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Devonian Formations, including Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation

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.
State Tennessee
Name Devonian Formations, including Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation
Geologic age Devonian
Comments West-Central sheet
Primary rock type limestone
Secondary rock type chert
Other rock types clay or mud; shale; sandstone
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone
Minor
Sedimentary > Chemical > Chert
Unconsolidated > Fine-detrital > Clay
Incidental
Sedimentary > Clastic > Sandstone
Sedimentary > Clastic > Mudstone > Shale
Map references
Geology available at Tennesse Spatial Data Server which can be found at http://www.tngis.org/geology.html which links to a USGS Water Resources Division site: http://water.usgs.gov/lookup/getspatial?geo250k Tennessee Spatial Data Server site notes: Thanks goes to Jim Julian for researching this improved geology layer from the Tennessee Division of Geology. **Note** - The Tennessee Division of Geology does not endorse this coverage, stating this version is still incomplete and not fit for distribution.
Unit references
Geology available at Tennesse Spatial Data Server which can be found at http://www.tngis.org/geology.html which links to a USGS Water Resources Division site: http://water.usgs.gov/lookup/getspatial?geo250k Tennessee Spatial Data Server site notes: Thanks goes to Jim Julian for researching this improved geology layer from the Tennessee Division of Geology. **Note** - The Tennessee Division of Geology does not endorse this coverage, stating this version is still incomplete and not fit for distribution.
Hardeman, W.D., and others, 1966, Geologic map of Tennessee: Division of Geology, Tennessee Department of Environment and Conservation, scale 1:250,000