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

Geologic units in Obion county, Tennessee

[Additional scientific data in this geographic area]

Jackson (?) Formation (Tertiary) at surface, covers 0.9 % of this area

Jackson (?) Formation - Sand, with layers of gray clay, silt, and lignite. Exposed only in bluffs along Mississippi River; thickness at least 60 feet.

Lithology: sand; clay or mud; silt; lignite

Alluvium (Pleistocene to Holocene) at surface, covers < 0.1 % of this area

Alluvium; includes glacial deposits along the Ohio River and its tributaries west of Cannelton locks

Lithology: sand; silt; glacial drift

Continental deposits and loess, undifferentiated (Tertiary to Quaternary) at surface, covers 0.5 % of this area

Continental deposits and loess, undifferentiated; West of the Tennessee River

Lithology: loess; sand; gravel

Alluvial deposits (Quaternary) at surface, covers 24 % of this area

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.

Lithology: sand; silt; clay or mud; gravel

High-level alluvial deposits (Quaternary-Tertiary) at surface, covers 0.4 % of this area

High-level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less then 60 feet thick.

Lithology: gravel; sand; silt; clay or mud

Jackson and Claiborne Formations, undivided (Tertiary) at surface, covers < 0.1 % of this area

Jackson and Claiborne Formations, undivided; includes some rocks of Oligocene age

Lithology: sandstone; siltstone; shale

Loess (Quaternary) at surface, covers 74 % of this area

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.)

Lithology: silt