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

Geologic units in Bienville Parish, Louisiana

Upper Cretaceous (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

fossiliferous limestone and marl

Lithology: limestone; unconsolidated deposit

Cane River Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 4 % of this area

brown silty clay with basal glauconitic, fossiliferous silts which may weather to ironstone locally.

Lithology: clay or mud; silt

Midway Group (undifferentiated) (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers < 0.1 % of this area

dark gray to black shale

Lithology: shale

Sparta Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 33 % of this area

white to light gray massive sands with interbedded clays; some thin beds of lignite or lignitic sands and shales.

Lithology: sandstone; clay or mud; coal

Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 5 % of this area

light gray to light brown clay, sandy clay, silt, sand, and some gravels.

Lithology: clay or mud; silt; sand; gravel

Cockfield Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 1 % of this area

brown lignitic clays, silts and sands; some sideritic glauconite may weather to brown ironstone in lower part.

Lithology: clay or mud; silt; sand

Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 7 % of this area

light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.

Lithology: clay or mud; silt; sand; gravel

Natural Levees (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.2 % of this area

gray and brown silt, silty clay, some very fine sand, reddish brown along the Red River.

Lithology: silt; clay or mud; sand

Wilcox Group (undifferentiated) (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 4 % of this area

gray to brown lignitic sands and silty to sandy lignitic clays, many seams of lignite; some limestone and glauconite.

Lithology: sand; clay or mud; coal; limestone

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 21 % of this area

gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.

Lithology: clay or mud; sand; gravel

High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 8 % of this area

tan to orange clay, silt, and sand with a large amount of basal gravels.

Lithology: clay or mud; silt; sand; gravel

Cook Mountain Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 15 % of this area

greenish gray sideritic clay in upper part may weather to brown ironstone; yellow to brown clays and fossiliferous marl in lower part may weather to black soil. Ironstone concretions near base.

Lithology: clay or mud; unconsolidated deposit