to coarse-grained, gray limestone, crossbedded. Includes much calcareous sandstone and shale to the north. Thickness 100 to 130 feet.