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

Geologic units in Tippah county, Mississippi

Demopolis chalk (Upper Cretaceous) at surface, covers < 0.1 % of this area

Demopolis chalk - (Selma group), Chalk and marly chalk containing fewer impurities than underlying and overlying formations.

Lithology: carbonate

High-level alluvial deposits (Quaternary-Tertiary) at surface, covers < 0.1 % 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

Midway Group including Porters Creek Clay and Clayton Formation (Tertiary) at surface, covers < 0.1 % of this area

Midway Group - includes Porters Creek Clay - Pale-brown to brownish-gray, massive, blocky clay; locally contains glauconitic sand. Thickness 130 to 170 feet. Also includes Clayton Formation- Glauconitic sand, argillaceous and locally fossiliferous; at base in Hardeman County is an impure fossiliferous limestone. Thickness 30 to 70 feet.

Lithology: clay or mud; sand; limestone

Alluvial deposits (Quaternary) at surface, covers < 0.1 % 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

Ripley formation (Upper Cretaceous) at surface, covers 18 % of this area

Ripley formation - (Selma group), gray to greenish-gray fine glauconitic sand, clay, and sandy limestone; south of Oktibbeha County is very sandy micaceous chalk.

Lithology: sand; clay or mud; limestone; mixed clastic/carbonate

Ripley formation (McNairy sand member) (Upper Cretaceous) at surface, covers 21 % of this area

Ripley formation (McNairy sand member) - (Selma group), red and white cross-bedded micaceous sand and white sandy clay.

Lithology: sand; clay or mud

Owl Creek Formation (Cretaceous) at surface, covers < 0.1 % of this area

Owl Creek Formation - Sandy clay, greenish gray, glauconitic, fossiliferous; merges northward into unfossiliferous clays and sands. Thickness 0 to about 40 feet.

Lithology: clay or mud; sand

Tallahatta formation and Neshoba sand (Eocene) at surface, covers 0.5 % of this area

Tallahatta formation and Neshoba sand - (Claiborne group), Southeast of Pearl River predominantly more or less glauconitic claystone and clay with lenses of sand and some sandstone; highly cross-bedded sand at base; northwest of Pearl river predominantly sand, locally glauconitic, containing claystone and clay lenses and abundant clay stringers; Neshoba sand, sparingly glauconitic fairly coarse sand not recognized southeast of Newton County or north of Yalobusha River.

Lithology: claystone; clay or mud; sand; sandstone

Claiborne and Wilcox Formation (Tertiary) at surface, covers 0.1 % of this area

Claiborne and Wilcox Formations -- Irregularly bedded sand, locally interbedded with lenses and beds of gray to white clay, silty clay, lignitic clay, and lignite. Thickness more than 400 feet.

Lithology: sand; clay or mud; lignite

Porters Creek formation (Paleocene) at surface, covers 26 % of this area

Porters Creek formation - (Midway group), Dark-gray clay, north of Clay County contains slightly glauconitic, micaceous sand lenses.

Lithology: clay or mud; sand

Prairie Bluff chalk and Owl Creek formation (Upper Cretaceous) at surface, covers 7 % of this area

Prairie Bluff chalk and Owl Creek formation - (Selma group), Prairie Bluff chalk, compact brittle chalk, sandy chalk, and calcareous clay; at base contains many phosphatic molds of fossils; in Ponotoc and Union Counties merges northward into Owl Creek formation, tough blue glauconitic sandy clay.

Lithology: carbonate; clay or mud; mixed clastic/carbonate

Clayton formation (Paleocene) at surface, covers 19 % of this area

Clayton formation - (Midway group), Upper part, greenish-gray coarsely glauconitic sandy clay and marl; lower part, crystalline sandy limestone and loose sand, represented south of Houston by a discontinuous bed of indurated calcareous sandstone.

Lithology: limestone; sand; clay or mud; calcarenite

Wilcox formation (Eocene) at surface, covers 8 % of this area

Wilcox formation - Irregularly bedded fine to coarse sand, more or less lignitic clay and lignite; includes bauxite bearing Fearn Springs sand member at base.

Lithology: clay or mud; sand; coal