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

Geologic units in Morgan county, Tennessee

[Additional scientific data in this geographic area]

Indian Bluff Formation (Pennsylvanian) at surface, covers 4 % of this area

Indian Bluff Formation - Shale, sandstone, siltstone, and thin coal beds; from Pioneer Sandstone Member to Jellico coal. Thickness 150 to 250 feet.

Lithology: shale; sandstone; siltstone; coal

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

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

Lithology: shale; siltstone; sandstone

Rockcastle Conglomerate (Pennsylvanian) at surface, covers 32 % of this area

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.

Lithology: conglomerate; sandstone; shale; coal

Crab Orchard Mounatins and Gizzard Group (Pennsylvanian) at surface, covers 0.5 % of this area

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.

Lithology: sandstone; conglomerate; shale; siltstone; coal

Vowell Mountain Formation (Pennsylvanian) at surface, covers 1 % of this area

Vowell Mountain Formation - Shale, sandstone, siltstone, and coal; from Frozen Head Sandstone Member to Pewee coal. Thickness 300 to 375 feet.

Lithology: shale; sandstone; siltstone; coal

Graves Gap Formation (Pennsylvanian) at surface, covers 2 % of this area

Graves Gap Formation - Shale, sandstone, siltstone, and coal; from Windrock coal to top of Pioneer Sandstone. Thickness 200 to 350 feet.

Lithology: shale; sandstone; siltstone; coal

Redoak Mountain Formation (Pennsylvanian) at surface, covers 2 % of this area

Redoak Mountain Formation - Shale, sandstone, siltstone, and several important coals; from Pewee coal to Windrock coal. Thickness 340 to 420 feet.

Lithology: shale; sandstone; siltstone; coal

Crooked Fork Group (Pennsylvanian) at surface, covers 42 % of this area

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.

Lithology: sandstone; shale; siltstone; coal

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

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

Lithology: limestone; shale; siltstone

Crab Orchard Mountains Group (Pennsylvanian) at surface, covers 4 % of this area

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.

Lithology: conglomerate; sandstone

Cross Mountain Formation (Pennsylvanian) at surface, covers 0.6 % of this area

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.

Lithology: shale; sandstone; siltstone; coal

Slatestone Formation (Pennsylvanian) at surface, covers 11 % of this area

Slatestone Formation - Shale, sandstone, siltstone, and several important coals; from Jellico coal to Poplar Creek coal. Thickness 500 to 650 feet.

Lithology: shale; sandstone; siltstone; coal

Gizzard Group including Warren Point Sandstone and Raccoon Mountain Formation (Pennsylvanian) at surface, covers < 0.1 % of this area

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.

Lithology: sandstone; shale; siltstone; coal