Geologic units in Blount county, Tennessee

Additional scientific data in this geographic area

Unnamed (upper part of Knox Group), including Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, and Chepultepec Dolomite (Ordovician) at surface, covers 11 % of this area

(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.

Great Smoky Group, includes Unnamed Sandstone Unit, Anakeesta Formation, Thunderhead Sandstone, and Elkmont Sandstone (Precambrian) at surface, covers 9 % of this area

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.

Sevier Shale (Ordovician) at surface, covers 8 % of this area

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.

Cades Sandstone (Precambrian) at surface, covers 7 % of this area

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.

Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation (Cambrian) at surface, covers 7 % of this area

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.

Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation (Precambrian) at surface, covers 6 % of this area

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.

Snowbird Group, including Pigeon Siltstone, Roaring Fork Sandstone, Metcalf Phyllite, Longarm Quartzite, and Wading Branch Formation (Precambrian) at surface, covers 4 % of this area

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.

Ottosee Shale (Ordovician) at surface, covers 4 % of this area

Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet.

Nolichucky Shale, and Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale (Cambrian) at surface, covers 4 % of this area

(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.

Knox Group, including Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, Chepultepec Dolomite, and Copper Ridge Dolomite (Ordovician to Cambrian) at surface, covers 4 % of this area

Siliceous dolomite and magnesian limestone sequence. Thickness 2,500 to 3,000 feet.

Jonesboro Limestone, Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, and Chepultepec Dolomite (Ordovician) at surface, covers 3 % of this area

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.

Knox Group, including Jonesboro Limestone, Newala Formation, Mascot Dolomite, Kingsport Formation, Longview Dolomite, Chepultepec Dolomite, Copper Ridge Dolomite, Conococheague Limestone (Ordovician to Cambrian) at surface, covers 3 % of this area

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.

Lenoir Limestone (Ordovician) at surface, covers 3 % of this area

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.

Copper Ridge Dolomite (Ordovician) at surface, covers 3 % of this area

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.

Maryville Limestone, Rogersville Shale, Rutledge Limestone (Cambrian) at surface, covers 2 % of this area

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.

Greasy Cove Formation and Grainger Formation (Mississippian) at surface, covers 2 % of this area

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.

Hesse Sandstone (Cambrian) at surface, covers 2 % of this area

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.

Athens Shale (Ordovician) at surface, covers 2 % of this area

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.

Copper Ridge Dolomite (Cambrian) at surface, covers 2 % of this area

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.

Holston Formation (Ordovician) at surface, covers 2 % of this area

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.

Nolichucky Shale (Cambrian) at surface, covers 1 % of this area

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.

Ottosee Shale (Ordovician) at surface, covers 1 % of this area

Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet.

Cochran Conglomerate (Cambrian) at surface, covers 1 % of this area

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.

Bays Formation (Ordovician) at surface, covers 0.9 % of this area

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.

Nebo Sandstone (Cambrian) at surface, covers 0.8 % of this area

Medium-bedded, fine-grained, white, vitreous quartzite, in part feldspathic. Thickness 250 feet.

Lenoir Limestone (Ordovician) at surface, covers 0.8 % of this area

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.

Rome Formation (Cambrian) at surface, covers 0.8 % of this area

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.

Shady Dolomite (Cambrian) at surface, covers 0.7 % of this area

Light-gray, well-bedded dolomite with thin- to medium-bedded gray limestone; yellowish-brown residual clays with "jasperoid" diagnostic. Thickness about 1,000 feet.

Nichols Shale (Cambrian) at surface, covers 0.7 % of this area

Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet.

Holston Formation (Ordovician) at surface, covers 0.6 % of this area

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.

Pumpkin Valley Shale (Cambrian) at surface, covers 0.6 % of this area

Dull-brown to maroon shale with numerous interbeds of thin, blocky, and sandy siltstone. Thickness 100 to 600 feet.

Murray Shale (Cambrian) at surface, covers 0.6 % of this area

Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet.

Maynardville Limestone (Cambrian) at surface, covers 0.5 % of this area

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.

Maynardville Limestone (Cambrian) at surface, covers 0.5 % of this area

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.

Sandsuck Formation (Precambrian) at surface, covers 0.4 % of this area

Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet.

Walden Creek Group; Sandsuck Formation (Precambrian) at surface, covers 0.3 % of this area

Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet.

Chepultepec Dolomite (Ordovician) at surface, covers 0.2 % of this area

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.

Chattanooga Shale (Mississippian and Devonian) at surface, covers 0.2 % of this area

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)

Ocoee Supergroup; Great Smokey Group, undivided (Late Proterozoic) at surface, covers < 0.1 % of this area

Thick metasedimentary sequence of massive to graded beds of metagraywacke and metasiltstone with interbedded graphitic and sulfidic slate and schist.

Longview Dolomite (Ordovician) at surface, covers < 0.1 % of this area

Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in upper part. Thickness about 300 feet.

Knox Group (Ordovician to Cambrian) at surface, covers < 0.1 % of this area

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.

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

Gray, fine-grained, sparingly cherty dolomite with basal dense, gray limestone sequence. Thickness about 250 feet.

Maynardville Limestone, Nolichucky Shale, and Honaker Dolomite (Cambrian) at surface, covers < 0.1 % of this area

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.

Ocoee Supergroup, Great Smokey Group; Boyd Gap Formation (Late Proterozoic) at surface, covers < 0.1 % of this area

Dark gray, highly-sulfidic slate and metasiltstone interbedded and gradational with metagraywacke. Stratigraphic position uncertain. In Cherokee County includes upper part of Buck Bald Formation.