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Mineral Resources > Online Spatial Data > Geology > by state > Georgia Geology

Geologic units in Floyd county, Georgia

[Additional scientific data in this geographic area]

Rome Formation (Cambrian) at surface, covers 4 % of this area

Rome Formation

Lithology: sandstone; shale

Conasauga Group; Middle unit; Limestone unit (Cambrian) at surface, covers 4 % of this area

Conasauga Group; Middle unit; Limestone unit: Includes limestone unit (Ccls), possible equivalent of Rutledge Limestone of Tennessee and shale unit (Cc), possible equivalent of Rogersville Shale of Tennessee

Lithology: limestone

Alluvial, coastal and low terrace deposits (Holocene) at surface, covers < 0.1 % of this area

Alluvial, coastal and low terrace deposits - Varicolored fine to coarse quartz sand containing clay lenses and gravel in places. Gravel composed of quartz and chert pebbles and assorted metmorphic and igneous rock fragments in streams near the Piedmont. In areas of the Valley and Ridge province gravel composed of angular to subrounded chert, quartz, and quartzite pebbles. Coastal deposits include fine to medium quartz sand with shell fragments and accessory heavy minerals along Gulf beaches and fine to medium quartz sand, silt, clay, peat, mud and ooze in the Mississippi Sound, Little Lagoon, bays, lakes, streams, and estuaries.

Lithology: beach sand; alluvium

Copper Ridge Dolomite (Cambrian) at surface, covers < 0.1 % of this area

Copper Ridge Dolomite

Lithology: dolostone (dolomite)

Conasauga Group; Upper unit; limestone and shale unit (Cambrian) at surface, covers 15 % of this area

Conasauga Group; Upper unit; limestone and shale unit: Includes limestone and shale unit (Ccsl). Possible equivalent of the Maryville Limestone and Nolichucky Shale of Tennessee with a dolostone member (Ccd).

Lithology: shale; limestone

Fort Payne Shale; Lavender Shale Member (Mississippian) at surface, covers 3 % of this area

Fort Payne Shale (Mfp) with Lavender Shale Member (Mls)

Lithology: shale

Newala Limestone (Ordovician) at surface, covers < 0.1 % of this area

Newala Limestone

Lithology: limestone

Conasauga Formation (Cambrian) at surface, covers < 0.1 % of this area

Conasauga Formation - Medium-bluish-gray fine-grained, thin-bedded argillaceous limestone and interbedded dark-gray shale in varying proportions.

Lithology: limestone; shale

Bangor Limestone (Mississippian) at surface, covers 0.6 % of this area

Bangor Limestone

Lithology: limestone

Floyd Shale (Mississippian) at surface, covers < 0.1 % of this area

Floyd Shale - Dark-gray shale, sideritic in part; thin beds of sandstone, limestone and chert are locally present; beds of partly bioclastic, partly argillaceous limestone are abundant in parts of Calhoun and Cherokee Counties.

Lithology: shale; sandstone; limestone; chert

Conasauga Group; Lower unit; shale and sandstone unit (Cambrian) at surface, covers 3 % of this area

Conasauga Group; Lower unit; shale and sandstone unit: Includes shale and sandstone unit (Ccs) with lower dolostone unit (Ccdl). Possible equivalent of Pumpkin Valley Shale of Tennessee

Lithology: shale; sandstone

Shady Dolomite (Cambrian) at surface, covers 0.4 % of this area

Shady Dolomite

Lithology: dolostone (dolomite)

Armuchee Chert (Devonian) at surface, covers 2 % of this area

Armuchee Chert

Lithology: chert

Floyd Shale (Mississippian) at surface, covers 17 % of this area

Floyd Shale (Mfs): includes the Hartselle Sandstone Member (Mh) in Floyd County and an unnamed limestone member (Ml in Floyd County) at the base

Lithology: shale

Rome Formation (Cambrian) at surface, covers < 0.1 % of this area

Rome Formation - variegated thinly interbedded mudstone, shale, siltstone, and sandstone; limestone and dolomite occur locally. Quartzose sandstone commonly present near top of formation.

Lithology: mudstone; shale; siltstone; sandstone; limestone; dolostone (dolomite)

Chickamauga Group; Upper and Middle Ordovician Rocks (Omb) includes Moccasin Limestone and Bays Formation (Ordovician) at surface, covers 0.9 % of this area

Chickamauga Group; Upper and Middle Ordovician Rocks (Omb) includes Moccasin Limestone and Bays Formation.

Lithology: limestone; sandstone

Conasauga Group; Maynardville Limestone (Cambrian) at surface, covers 0.4 % of this area

Conasauga Group; Maynardville Limestone

Lithology: limestone

Red Mountain Formation (Silurian) at surface, covers 5 % of this area

Red Mountain Formation

Lithology: sandstone; shale

Pennsylvanian undifferentiated (Pennsylvanian) at surface, covers 0.7 % of this area

Pennsylvanian undifferentiated

Lithology: sandstone; shale; conglomerate

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

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

Lithology: limestone; chert; siltstone; shale; claystone

Floyd Shale; unnamed limestone member (Mississippian) at surface, covers 0.5 % of this area

Floyd Shale; unnamed limestone member (Ml in Floyd County) at the base

Lithology: shale; limestone

Fort Payne Chert (Mississippian) at surface, covers 2 % of this area

Fort Payne Chert (Mfp) with Lavender Shale Member (Mls)

Lithology: chert

Conasauga Group; Upper unit; Dolostone member (Cambrian) at surface, covers 2 % of this area

Conasauga Group; Upper unit; Dolostone member: Includes limestone and shale unit (Ccsl). Possible equivalent of the Maryville Limestone and Nolichucky Shale of Tennessee with a dolostone member (Ccd).

Lithology: dolostone (dolomite)

Conasauga Group; Middle unit; Shale unit (Cambrian) at surface, covers 7 % of this area

Conasauga Group; Middle unit; Shale unit: Includes limestone unit (Ccls), possible equivalent of Rutledge Limestone of Tennessee and shale unit (Cc), possible equivalent of Rogersville Shale of Tennessee

Lithology: shale; limestone

Chickamauga Group; Upper and Middle Ordovician rocks (Oum) includes Sequatchie Limestone, Murfreesboro Limestone, Ridley Limestone, Moccasin Limestone and Bays Formation. (Ordovician) at surface, covers 1 % of this area

Chickamauga Group; Upper and Middle Ordovician rocks (Oum) includes Sequatchie Limestone, Murfreesboro Limestone, Ridley Limestone, Moccasin Limestone and Bays Formation.

Lithology: limestone

Knox Group undifferentiated (Ordovician-Cambrian) at surface, covers 26 % of this area

Knox Group undifferentiated

Lithology: dolostone (dolomite); limestone

Devonian-Missisippian undivided (Devonian-Mississippian) at surface, covers 3 % of this area

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

Lithology: shale ; chert

High terrace deposits (Pleistocene) at surface, covers < 0.1 % of this area

High terrace deposits - Varicolored lenticular beds of poorly sorted sand, ferruginous sand, silt, clay, and gravelly sand. Sand consists primarily of very fine to very coarse poorly sorted quartz grains; gravel composed of quartz, quartzite, and chert pebbles.

Lithology: terrace

Floyd Shale; Hartselle Sandstone member (Mississippian) at surface, covers 1 % of this area

Hartselle Sandstone member (Mh) in Floyd County

Lithology: sandstone

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

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

Lithology: sandstone; shale; siltstone; limestone