This State of Tennessee Geologic Quad Mosaic consists of 24 joined sheets. Use the controls on the bottom right hand side of the window above to pan/zoom - or better yet to go full screen (or use your mouse).
The formation designations may vary between the different years of mapping efforts, but generally follows that enumerated below.
| Map Label | Unit Name | Unit Age | Unit Description |
| Cc | Conasauga Group, including Maynardville Limestone, Nolichucky Shale, the Maryville, Rogersville, and Rutledge Formations, Pumpkin Valley Shale, Rome Formation, and Shady Dolomite | Cambrian | Conasauga Group - Mostly shale northwest of a line connecting Etowah and Bearden (Knoxville); to the east it consists of the six formations at right [Cmn, Maynardville Limestone. Ccl including Cn, Nolichucky Shale, Cmr Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale; Cr, Rome Formation, and Cs, Shady Dolomite. Thickness about 2,000 feet. |
| Cc | Conasauga Group | Cambrian | Conasauga Group - Mostly shale northwest of a line connecting Knoxville and Tazewell; dominantly dolomite with minor shale southeast of a line from Newport to Kingsport; between these lines it consists of six formations. Thickness about 2,000 feet. |
| Cc | Conasauga Group, includes Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale, Rome Formation, Shady Dolomite | Cambrian | Conasauga Group, includes Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale, Rome Formation, Shady Dolomite |
| Ccc | Conococheague Limestone | Ordovician | Conococheague Limestone - Well-bedded, ribboned (silt and dolomite), dark-gray limestone; interbeds of fine-grained, light- to dark-gray dolomite; sparingly cherty; cryptozoans typical. Thickness about 1,500 feet. |
| Cch | Chilhowee Group; Cochran Conglomerate | Cambrian | Chilhowee Gourp; Cochran Conglomerate - Quartz-pebble conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding, scour features, crossbedding common; maroon micaceous arkose and shale near middle and base. Thickness about 1,200 feet. |
| Cch | Cochran Conglomerate | Cambrian | Cochran Conglomerate - Quartz-pebble conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding, scour features, crossbedding common; maroon micaceous arkose and shale near middle and base. Thickness about 1,200 feet. |
| Cchi | Chilhowee Group, including Erwin Formation, Hesse Sandstone, Murray Shale, Nebo Sandstone, Nichols Shale, Cochran Conglomerate, Hampton Formation, and Unicoi Formation | Cambrian | Chilhowee
Group - Conformable sequence of dominantly clastic sediments. Thickness 3,000
to 7,500 feet; including Erwin Formation - White, vitreous quartzite,
massive, with interbeds of dark-green silty and sandy shale, minor siltstone,
and very fine-grained sandstone. Thickness 1,000 to 1,500 feet; Hesse
Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in
massive ledges; Helenmode Member at top is gray to greenish sandstone and
shale. Thickness about 600 feet; Murray Shale - Shale, silty, sandy,
dull-green to brown, micaceous. Thickness about 500 feet; Nebo Sandstone -
Medium-bedded, fine-grained, white, vitreous quartzite, in part feldspathic.
Thickness 250 feet; Nichols Shale - Olive-gray to green, silty and sandy,
micaceous shale and siltstone; local lenses of fine-grained feldspathic
quartzite. Thickness about 700 feet; Cochran Conglomerate - Quartz-pebble
conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding,
scour features, crossbedding common; maroon micaceous arkose and shale near
middle and base. Thickness about 1,200 feet; Hampton Formation - Dark
greenish-gray, silty and sandy, micaceous shale; numerous layers of
medium-grained, feldspathic, thinly bedded sandstone. Thickness 500 to 2,000
feet; Unicoi Formation - Sequence of gray feldspathic sandstone, arkose,
conglomerate, graywacke, siltstone and shale; greenish amygdaloidal basalt
flows near middle and base. Thickness 2,000 to 5,000 feet. |
| Ccl | Nolichucky Shale, and Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale | Cambrian | (Cn)
Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale;
gray, commonly oolitic, shaly limestone lenses; locally stromatolitic
limestone layers; thin, blocky siltstone near middle. Thickness 500 feet in
the east to 900 feet in the west.; (Cmr) Maryville, Rogersville, and Rutledge
Formations - Maryvile and Rutledge are gray limestone, in part oolitic, with
gray dolomite locally. Rogersville is green clay shale. Thickness 400 to
1,000 feet. Pumpkin Valley Shale - Dull-brown to maroon shale with numerous
interbeds of thin, blocky, sandy siltstone. Thickness 100 to 600 feet. |
| Ccl | Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale | Cambrian | Maynardville
Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite) nodular
limestone; light-gray, fine-grained, laminated to thinly bedded, noncherty
dolomite in upper part. Thickness 150 to 400 feet; Nolichucky Shale -
Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly
oolitic, shaly limestone lenses; locally stromatolitic limestone layers;
thin, blocky siltstone near middle. Thickness 100 feet in the east to 900
feet in the west; Honaker Dolomite - Dark-gray, medium-bedded dolomite with
minor dark limestone beds; locally cherty; cryptozoans abundant in places.
Thickness about 1,500 feet; Maryville Limestone - Gray, ribboned (silt and
dolomite), fine-grained, evenly bedded limestone; intraformational
conglomerate and oolitic layers common; clay shale and light-gray dolomite
locally. Thickness 300 to 800 feet; Rogersville Shale - Light-green, fissile
clay shale; in places limestone (Craig Member) in upper part. Commonly 25 to
80 feet thick; maximum thickness 250 feet; Rutledge Limestone - Medium- to
dark-gray, ribboned (silt and dolomite), medium-grained, well-bedded
limestone; locally dark-gray, coarse-grained, medium-bedded dolomite in upper
part. Thickness 100 to 500 feet; Pumpkin Valley Shale - Dull-brown to maroon
shale with numerous interbeds of thin, blocky, and sandy siltstone. Thickness
100 to 600 feet. |
| Ccr | Copper Ridge Dolomite | Cambrian | Copper Ridge Dolomite - Coarse, dark-gray, knotty dolomite, asphaltic in places, with much gray, medium-grained, well- bedded dolomite; abundant chert; cryptozoans typical. Thickness about 1,000 feet. |
| Ccr | Copper Ridge Dolomite | Ordovician | Copper Ridge Dolomite - Coarse, dark-gray, knotty dolomite, asphaltic in places; with much gray, medium-grained, well- bedded dolomite; abundant chert; cryptozoans typical. Thickness about 1,000 feet. |
| Ccu | Maynardville Limestone, Nolichucky Shale, and Honaker Dolomite | Cambrian | Maynardville
Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite) nodular
limestone; light-gray, fine-grained, laminated to thinly bedded, noncherty
dolomite in upper part. Thickness 150 to 400 feet; Nolichucky Shale -
Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly
oolitic, shaly limestone lenses; locally stromatolitic limestone layers;
thin, blocky siltstone near middle. Thickness 100 feet in the east to 900
feet in the west; Honaker Dolomite - Dark-gray, medium-bedded dolomite with
minor dark limestone beds; locally cherty; cryptozoans abundant in places.
Thickness about 1,500 feet. |
| Ce | Erwin Formation | Cambrian | Erwin Formation - White, vitreous quartzite, massive, with interbeds of dark-green silty and sandy shale, minor siltstone, and very fine-grained sandstone. Thickness 1,000 to 1,500 feet. |
| Ch | Hampton Formation | Cambrian | Hampton Formation - Dark greenish-gray, silty and sandy, micaceous shale; numerous layers of medium-grained, feldspathic, thinly bedded sandstone. Thickness 500 to 2,000 feet. |
| Che | Chilhowee Group; Hesse Sandstone | Cambrian | Chilhowee Group; Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Thickness about 600 feet. |
| Che | Hesse Sandstone | Cambrian | Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Thickness about 600 feet. |
| Chk | Honaker Dolomite | Cambrian | Honaker Dolomite - Dark-gray, medium-bedded dolomite with minor dark limestone beds; locally cherty; cryptozoans abundant in places. Thickness about 1,500 feet. |
| Cm | Maryville Limestone | Cambrian | Maryville Limestone - Gray, ribboned (silt and dolomite), fine-grained, evenly bedded limestone; intraformational conglomerate and oolitic layers common; clay shale and light-gray dolomite locally. Thickness 300 to 800 feet. |
| Cmn | Maynardville Limestone | Cambrian | Maynardville Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite), nodular limestone; light-gray, fine- grained, laminated to thin-bedded, noncherty dolomite in upper part. Thickness 150 to 400 feet. |
| Cmn | Maynardville Limestone | Cambrian | Maynardville Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite) nodular limestone; light-gray, fine-grained, laminated to thinly bedded, noncherty dolomite in upper part. Thickness 150 to 400 feet. |
| Cmr | Maryville, Rogersville, and Rutledge Formations | Cambrian | Maryville,
Rogersville, and Rutledge Formations - Maryville and Rutledge are gray
limestone, in part oolitic, with gray dolomite locally. Rogersville is green
clay shale. Thickness 400 to 1,000 feet. |
| Cmr | Maryville Limestone, Rogersville Shale, Rutledge Limestone | Cambrian | Maryville
Limestone - Gray, ribboned (silt and dolomite), fine-grained, evenly bedded
limestone; intraformational conglomerate and oolitic layers common; clay
shale and light-gray dolomite locally. Thickness 300 to 800 feet; Rogersville
Shale - Light-green, fissile clay shale; in places limestone (Craig Member)
in upper part. Commonly 25 to 80 feet thick; maximum thickness 250 feet;
Rutledge Limestone - Medium- to dark-gray, ribboned (silt and dolomite),
medium-grained, well-bedded limestone; locally dark-gray, coarse-grained,
medium-bedded dolomite in upper part. Thickness 100 to 500 feet. |
| Cmu | Chilhowee Group; Murray Shale | Cambrian | Chilhowee Group; Murray Shale - Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet. |
| Cmu | Murray Shale | Cambrian | Murray Shale - Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet. |
| Cn | Nolichucky Shale | Cambrian | Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 500 feet in the east to 900 feet in the west. |
| Cn | Nolichucky Shale | Cambrian | Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 100 feet in the east to 900 feet in the west. |
| Cnb | Chilhowee Group; Nebo Sandstone | Cambrian | Chilhowee Group; Nebo Sandstone - Medium-bedded, fine-grained, white vitreous quartzite, in part feldspathic. Thickness 250 feet. |
| Cnb | Nebo Sandstone | Cambrian | Nebo Sandstone - Medium-bedded, fine-grained, white, vitreous quartzite, in part feldspathic. Thickness 250 feet. |
| Cni | Nichols Shale | Cambrian | Chilhowee Group; Nichols Shale - Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet. |
| Cni | Nichols Shale | Cambrian | Nichols Shale - Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet. |
| Cpv | Pumpkin Valley Shale | Cambrian | Pumpkin Valley Shale - Dull-brown to maroon shale with numerous interbeds of thin, blocky, and sandy siltstone. Thickness 100 to 600 feet. |
| Cr | Rome Formation | Cambrian | Rome Formation - Variegated (red, green, yellow) shale and siltstone with beds of gray, fine-grained sandstone. Maximum exposed thickness 1,500 feet. |
| Cr | Rome Formation | Cambrian | Rome Foundation - Variegated (red, green, yellow) shale and siltstone; gray, fine-grained sandstone in middle and west part of Valley and Ridge; abundant limestone and dolomite in east. Thickness about 2,000 feet. |
| Crg | Rogersville Shale | Cambrian | Rogersville Shale - Light-green, fissile clay shale; in places limestone (Craig Member) in upper part. Commonly 25 to 80 feet thick; maximum thickness 250 feet. |
| Crt | Rutledge Limestone | Cambrian | Rutledge Limestone - Medium- to dark-gray, ribboned (silt and dolomite), medium-grained, well-bedded limestone; locally dark-gray, coarse-grained, medium-bedded dolomite in upper part. Thickness 100 to 500 feet. |
| Cs | Shady Dolomite | Cambrian | Shady Dolomite - Light-gray dolomite and thinly bedded limestone with much shaly gray limestone and calcareous gray shale. Thickness about 1,000 feet. |
| Cs | Shady Dolomite | Cambrian | Shady Dolomite - Light-gray, well-bedded dolomite with thin- to medium-bedded gray limestone; yellowish-brown residual clays with "jasperoid" diagnostic. Thickness about 1,000 feet. |
| Cu | Unicoi Formation | Cambrian | Unicoi Formation - Sequence of gray feldspathic sandstone, arkose, conglomerate, graywacke, siltstone and shale; greenish amygdaloidal basalt flows near middle and base. Thickness 2,000 to 5,000 feet. |
| D | Devonian Formations, includes Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation | Devonian | Devonian
Formations - Characterized by marked north-south facies variations. Because
of pre-Chattanooga and/or pre-Cretaceous warping and erosion, the
distribution and thickness of Devonian formations is very irregular. Includes Pegram Formation - Thick-bedded,
gray limestone and gray sandstone. Thickness 0 to 15 feet; Camden Formation -
Light-gray novaculitic chert and tripolitic clay; and minor siliceous
limestone. Thickness 0 to about 100 feet;
Harriman Formation - Light-gray novaculitic chert and tripolitic clay;
and minor siliceous limestone. (Harriman and Camden are differentiated
paleontologically.) Thickness 0 to 50 feet;
Flat Gap Limestone - Thick-bedded, coarse-grained limestone, gray with
red and brown grains. Thickness 0 to 55 feet;
Ross Formation - Siliceous limestone; gray and variegated shale; and
medium-grained glauconitic limestone. Thickness 0 to 75 feet. |
| D | Devonian Formations, including Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation | Devonian | Devonian
Formations - Characterized by marked north-south facies variations and by
very irregular distribution. Individual formations are not uniform in
thickness and have been truncated by pre-Chattanooga erosion; includes Pegram
Formation - Thick-bedded, gray limestone and gray sandstone. Thickness 0 to
30 feet; Camden Formation - Light-gray novaculitic chert and tripolitic clay;
and minor siliceous limestone. Thickness 0 to about 100 feet; Harriman Formation - Light-gray novaculitic
chert and tripolitic clay; and minor siliceous limestone. (Harriman and
Camden are differentiated paleontologically.) Thickness 0 to 50 feet; Flat Gap Limestone - Thick-bedded,
coarse-grained limestone, gray with red and brown grains. Thickness 0 to 13
feet; Ross Formation - Siliceous limestone; gray and variegated shale; and
medium-grained glauconitic limestone. Thickness 0 to 75 feet. |
| DSs | Sneedville Limestone | Devonian to Silurian | Sneedville Limestone - Gray silty limestone and dolomite, minor shale, and fine-grained, greenish-gray sandstone; fossils locally abundant. Thickness 100 to 300 feet. |
| ig | Intrusive igneous rocks | Paleozoic () | Intrusive Igneous Rocks - Metadiorite and metagabbro in Polk County, intrude Great Smoky Group. |
| ig | Intrusive igneous rocks | Precambrian | Intrusive Igneous Rocks - Mica peridotite plugs (two in Union County), intrude Sneedville Limestone; metadiorite and metagabbro sills and dikes in Sevier County, intrude Great Smoky Group. |
| Kc | Coffee Sand | Cretaceous | Coffee Sand - Loose fine-grained sand, light-gray, sparsely glauconitic, locally interbedded with laminated lignitic clay. Thickness 25 to 200 feet; thins northward. |
| Kc | Coffee Sand | Cretaceous | Coffee Sand - Loose fine-grained sand, light-gray, sparsely glauconitic; locally interbedded with laminated lignitic clay. Maximum preserved thickness about 40 feet. |
| Kcc | Coon Creek Formation | Cretaceous | Coon Creek Formation - Fossiliferous, micaceous sand, silty and glauconitic; locally fossiliferous sandy clay at base. Siderite concretions common in upper part. Thickness about 140 feet. |
| Kd | Demopolis Formation | Cretaceous | Demopolis Formation - Marl and calcareous clay, light-gray, fossiliferous, locally glauconitic and sandy. Merges northward into sands mapped as Kcc. Maximum thickness 180 feet. |
| Ke | Eutaw Formation | Cretaceous | Eutaw Formation - Grayish-green sand, fine-grained, glauconitic, micaceous; interbedded with gray laminated clays which commonly contain carbonized or silicified wood. (Mapped with Coffee except in Hardin County and southeastern Decatur County.) Thickness 0 to 180 feet; thins northward |
| Ke | Eutaw Formation | Cretaceous | Eutaw Formation - Grayish-green sand, fine-grained, glauconitic, micaceous; interbedded with gray laminated clays which commonly contain carbonized or silicified wood. Maximum preserved thickness 80 feet; absent to the north. |
| Km | McNairy Sand | Cretaceous | McNairy Sand - Predominantly sand, in places interbedded with silty light-gray clays. Fine-grained sand at base, locally contains heavy minerals. Thickness about 300 feet. |
| Ko | Owl Creek Formation | Cretaceous | Owl Creek Formation - Sandy clay, greenish gray, glauconitic, fossiliferous; merges northward into unfossiliferous clays and sands. Thickness 0 to about 40 feet. |
| Ks | Sardis Formation | Cretaceous | Sardis Formation - Quartz sand and glauconite sand, argillaceous and locally fossiliferous. (Mapped with Kcc north of Beech River.) Maximum thickness 70 feet. |
| Kt | Tuscaloosa Formation | Cretaceous | Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 140 feet. |
| Kt | Tuscaloosa Formation | Cretaceous | Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 150 feet. |
| Mbh | Bangor Limestone and Hartselle Formation | Mississippian | Bangor
Limestone - Dark brownish-gray limestone, thick-bedded. Thickness 100 to 250
feet; and Hartselle Formation - Thin-bedded, fine-grained sandstone and
greenish-gray shale interbedded with coarse limestone. Thickness 0 to 60
feet. |
| Mbh | Bangor Limestone and Hartselle Formation | Mississippian | 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. |
| MDc | Chattanooga Shale | Mississippian and Devonian | Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 20 to 30 feet in most areas; thickens abruptly to about 100 feet near east edge of sheet. (Mapped with Mfp on West-Central sheet) |
| MDc | Chattanooga Shale | Mississippian and Devonian | Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 100 to 900 feet; about 25 feet on Chilhowee Mountain. (Mapped with Mfp on West-Central and parts of East Central Sheets) |
| MDSO | Mississippian, Silurian, Devonian, and Ordovician Formations - containing all or portions of the Newman, Fort Payne, Chattanooga, Rockwood, and Sequatchie formations. | Mississippian to Ordovician | Mississippian,
Silurian, Devonian, and Ordovician Formations - Structurally complex area
containing all or portions of the Newman, Fort Payne, Chattanooga, Rockwood,
and Sequatchie formations. |
| Mfp | Fort Payne Formation | Mississippian | Fort Payne Formation - Bedded chert, calcareous and dolomitic, somewhat crinoidal; and minor shale. Thin green shale (Maury) at base. Average thickness about 200 feet. |
| Mfp | Fort Payne Formation | Mississippian | Fort Payne Formation - Bedded chert, calcareous and dolomitic, somewhat crinoidal; and minor shale. Thin green shale (Maury) at base. Thickness about 300 feet. |
| Mfp | Fort Payne Formation and Chattanooga Shale | Mississippian | Fort
Payne Formation - Bedded chert and calcereous and dolomitic silicastone;
minor coarse-grained limestone and shale. Thin green shale (Maury) at base.
Thickness about 200 feet. Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 0 to 70 feet. |
| Mfp | Fort Payne Formation and Chattanooga Shale | Mississippian | Fort
Payne Formation - Bedded chert; calcareous and dolomitic silicastone; minor
limestone and shale; scattered lenses of crinoidal limestone. Thin green
shale (Maury) at base. Average thickness about 250 feet (475 in Wells Creek
area); and Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 0
to 70 feet; average about 20 feet. (Mapped as MDc on East-Central and East sheets) |
| Mfp | Fort Payne Formation and Chattanooga Shale | Mississippian | Fort
Payne Formation - Calcareous and dolomitic silicastone; contains bedded
chert, cherty limestone, and shale; scattered crinoidal limestone lenses.
Thin green shale (Maury) at base. Thickness 100 to 275 feet.; and Chattanooga
Shale - Black carbonaceous shale, fissile. Thickness 20 to 30 feet in most
areas. (Mapped as MDc in Flynn Creek structure, where it is about 200 feet
thick.) (Also mapped as MDc on the
East Sheet) |
| Mg | Grainger Formation | Mississippian | Grainger Formation - Gray to green shale with siltstone and fine-grained glauconitic sandstone; in some areas quartz-pebble conglomerate. Thickness about 1,200 feet. |
| Mg | Grainger Formation | Mississippian | Grainger Formation - Gray to green shale with siltstone and fine-grained glauconitic sandstone; in some areas quartz-pebble conglomerate. Thickness 500 to 1,000 feet. |
| Mgg | Greasy Cove Formation, includes Grainger Formation | Mississippian | Greasy Cove Formation, includes Grainger Formation- Gray argillaceous limestone, calcareous shale, siltstone, and fine-grained sandstone. Equivalent to Newman Limestone. Maximum preserved thickness about 400 feet. |
| Mgg | Greasy Cove Formation and Grainger Formation | Mississippian | Greasy
Cove Formation - Gray, argillaceous limestone, calcareous shale, siltstone,
and fine-grained sandstone. Equivalent to Newman Limestone. Maximum preserved
thickness about 400 feet; and Grainger
Formation - Gray to green shale with siltstone and fine-grained glauconitic
sandstone; in some areas quartz-pebble conglomerate. Thickness about 1,200
feet. |
| Mm | Monteagle Limestone | Mississippian | Monteagle Limestone - Fragmental and oolitic limestone, light-gray; and fine-grained, brownish-gray limestone. Thickness 180 to 350 feet. |
| Mm | Monteagle Limestone | Mississippian | Monteagle Limestone - Mainly fragmental and oolitic, light-gray limestone; blocky bryozoan chert weathers from base. Thickness 180 to 300 feet. |
| Mn | Newman Limestone | Mississippian | Newman Limestone - Gray limestone sequence near Cumberland Plateau and on Whiteoak Mountain. Shaly limestone, shale, siltstone, and sandstone on Chilhowee Mountain. Thickness about 700 feet. |
| Mn | Newman Limestone | Mississippian | Newman Limestone - Gray limestone sequence near Cumberland Plateau; shaly and silty limestone with minor sandstone and shale in the area of Clinch Mountain. Thickness 600 to 3,000 feet. |
| Mp | Pennington Formation | Mississippian | Pennington Formation - Highly variegated clay shale, distinctive; contains siltstone and locally gray, fine-grained sandstone. Thickness 400 to 700 feet. |
| Mp | Pennington Formation | Mississippian | Pennington Formation - Highly variegated clay shale distinctive; contains siltstone beds and locally gray, fine-grained sandstone. Thickness 300 to 500 feet near Cumberland Plateau; maximum of about 1,250 feet to the east. |
| Mp | Pennington Formation | Mississippian | Pennington Formation - Reddish and greenish shale and siltstone; fine-grained dolomite; and minor fragmental and oolitic limestone. Thickness 240 to 360 feet. |
| Mp | Pennington Formation | Mississippian | Pennington Formation - Reddish and greenish shale and siltstone; fine-grained dolomite; dark-gray limestone; and thin-bedded sandstone. Persistent dolomite bed at base. Thickness 150 to 400 feet. |
| Msg | St. Genevieve Limestone | Mississippian | St. Genevieve Limestone - Gray limestone, slightly oolitic and cherty, with some green shale and fine-grained sandstone. Maximum preserved thickness 70 feet. (In Western Highland Rim area only.) |
| Msw | St. Louis Limestone and Warsaw Limestone | Mississippian | St.
Louis Limestone - Residuum of nodules and blocks of chert in sandy clay.
(Originally grayish-brown, medium-bedded limestone.) Maximum preserved
thickness about 50 feet. Warsaw Limestone - Residuum of porous chert blocks
in sandy clay. (Originally gray, medium- to coarse-grained, thick- bedded
limestone.) Thickness about 60 feet. |
| Msw | St. Louis Limestone and Warsaw Limestone | Mississippian | St.
Louis Limestone - Fine-grained, brownish-gray limestone, dolomitic and
cherty. Thickness 100 to 280 feet; and Warsaw Limestone - Coarse-grained,
gray, crossbedded limestone; somewhat shaly in the northeast. Thickness 40 to
150 feet. |
| Msw | St. Louis Limestone and Warsaw Limestone | Mississippian | 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. |
| O | Ordovician Formations including Richmond Group (Mannie Shale, Fernvale Limestone), and Nashville Group (Hermitage Formation) | Ordovician | Ordovician
Formations - Richmond Group (including Mannie Shale - Shale with thin beds of argillaceous limestone.
Thickness 0 to 20 feet and Fernvale Limestone - Thick-bedded, coarse-grained
limestone with vari-colored grains. Thickness 0 to 20 feet). and Nashville Group (including Hermitage Formation - Gray shale and thin-bedded to laminated, sandy and argillaceous limestone. Maximum exposed thickness 80 feet.) |
| O | Ordovician formations, including Mannie Shale, Fernvale Limestone, Hermitage Formation, and Carters, Lebanon, Ridley, Pierce, and Murfreesboro Limestones | Ordovician | Ordovician
formations - including Mannie Shale - Shale with thin beds of argillaceous
limestone. Thickness 0 to 20 feet; Fernvale Limestone - Thick-bedded, coarse-grained, gray limestone with
varicolored grains. Thickness 0 to 30 feet; Hermitage Formation - Gray shale
and thin-bedded to laminated, sandy and argillaceous limestone. About 200 to
300 feet thick in Wells Creek Basin; only about 80 feet exposed in Western
Valley; and the Carters, Lebanon, Ridley, Pierce, and Murfreesboro Limestones
- Thin- to thick-bedded, cryptograined to coarse-grained, yellowish-brown to
olive-gray limestones. Thickness about 1,000 feet. (Not exposed in Western
Valley.) |
| Oa | Athens Shale | Ordovician | Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet. |
| Oa | Athens Shale | Ordovician | Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet. |
| Ob | Bays Formation | Ordovician | Bays Formation - Maroon, well-jointed claystone and siltstone, commonly mottled greenish, evenly bedded; light- gray sandstone beds and metabentonite in upper part. Maximum thickness 1,000 feet. |
| Ob | Bays Formation | Ordovician | Bays Formation - Maroon claystone and siltstone, commonly mottled greenish, evenly bedded; to northeast, light- gray to white, thick-bedded sandstone; metabentonite in upper part. Maximum thickness 1,000 feet. |
| Obh | Nashville Group; Bigby-Cannon Limestone and Hermitage Formation | Ordovician | Nashville
Group - Bigby-Cannon Limestone - Brownish-gray phosphatic calcarenite and
light-gray to brownish-gray, cryptograined to medium- grained, even-bedded
limestone. Thickness 50 to 125 feet; and Hermitage Formation - Thin-bedded to
laminated, sandy and argillaceous limestone with shale; nodular shaly
limestone; coquina; and phosphatic calcarenite. Thickness 50 to 100
feet. |
| Obh | Bigby-Cannon Limestone and Hermitage Formation | Ordovician | Bigby-Cannon
Limestone - Dark- to light-gray, dense to medium-grained, medium- and
even-bedded limestone. Thickness 80 to 150 feet; and Hermitage Formation -
Gray, fine-grained, thin-bedded to laminated, sandy and argillaceous
limestone; shale, weathers yellowish-brown; and nodular, shaly limestone.
Thickness 50 to 100 feet. |
| Obr | Ordovician Breccia | Ordovician | Ordovician
Breccia - Angular to subrounded fragments of limestone ranging in size from a
fraction of an inch to several feet. um |
| Obr | Ordovician Breccia | Ordovician | Ordovician Breccia - Limestone and dolomite fragments ranging in size from a fraction of an inch to several feet. |
| Oc | Chepultepec Dolomite | Ordovician | Chepultepec Dolomite - Light-gray, fine-grained, well-bedded dolomite, moderately cherty; fine-grained limestone locally in upper part; quartz sandstone beds at base. Average thickness about 800 feet. |
| Oc | Chepultepec Dolomite | Ordovician | Chepultepec Dolomite - Light-gray, fine-grained, well-bedded dolomite, moderately cherty; fine-grained limestone locally in upper part; quartz sandstone beds at base. Thickness about 800 feet. |
| Oca | Stones River Group; Carters Limestone | Ordovician | Stones River Group; Carters Limestone - Fine-grained, yellowish-brown limestone; thin-bedded in upper part; thicker bedded and very slightly cherty with scattered mottlings of magnesian limestone in lower part. Contains thin bentonite beds. Thickness 50 to 100 feet. |
| Oca | Carters Limestone | Ordovician | Carters Limestone - Fine-grained, yellowish-brown limestone; thin-bedded in upper part; thicker bedded and very slightly cherty with scattered mottlings of magnesian limestone in lower part. Contains thin bentonite beds. Thickness 60 to 250 feet. |
| OCk | Knox Group, including Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, Chepultepec Dolomite, and Copper Ridge Dolomite | Ordovician to Cambrian | Knox Group - Siliceous dolomite and magnesian limestone sequence. Thickness 2,500 to 3,000 feet. |
| OCk | Knox Group | Ordovician to Cambrian | Knox Group - Siliceous, well-bedded dolomite and magnesian limestone in the central and northwest belts of the Valley. To the southeast, much dark limestone is present and the rocks are only sparsely cherty. Thickness about 3,000 feet. |
| OCk | Knox Group, including Jonesboro Limestone, Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, Chepultepec Dolomite, Copper Ridge Dolomite, Conococheague Limestone | Ordovician to Cambrian | Knox
Group, including (Ojb) Jonesboro Limestone - Dark bluish-gray, ribboned (silt
and dolomite) limestone; numerous interbeds of dark-gray dolomite; quartz
sandstone at base. Erosional unconformity at top. Thickness about 2,000 feet;
(On) Newala Formation; (Oma) Mascot Dolomite - Light-gray, fine-grained,
well-bedded cherty dolomite; mottled (red and green) dolomite characteristic;
interbeds of bluish-gray limestone in upper part; chert-matrix quartz
sandstone at base. Erosional unconformity at top. Thickness 350 to 800 feet;
(Ok) Kingsport Formation - Gray, fine-grained, sparingly cherty dolomite with
basal dense, gray limestone sequence. Thickness about 250 feet;
(Olv) Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded
dolomite; interbeds of gray limestone in upper part. Thickness about 300
feet; (Oc) Chepultepec Dolomite - Light-gray, fine-grained, well-bedded
dolomite, moderately cherty; fine-grained limestone locally in upper part;
quartz sandstone beds at base. Thickness about 800 feet; (Ccr) Copper Ridge Dolomite - Coarse,
dark-gray, knotty dolomite, asphaltic in places; with much gray,
medium-grained, well- bedded dolomite; abundant chert; cryptozoans typical.
Thickness about 1,000 feet.; (Ccc) Conococheague Limestone - Well-bedded,
ribboned (silt and dolomite), dark-gray limestone; interbeds of fine-grained,
light- to dark-gray dolomite; sparingly cherty; cryptozoans typical.
Thickness about 1,500 feet. |
| OCk | Wells Creek Dolomite and Knox Group | Ordovician | Wells
Creek Dolomite and Knox Group - Yellowish-gray and light olive-gray dolomite,
within partings of grayish-green shale, and pale- orange to yellowish-gray
limestone; thin- to thick-bedded, micrograined to coarse-grained. Present
only in Wells Creek Basin. Exposed thickness at least 600 feet. (Also mapped with Onc on East-Central
Sheet) |
| Och | 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 | Chickamauga
Group - 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) |
| Och | Chickamauga Group | Ordovician | Chickamauga Group - In the northwest predominantly a limestone sequence about 2,000 feet thick. Becomes progressively more clastic and thicker to the southeast. |
| Oh | Holston Formation | Ordovician | Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet. |
| Oh | Holston Formation | Ordovician | Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet. |
| Oj | Juniata Formation | Ordovician | Juniata Formation - Maroon, claystone, siltstone, and shale; uniformly bedded; some faint greenish mottling; less calcareous than Sequatchie Formation. Thickness about 300 feet. |
| Ojb | Jonesboro Limestone | Ordovician | Jonesboro Limestone - Dark bluish-gray, ribboned (silt and dolomite) limestone; numerous interbeds of dark-gray dolomite; quartz sandstone at base. Erosional unconformity at top. Thickness about 2,000 feet. |
| Ok | Kingsport Formation | Ordovician | Kingsport Formation - Gray, fine-grained, sparingly cherty dolomite with basal dense, gray limestone sequence. Thickness about 250 feet. |
| Ok | Kingsport Formation | Ordovician | Kingsport Formation - Gray, fine-grained, sparingly cherty dolomite with basal dense, gray limestone sequence. Thickness about 250 feet. |
| Ol | Lenoir Limestone | Ordovician | Lenoir Limestone - Nodular, argillaceous, gray limestone; in places basal sedimentary breccia, conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to medium-gray limestone) near base. Thickness 25 to 500 feet. |
| Ol | Lenoir Limestone | Ordovician | Lenoir Limestone - Nodular, argillaceous, gray limestone; in places basal sedimentary breccia, conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to medium-gray limestone) near base. Thickness 25 to 500 feet. |
| Olb | Stones River Group; Lebanon Limestone | Ordovician | Stones River Group; Lebanon Limestone - Thin-bedded, gray limestone with calcareous shale partings. Thickness 80 to 100 feet. |
| Olb | Lebanon Limestone | Ordovician | Lebanon Limestone - Thin-bedded limestone, gray to yellowish-brown, slightly dolomitic, with thin calcareous shale partings. Thickness about 100 feet. |
| Olc | Unnamed (middle part of Knox Group), including Longview Dolomite and Chepultepec Dolomite | Ordovician | (Olc)
Unnamed (middle part of Knox Group) including
(Olv) Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded
dolomite; interbeds of gray limestone in upper part. Thickness about 300
feet.; and (Oc) Chepultepec Dolomite - Light-gray, fine-grained, well-bedded
dolomite, moderately cherty; fine-grained limestone locally in upper part;
quartz sandstone beds at base. Average thickness about 800 feet. |
| Olc | Longview Dolomite and Chepultepec Dolomite | Ordovician | Longview
Dolomite - Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds
of gray limestone in upper part. Thickness about 300 feet; and Chepultepec
Dolomite - Light-gray, fine-grained, well-bedded dolomite, moderately cherty;
fine-grained limestone locally in upper part; quartz sandstone beds at base.
Thickness about 800 feet. |
| Olv | Longview Dolomite | Ordovician | Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in upper part. Thickness about 300 feet. |
| Olv | Longview Dolomite | Ordovician | Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in upper part. Thickness about 300 feet. |
| Oma | Mascot Dolomite | Ordovician | Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty dolomite; mottled (red and green) dolomite characteristic; interbeds of bluish-gray limestone in upper part; chert-matrix quartz sandstone at base. Erosional unconformity at top. Thickness 350 to 800 feet. |
| Oma | Mascot Dolomite | Ordovician | Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty dolomite; mottled (red and green) dolomite characteristic; interbeds of bluish-gray limestone in upper part; chert-matrix quartz sandstone at base. Erosional unconformity at top. Thickness 350 to 800 feet. |
| Omb | Martinsburg Shale, including Reedsville Shale and Unnamed Limestone Unit | Ordovician | Martinsburg
Shale - Bluish-gray, calcareous clay shale, weathers yellowish-brown; with
thin beds of nodular gray, fossiliferous limestone; thin layers of
metabentonite near base. Thickness about 1,000 feet. Incluldes Reedsville
Shale - Greenish-gray calcareous shale. Thickness 200 to 400 feet. and
Unnamed Limestone Unit - Medium-grained, fossiliferous, gray limestone, shaly
in part. Thickness as much as 600 feet. |
| Omlc | Middle and Lower parts of Chickamauga Group, including Moccassin Formation, Bays Formation, Sevier Shale, Ottosee Shale, Holston Formation, Lenoir Limestone, and Athens Shale | Ordovician | Middle
and Lower Parts of Chickamauga Group - A sequence of about 1,400 feet of
limestone in the northwest part of Valley and Ridge, which thickens and
becomes more clastic to the southeast and is divided into the formations
shown at right. Maximum thickness about 7,000 feet. Includes
Moccasin Formation - Maroon calcareous shale, siltstone, and
limestone; thin metabentonite layers in upper part; mud cracks, ripple marks
common. Thickness 800 to 1,000 feet;. (Ob) Bays Formation - Maroon,
well-jointed claystone and siltstone, commonly mottled greenish, evenly
bedded; light- gray sandstone beds and metabentonite in upper part. Maximum
thickness 1,000 feet; (Osv) Sevier Shale - Calcareous, bluish-gray shale,
weathers yellowish-brown; with thin, gray limestone layers; sandstone,
siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000
feet; (Oo) Ottosee Shale - Bluish-gray calcareous shale, weathers yellow;
with reef lenses of coarsely crystalline reddish fossiliferous limestone
("marble"). Thickness about 1,000 feet; (Oh) Holston Formation -
Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many
areas upper part is sandy, crossbedded ferruginous limestone and brown to
greenish calcareous shale. Thickness 200 to 600 feet; (Ol) Lenoir Limestone - Nodular,
argillaceous, gray limestone; in places basal sedimentary breccia,
conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to
medium-gray limestone) near base. Thickness 25 to 500 feet; (Oa) Athens Shale
- Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray
sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of
shaly limestone near base. Maximum thickness 1,500 feet. |
| Omlc | Middle and Lower Parts of Chickamauga Group, including Mocassin Formation, Bays Formation, Sevier Shale, Ottosee Shale, Holston Formation, Lenoir Limestone and Athens Shale | Ordovician | Middle
and Lower Parts of Chickamauga Group - A sequence of about 1,400 feet of
limestone in the northeast, which thickens and becomes more clastic to the
southeast and is divided into the formations shown at right. Maximum
thickness about 8,000 feet. Includes Mocassin Formation - Maroon calcareous shale, siltstone, and limestone; thin metabentonite layers in upper part; mud cracks, ripple marks common. Thickness 800 to 1,000 feet; (Ob) Bays Formation - Maroon claystone and siltstone, commonly mottled greenish, evenly bedded; to northeast, light- gray to white, thick-bedded sandstone; metabentonite in upper part. Maximum thickness 1,000 feet. (Osv) Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet; (Oo) - Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet; (Oh) - Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet; (Ol) Lenoir Limestone - Nodular, argillaceous, gray limestone; in places basal sedimentary breccia, conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to medium-gray limestone) near base. Thickness 25 to 500 feet; (Oa) Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet. |
| On | Newala Formation, including Mascot Dolomite and Kingsport Formation | Ordovician | (On)
Newala Formation, including (Oma)
Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty dolomite;
mottled (red and green) dolomite characteristic; interbeds of bluish-gray
limestone in upper part; chert-matrix quartz sandstone at base. Erosional
unconformity at top. Thickness 350 to 800 feet; and (Ok) Kingsport Formation
- Gray, fine-grained, sparingly cherty dolomite with basal dense, gray
limestone sequence. Thickness about 250 feet. |
| On | Newala Formation, including Mascot Dolomite and Kingsport Formation | Ordovician | Newala
Formation includes Mascot Dolomite - Light-gray, fine-grained, well-bedded
cherty dolomite; mottled (red and green) dolomite characteristic; interbeds
of bluish-gray limestone in upper part; chert-matrix quartz sandstone at
base. Erosional unconformity at top. Thickness 350 to 800 feet; and Kingsport Formation - Gray, fine-grained, sparingly cherty dolomite
with basal dense, gray limestone sequence. Thickness about 250 feet. |
| Onc | Unnamed (upper part of Knox Group), including Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, and Chepultepec Dolomite | Ordovician | (Onc) Unnamed
(upper part of the Knox Group), including the (On) Newala Formation;
(Oma) Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty
dolomite; mottled (red and green) dolomite characteristic; interbeds of
bluish-gray limestone in upper part; chert-matrix quartz sandstone at base.
Erosional unconformity at top. Thickness 350 to 800 feet; (Ok) Kingsport
Formation - Gray, fine-grained, sparingly cherty dolomite with basal dense,
gray limestone sequence. Thickness about 250 feet. and (Olc) Unnamed (middle part of the Knox Group), including (Olv) Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in upper part. Thickness about 300 feet; (Oc) Chepultepec Dolomite - Light-gray, fine-grained, well-bedded dolomite, moderately cherty; fine-grained limestone locally in upper part; quartz sandstone beds at base. Average thickness about 800 feet. |
| Onc | Jonesboro Limestone, Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, and Chepultepec Dolomite | Ordovician | Jonesboro
Limestone - Dark bluish-gray, ribboned (silt and dolomite) limestone;
numerous interbeds of dark-gray dolomite; quartz sandstone at base. Erosional
unconformity at top. Thickness about 2,000 feet; Newala Formation inlcuding
Mascot Dolomite - Light-gray, fine-grained, well-bedded cherty dolomite;
mottled (red and green) dolomite characteristic; interbeds of bluish-gray
limestone in upper part; chert-matrix quartz sandstone at base. Erosional
unconformity at top. Thickness 350 to 800 feet; and Kingsport Formation -
Gray, fine-grained, sparingly cherty dolomite with basal dense, gray
limestone sequence. Thickness about 250 feet; Longview Dolomite - Siliceous,
gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in
upper part. Thickness about 300 feet; Chepultepec Dolomite - Light-gray, fine-grained, well-bedded dolomite,
moderately cherty; fine-grained limestone locally in upper part; quartz
sandstone beds at base. Thickness about 800 feet. |
| Onc | Wells Creek Formation and Knox Group (above Copper Ridge Dolomite) | Ordovician | Wells
Creek Formation - Gray limestone and dolomite, with angular chert blocks and
fragments; and minor shale, mottled red and green, calcareous. Thickness 0 to
50 feet. (Present only in Sequatchie Valley.); and Knox Group (above Copper
Ridge Dolomite) - Gray, cherty dolomite and limestone, fine- to
medium-grained. Maximum exposed thickness in Sequatchie Valley 600 feet.
(Units in Onc are also mapped as OCk on the West-Central Sheet) |
| Oo | Ottosee Shale | Ordovician | Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet. |
| Oo | Ottosee Shale | Ordovician | Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet. |
| Opm | Stones River Group; Pierce Limestone and Murfreesboro Limestone | Ordovician | Stones
River Group; Pierce Limestone - Gray, thin-bedded limestone with shale
partings. Thickness 25 feet; and Murfreesboro Limestone - Thick-bedded,
dark-gray, fine-grained limestone, with mottlings of magnesian limestone;
somewhat cherty in upper part. Maximum exposed thickness 70 feet. |
| Opm | Pierce and Murfreesboro Limestones | Ordovician | Pierce and Murfreesboro Limestones - Medium- to very thick-bedded, fine-grained, gray limestone; thin-bedded, nodular and shaly, greenish-gray limestone in places. Thickness 200 to 500 feet. |
| Ord | Stones River Group; Ridley Limestone | Ordovician | Stones River Group; Ridley Limestone - Thick-bedded, brownish-gray limestone, fine-grained, with minor mottlings of magnesian limestone; slightly cherty. Thickness 90 to 150 feet. |
| Ord | Ridley Limestone | Ordovician | Ridley Limestone - Medium- to very thick-bedded, fine- to medium-grained, gray dolomitic limestone, with prominent greenish-gray calcareous shale and shaly limestone unit in middle. Thickness 200 to 275 feet. |
| Os | Sequatchie Formation | Ordovician | Sequatchie Formation - Maroon and gray shaly limestone, mottled greenish; with interbeds of calcareous, olive to maroon shale and siltstone. Average thickness about 200 feet. |
| Os | Sequatchie Formation | Ordovician | Sequatchie Formation - Maroon and gray shaly limestone, mottled greenish; with interbeds of olive to maroon calcareous shale and siltstone. Thickness about 300 feet. |
| Osv | Sevier Shale | Ordovician | Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin, gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet. |
| Osv | Sevier Shale | Ordovician | Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet. |
| Ou | Ordovician [units] including Richmond Group (which includes Mannie Shale, Fernvale Limestone, Sequatchie Formation, and Arnheim Formation), the Maysville Group (which includes Leipers Formation), the Eden Group (which includes Inman Formation), and the Nashville Group (which includes Catheys Formation) | Ordovician | Ordovician
[units] including Richmond Group
(which includes Mannie Shale - Olive-gray shale. Thickness 0 to 20 feet; Fernvale Limestone - Massive, coarsely
crystalline, gray limestone with varicolored grains. Thickness 0 to 50 feet;
Sequatchie Formation - Olive-gray and greenish-gray shale, mudstone, and
argillaceous limestone; dolomitic, laminated, and sandy. Thickness 0 to 100
feet; and Arnheim Formation Nodular, shaly, gray limestone. Thickness 0 to 20
feet; the Maysville Group (which includes Leipers Formation - Nodular, shaly
limestone; fine- to coarse-grained limestone; and phosphatic calcarenite
locally. Thickness 0 to 150 feet); the
Eden Group (which includes the Inman Formation - Thin-bedded to laminated,
fine-grained, gray limestone with shale partings. Thickness 0 to 50 feet);
and the Nashville Group (which includes Catheys Formation - Nodular, shaly
limestone; fine- to coarse-grained limestone; phosphatic calcarenite; and
light-gray cryptograined limestone. Thickness 50 to 175 feet.) |
| Ou | Sequatchie Formation, Leipers Formation, Inman Formation and Catheys Formation | Ordovician | Sequatchie
Formation - Greenish-gray calcareous shale, mudstone, and argillaceous
limestone; dolomitic, laminated, and sandy. Thickness 0 to 165 feet; Leipers Formation - Nodular, shaly
limestone and fine- to coarse-grained limestone. Thickness 0 to 150 feet;
Inman Formation - Thin-bedded to laminated, fine-grained, greenish-gray
limestone interbedded with red and green calcareous shale beds. Thickness 0
to 50 feet. (Present only in Sequatchie Valley.); and Catheys Formation -
Nodular, shaly, thin- to medium-bedded limestone and fine- to coarse-grained
limestone. Thickness 125 to 400 feet. |
| Pcf | Crooked Fork Group | Pennsylvanian | Crooked Fork Group - Shale, sandstone, siltstone, and thin coal beds; from top down group includes Poplar Creek coal, Wartburg Sandstone, Glenmary Shale, Coalfield Sandstone, Burnt Mill Shale, Crossville Sandstone, and Dorton Shale. Thickness 200 to 450 feet. |
| Pcf | Crooked Fork Group, including Wartburg Sandstone, Glenmary Shale, Coalfield Sandstone, Burnt Mill Shale, Crossville Sandstone, Dorton Shale | Pennsylvanian | Crooked
Fork Group - Shale, sandstone, conglomerate, siltstone, and coal; from Poplar
Creek coal to top of Rockcastle Conglomerate. Thickness 320 to 455 feet;
Wartburg Sandstone - Sandstone, gray to brown, fine- to medium-grained,
locally conglomeratic. Poplar Creek coal and thin shale at top. Thickness 0
to 50 feet; Glenmary Shale - Mostly dark-gray to light-brown shale with minor
siltstone and sandstone. Thin coal near base locally. Thickness 50 to 150
feet; Coalfield Sandstone - Sandstone, gray to brown, fine- to
medium-grained. Thickness 0 to 80 feet; Burnt Mill Shale - Mostly dark-gray to light-brown shale, with minor
siltstone. Thin sandstone locally present near base. Hooper coal just above
base. Thickness as much as 110 feet; Crossville Sandstone - Sandstone, gray
to brown or pink, fine- to medium-grained, thinly and evenly bedded.
Thickness 30 to 70 feet; Dorton Shale - Mostly dark-gray to light-brown
shale, with minor siltstone and sandstone. Thin coal near top. Rex coal as
much as 70 feet above base. Thickness as much as 150 feet. |
| Pcg | Crab Orchard Mounatins and Gizzard Group | Pennsylvanian | Crab
Orchard Mountains and Gizzard Groups - Sandstone, conglomerate, siltstone,
shale, and thin coal beds. From top down Crab Orchard Mountains group
includes Rockcastle Conglomerate, Vadever Formation, Newton Sandstone,
Whitwell Shale, and Sewanee Conglomerate; Gizzard Group includes Signal Point
Shale, Warren Point Sandstone, and Raccoon Mountain Formation. Thickness
about 1,200 to 1,400 feet. |
| Pcg | Crab Orchard Mountains and Gizzard Groups | Pennsylvanian | Crab
Orchard Mountains and Gizzard Groups - Sandstone, conglomerate, siltstone,
shale, and thin coal beds. Thickness 1,200 to 1,400 feet. |
| Pcm | Cross Mountain Formation | Pennsylvanian | Cross Mountain Formation - Mostly shale, interbedded with sandstone, siltstone, and thin coal beds; base at top of Frozen Head Sandstone. Maximum preserved thickness 270 feet. |
| Pcm | Cross Mountain Formation | Pennsylvanian | Cross Mountain Formation - Mostly shale, interbedded with sandstone, siltstone, and thin coal beds; base at top of Frozen Head Sandstone. Maximum preserved thickness 554 feet. |
| Pco | Crab Orchard Mountains Group | Pennsylvanian | Crab Orchard Mountains Group - Only the lowest formation of the group, the Sewanee Conglomerate, is preserved in the area of this sheet. Sewanee is gray to brown, medium- to coarse-grained conglomeratic sandstone, with a thin zone of ferruginous quartz- and shale-pebble conglomerate at base. Maximum preserved thickness 35 feet. |
| Pco | Crab Orchard Mountains Group, including Rockcastle Conglomerate, Vandever Formation, Newton Sandstone, Whitwell Shale, and Sewanee Conglomerate | Pennsylvanian | 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. |
| Pf | Fentress Formation | Pennsylvanian | 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. |
| Pg | Gizzard Group including Warren Point Sandstone and Raccoon Mountain Formation | Pennsylvanian | Gizzard
Group - Sandstone, conglomeratic sandstone, siltstone, shale, and minor coal.
Thickness 100 to 200 feet. Includes Warren Point Sandstone - Gray to brown
sandstone and minor conglomeratic sandstone. Thickness 60 to 160 feet; Raccoon Mountain Formation - Siltstone,
sandstone, shale, and minor coal. Thickness 0 to 65 feet. |
| Pg | Gizzard Group, including Signal Point Shale, Warren Point Sandstone, and Raccoon Mountain Formation | Pennsylvanian | 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. |
| Pgg | Graves Gap Formation | Pennsylvanian | Graves Gap Formation - Shale, sandstone, siltstone, and coal; from Windrock coal to top of Pioneer Sandstone. Thickness 200 to 350 feet. |
| Pgg | Graves Gap Formation | Pennsylvanian | Graves Gap Formation - Shale, sandstone, siltstone, and coal; from Windrock coal to top of Pioneer Sandstone. Thickness 275 to 385 feet. |
| Pib | Indian Bluff Formation | Pennsylvanian | Indian Bluff Formation - Shale, sandstone, siltstone, and thin coal beds; from Pioneer Sandstone Member to Jellico coal. Thickness 150 to 250 feet. |
| Pib | Indian Bluff Formation | Pennsylvanian | Indian Bluff Formation - Shale, sandstone, siltstone, and thin coal beds; from Pioneer Sandstone Member to Jellico coal. Thickness 150 to 415 feet. |
| Pr | Rockcastle Conglomerate | Pennsylvanian | 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. |
| Prm | Redoak Mountain Formation | Pennsylvanian | Redoak Mountain Formation - Shale, sandstone, siltstone, and several important coals; from Pewee coal to Windrock coal. Thickness 340 to 420 feet. |
| Prm | Redoak Mountain Formation | Pennsylvanian | Redoak Mountain Formation - Shale, sandstone, silicastone, and several important coals; from Pewee coal to Windrock coal. Thickness 340 to 420 feet. |
| Psl | Slatestone Formation | Pennsylvanian | Slatestone Formation - Shale, sandstone, siltstone, and several important coals; from Jellico coal to Poplar Creek coal. Thickness 500 to 650 feet. |
| Psl | Slatestone Formation | Pennsylvanian | Slatestone Formation - Shale, sandstone, siltstone, and several important coals; from Jellico coal to Poplar Creek coal. Thickness 500 to 720 feet. |
| Pvm | Vowell Mountain Formation | Pennsylvanian | Vowell Mountain Formation - Shale, sandstone, siltstone, and coal; from Frozen Head Sandstone Member to Pewee coal. Thickness 300 to 375 feet. |
| Pvm | Vowell Mountain Formation | Pennsylvanian | Vowell Mountain Formation - Shale, sandstone, siltstone, and coal; from Frozen Head Sandstone Member to Pewee coal. Thickness 230 to 375 feet. |
| pCb | Beech Granite | Precambrian | Beech Granite - Granite, porphyritic, light-gray to reddish; coarse potash feldspar crystals and clustered interstitial mafics (chloritized biotite and hornblende) give spotted appearance; includes Max Patch Granite. |
| pCba | Bakersville Gabbro | Precambrian | Bakersville Gabbro - Metagabbro, dark, porphyritic; contains diorite, basalt, anorthosite, and diabase; occurs as thin to massive dikes and lenticular masses. |
| pCc | Cranberry Granite | Precambrian | Cranberry Granite - Complex of intertonguing rock types including migmatite, granitic gneisses, monzonite, quartz diorite, greenstone, mica and hornblende schists, abundant granitic pegmatite. |
| pCca | Cades Sandstone | Precambrian | Cades Sandstone - Gray, well-bedded, fine- to medium-grained feldspathic metasandstone, with interbeds of dark slate and metasiltstone; precise stratigraphic position unknown. Thickness about 1,500 feet. |
| pCg | Great Smoky Group, including Anakeesta Formation, Thunderhead Sandstone, and Elkmont Sandstone | Precambrian | Great Smoky Group - Characterized by very massive layers of coarse graywacke and arkose. The formations have been mapped only in the region of the Great Smoky Mountains. Near Ducktown, in ascending order, the Copperhill, Hughes Gap, Hothouse, and Dean Formations are recognized. Thickness 14,000 to about 40,000 feet. Includes Anakeesta Formation - Dark-gray, bluish-gray, and black slate with dark-gray interbeds of fine-grained sandstone. Thickness 3,000 to 4,500 feet; Thunderhead Sandstone - Coarse, gray feldspathic sandstone, graywacke, and conglomerate; occurs in massive ledges; graded bedding and blue quartz characteristic. Thickness 5,500 to 6,300 feet; Elkmont Sandstone - Coarse to fine, gray feldspathic sandstone, graywacke, and fine conglomerate; generally finer grained beds in lower part; graded bedding typical. Thickness 1,000 to 8,000 feet |
| pCg | Great Smoky Group, includes Unnamed Sandstone Unit, Anakeesta Formation, Thunderhead Sandstone, and Elkmont Sandstone | Precambrian | Great
Smoky Group - Characterized by very massive layers of coarse graywacke and
arkose. The formations at right have been mapped only in region of the Great
Smoky Mountains. Thickness 14,000 to about 25,000 feet; includes Unnamed
Sandstone Unit - Gray, coarse sandstone and fine conglomerate, similar to
Thunderhead Sandstone. Thickness about 4,500 feet; Anakeesta Formation -
Dark-gray, bluish-gray, and black slate with dark-gray interbeds of
fine-grained sandstone. Thickness 3,000 to 4,500 feet; Thunderhead Sandstone
- Coarse, gray feldspathic sandstone, graywacke, and conglomerate; occurs in
massive ledges; graded bedding and blue quartz characteristic. Thickness
5,500 to 6,300 feet; Elkmont Sandstone - Coarse to fine, gray feldspathic
sandstone, graywacke, and fine conglomerate; generally finer grained beds in
lower part; graded bedding typical. Thickness 1,000 to 8,000 feet. |
| pCm | Mount Rogers Group including Bakersville Gabbro, Beech Granite, Cranberry Granite, and Roan Gneiss | Precambrian | Mount
Rogers Group - Metavolcanics, typically purplish and reddish; massive lavas
and tuffs, altered rhyolites and quartz latites; strongly foliated;
interbedded arkose, shale, and conglomerate. Thickness 1,000 to 3,000 feet;
Includes Bakersville Gabbro - Metagabbro, dark, porphyritic; contains
diorite, basalt, anorthosite, and diabase; occurs as thin to massive dikes
and lenticular masses; Beech Granite - Granite, porphyritic, light-gray to
reddish; coarse potash feldspar crystals and clustered interstitial mafics
(chloritized biotite and hornblende) give spotted appearance; includes Max
Patch Granite; Cranberry Granite - Complex of intertonguing rock types
including migmatite, granitic gneisses, monzonite, quartz diorite,
greenstone, mica and hornblende schists, abundant granitic pegmatite; and
Roan Gneiss - Layered hornblende and garnet gneiss and granitic migmatite
with zones of mica schist and amphibolite, foliation commonly contorted;
contains numerous granitic and gabbroic dikes. |
| pCo | Ocoee Supergroup, including Walden Creek Group, (including Sandsuck Formation, Wilhite Formation, Shields Formation, Licklog Formation), Cades Sandstone, and Rich Butt Sandstone | Precambrian | Ocoee
Supergroup - Terrigenous clastic sedimentary rocks, for the most part poorly
sorted and coarse. The groups are subdivided into formations only in the
region of the Great Smoky Mountains. Thickness as much as 50,000 feet.
Includes Walden Creek Group - The formations, other than the Sandsuck, have
been mapped only in the region of the Great Smoky Mountains. Thickness about
8,000 feet; Sandsuck Formation - Olive-green and gray, argillaceous,
micaceous shale with coarse feldspathic sandstone and quartz- pebble
conglomerate. Thickness about 2,000 feet; Wilhite Formation - Gray to green
siltstone and slate with interbeds of pebble conglomerate, sandstone, and
quartzite. Thickness about 4,000 feet; Shields Formation - Massive
conglomerate, sandstone, argillaceous slate; conglomerate (pebbles of various
rock types) characteristic. Thickness about 1,500 feet; Licklog Formation -
Feldspathic sandstone, greenish phyllite, and bluish-gray slate. Thickness
about 1,500 feet; and the Cades
Sandstone - Gray, well-bedded, fine- to medium-grained feldspathic
metasandstone, with interbeds of dark slate and metasiltstone; precise
stratigraphic position unknown. Thickness about 1,500 feet; and Rich Butt
Sandstone - Gray, massive beds of feldspathic, fine- to medium-grained
sandstone, with interbeds of dark slate and arkosic conglomerate; exact
stratigraphic position unknown. Thickness about 1,500 feet. |
| pCr | Roan Gneiss | Precambrian | Roan Gneiss - Layered hornblende and garnet gneiss and granitic migmatite with zones of mica schist and amphibolite, foliation commonly contorted; contains numerous granitic and gabbroic dikes. |
| pCrb | Rich Butt Sandstone | Precambrian | Rich Butt Sandstone - Gray, massive beds of feldspathic, fine- to medium-grained sandstone, with interbeds of dark slate and arkosic conglomerate; exact stratigraphic position unknown. Thickness about 1,500 feet. |
| pCs | Snowbird Group, including Pigeon Siltstone, Roaring Fork Sandstone, Metcalf Phyllite, Longarm Quartzite, and Wading Branch Formation | Precambrian | Snowbird
Group - The formations at right are applicable chiefly in the area of the
Great Smoky Mountains. Thickness 13,000 to about 20,000 feet. Includes Pigeon
Siltstone - Laminated, greenish quartzose and feldspathic siltstone; minor
fine-grained gray sandstone. Thickness as much as 10,000 feet; Roaring Fork
Sandstone - Interbedded massive feldspathic sandstone, greenish siltstone,
and greenish phyllite. Maximum thickness 7,000 feet; Metcalf Phyllite -
Lustrous, pale-green and silvery sericitic and chloritic phyllite; siltstone
interbeds abundant. Thickness uncertain; at least 5,000 feet; Longarm
Quartzite - Feldspathic quartzite and arkose, conspicuously light-colored,
current bedded and crossbedded. Thickness about 5,000 feet; Wading Branch
Formation - Medium- to dark-gray sandy slate to coarse, pebbly feldspathic
sandstone and graywacke; basal part is quartz-sericite phyllite; graded
bedding common. Thickness about 1,500 feet. |
| pCss | Walden Creek Group; Sandsuck Formation | Precambrian | Wladen Creek Group; Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet. |
| pCss | Sandsuck Formation | Precambrian | Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet. |
| pCw | Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation | Cambrian | Walden
Creek Group - The formations, other than the Sandsuck, are applicable mainly
in the region of the Great Smoky Mountains. Thickness about 8,000 feet,
Includes Sandsuck Formation - Olive-green and gray, argillaceous, micaceous
shale with coarse feldspathic sandstone and quartz- pebble conglomerate.
Thickness about 2,000 feet; Wilhite Formation - Gray to green siltstone and
slate with interbeds of pebble conglomerate, sandstone, and quartzite.
Thickness about 4,000 feet; Shields Formation - Massive conglomerate,
sandstone, argillaceous slate; conglomerate (pebbles of various rock types)
characteristic. Thickness about 1,500 feet.; Licklog Formation - Feldspathic
sandstone, greenish phyllite, and bluish-gray slate. Thickness about 1,500
feet. |
| pCw | Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation | Precambrian | The
formations, other than the Sandsuck, have been mapped only in the region of
the Great Smoky Mountains. Thickness about 8,000 feet. Includes Sandsuck Formation - Olive-green
and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and
quartz- pebble conglomerate. Thickness about 2,000 feet; Wilhite Formation -
Gray to green siltstone and slate with interbeds of pebble conglomerate,
sandstone, and quartzite. Thickness about 4,000 feet; Shields Formation -
Massive conglomerate, sandstone, argillaceous slate; conglomerate (pebbles of
various rock types) characteristic. Thickness about 1,500 feet; Licklog
Formation - Feldspathic sandstone, greenish phyllite, and bluish-gray slate.
Thickness about 1,500 feet. |
| Qal | Alluvial deposits | Quaternary | Alluvial Deposits - Sand, silt, clay, and gravel. In flood plain of Mississippi River more than 100 feet thick; in smaller streams generally less than 20 feet thick. |
| Qal | Alluvial deposits | Quaternary | Alluvial Deposits - Sand, silt, clay, and gravel. As much as 60 feet thick in flood plains of Tennessee and Cumberland Rivers; in smaller streams generally less than 20 feet thick. |
| Qal | Alluvial deposits | Quaternary | Alluvial Deposits - Sand, silt, clay and gravel. Mapped only in valley of Cumberland River and in Elk Valley. Thickness generally less than 30 feet. |
| Ql | Loess | Quaternary | Loess - Clayey and sandy silt, gray to brown, massive. Maximum thickness about 100 feet along bluffs of Mississippi River; thins eastward. (Minimum mapped thickness 4 feet.) |
| QT | High-level alluvial deposits | Quaternary-Tertiary | High-level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less then 60 feet thick. |
| QT | High-Level Alluvial Deposits | Quaternary-Tertiary | High-Level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less than 60 feet thick. |
| S | Silurian Formations, including Decatur Limestone, Brownsport Group (Lobelville Formation, Bob Limestone, Beech River Formation), Wayne Group (Dixon Formation, Lego Formation, Waldron Shale, Laurel Limestone, Osgood Formation) and Brassfield Limestone | Silurian | Silurian
Formations - A complete section of Silurian formations is not common because
of pre-Chattanooga and/or pre- Cretaceous erosion. Where preserved, Silurian
formations are remarkably uniform in thickness and are characteristically
light olive-gray to greenish-gray with variable reddish-brown color in some
area;. Decatur Limestone - Thick-bedded, medium- to coarse-grained limestone, gray with reddish-brown grains. Thickness 0 to 70 feet; Brownsport Group which includes 1) Lobelville Formation - Shale with thin beds of limestone. Thickness 0 to 40 feet; 2) Bob Limestone - Thick-bedded, medium-grained limestone, locally oolitic. Thickness 0 to 25 feet; and 3) Beech River Formation - Shale with thin beds of limestone. Thickness 0 to 60 feet; Wayne Group which includes: 1) Dixon Formation - Green and reddish-brown argillaceous limestone, shale, and mudstone. Thickness 0 to 40 feet; 2) Lego Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; 3) Waldron Shale - Greenish-gray fossiliferous shale. Thickness 0 to 5 feet; 4) Laurel Limestone - Even-bedded, gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; 5) Osgood Formation - Greenish- and reddish-gray shale and argillaceous limestone. Thickness 0 to 15 feet.; and Brassfield Limestone - Thin-bedded cherty limestone, locally glauconitic. Thickness 0 to 20 feet. |
| S | Silurian Formations, including Decatur Limestone, Brownsport Group (Lobelville Formation, Bob Limestone, Beech River Formation), Wayne Group (Dixon Formation, Lego Formation, Waldron Shale, Laurel Limestone, Osgood Formation) and Brassfield Limestone | Silurian | Silurian
Formations - Characteristically light olive-gray to greenish-gray, with
variable reddish-brown color in some areas. Individual formations are
generally uniform in thickness, except where truncated by pre- Chattanooga
erosion. Most formations are slightly thicker (than indicated) in Wells Creek
Basin. Includes Decatur Limestone- Thick-bedded, medium- to coarse-grained
limestone, gray with reddish-brown grains. Thickness 0 to 70 feet; Brownsport Group ( which includes
Lobelville Formation - Shale with thin beds of limestone. Thickness 0 to 30
feet; Bob Limestone - Thick-bedded, medium-grained limestone, locally
oolitic. Thickness 0 to 25 feet; and Beech River Formation - Shale with thin
beds of limestone. Thickness 0 to 60 feet); Wayne Group (which includes Dixon Formation - Green and reddish-brown argillaceous limestone, shale, and mudstone. Thickness 0 to 40 feet; Lego Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; Waldron Shale - Greenish-gray fossiliferous shale. Thickness 0 to 5 feet; Laurel Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; Osgood Formation - Greenish- and reddish-gray shale and argillaceous limestone. Thickness 0 to 15 feet); and Brassfield Limestone - Thin-bedded cherty limestone, locally glauconitic. Thickness 0 to 50 feet; generally about 20 feet. |
| S | Laurel Limestone, Osgood Formation, and Brassfield Formation | Silurian | Laurel
Limestone - Dolomitic limestone, mottled yellowish-gray to yellowish-green,
fine-grained. Thickness 0 to 10 feet. (Present only in Macon County); Osgood Formation - Grayish-green shale.
Thickness 0 to 10 feet. (Present only in Macon County.); and Brassfield
Formation - Olive-gray, fine-grained cherty limestone to the north, merging
into olive-gray calcareous shale to the south. Thickness 60 to 130 feet.
(Present only in Sequatchie Valley.) |
| Sc | Clinch Sandstone | Silurian | Clinch Sandstone - Clean, white, well-sorted sandstone; locally gray siltstone and shale. Average thickness about 600 feet. |
| Sr | Rockwood Formation | Silurian | Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 200 to 800 feet. |
| Sr | Rockwood Formation | Silurian | Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 350 to 550 feet. |
| Src | Rockwood Formation and Clinch Sandstone | Silurian | Rockwood
Formation - Brown to maroon shale, thin gray siltstone and sandstone, and
thin lenticular layers of oolitic and fossiliferous red hematite. Thickness
200 to 800 feet; and Clinch Sandstone - Clean, white, well-sorted sandstone;
locally gray siltstone and shale. Combined Rockwood and Clinch thicknesses
about 700 feet. |
| Src | Rockwood Formation and Clinch Sandstone | Silurian | Rockwood
Formation - Brown to maroon shale, thin gray siltstone and sandstone, and
thin lenticular layers of oolitic and fossiliferous red hematite. Thickness
350 to 550 feet; Clinch Sandstone - Clean, white, well-sorted sandstone;
locally gray siltstone and shale. Average thickness about 600 feet. |
| Tcw | Claiborne and Wilcox Formation | Tertiary | Claiborne and Wilcox Formations -- Irregularly bedded sand, locally interbedded with lenses and beds of gray to white clay, silty clay, lignitic clay, and lignite. Thickness more than 400 feet. |
| Tj | Jackson () Formation | Tertiary | Jackson () Formation - Sand, with layers of gray clay, silt, and lignite. Exposed only in bluffs along Mississippi River; thickness at least 60 feet. |
| Tm | Midway Group including Porters Creek Clay and Clayton Formation | Tertiary | Midway
Group - includes Porters Creek Clay - Pale-brown to brownish-gray, massive,
blocky clay; locally contains glauconitic sand. Thickness 130 to 170 feet.
Also includes Clayton Formation- Glauconitic sand, argillaceous and locally
fossiliferous; at base in Hardeman County is an impure fossiliferous
limestone. Thickness 30 to 70 feet. |
| WATR | water | Holocene | water |