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

Geologic units in Louisiana (state in United States)

[Additional scientific data in this geographic area]

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 23 % 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

Lena Member (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

gray calcareous clays which may weather to black soil; siltstone, taffaceous clays and some volcanic ash beds

Lithology: clay or mud; siltstone; volcanic ash

Weches Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Weches Formation

Lithology: sand; clay or mud

Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 4 % 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

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvium - Alluvial deposits of present streams

Lithology: alluvium

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

Alluvium - Loam, sand, gravel, and clay; mapped only in Mississippi River Alluvial Plain.

Lithology: alluvium

Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 12 % of this area

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

Lithology: clay or mud; silt; sand; gravel

Cook Mountain Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 2 % 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

Carnahan Bayou Member (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 0.6 % of this area

yellow to gray siltstones, sandstones, and clays with thin tuffaceous beds; some lenses of black chert gravel; petrified wood locally.

Lithology: siltstone; sandstone; clay or mud; tuff; gravel

Natural Levees (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 14 % 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

Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 2 % of this area

light gray, tan and brown fine to coarse sand; some clay silt and gravel.

Lithology: sand; clay or mud; silt; gravel

Citronelle formation (Pleistocene) at surface, covers < 0.1 % of this area

Citronelle formation - Red sand and gravel and white clay; may be of Pliocene age; the formation mapped is equivalent to the Willis sand and does not include the terrace deposits, colluvium, and residuum commonly considered "Citronelle".

Lithology: sand; gravel; clay or mud

Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 3 % of this area

light gray to light brown clay, sandy clay, silt, sand, and some gravels. Overlain by 1-9 meters of loess.

Lithology: clay or mud; silt; sand; gravel

Delta Plain, Saline Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 4 % of this area

gray to black clay of very high organic content, some peat.

Lithology: clay or mud; peat

Cane River Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.3 % of this area

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

Lithology: clay or mud; silt

Cockfield Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 5 % 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

Delta Plain, Fresh Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 3 % of this area

gray to black clay of very high organic content, some peat.

Lithology: clay or mud; peat

Unknown (Unknown) at surface, covers < 0.1 % of this area

Lithology: indeterminate

Alluvium - Alluvial deposits of local streams or of overbank flow of major streams (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvial deposits of local streams or of overbank flow of major streams - In some areas includes deposits in abandoned meanders of major streams

Lithology: alluvium

High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 6 % of this area

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

Lithology: clay or mud; silt; sand; gravel

High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 1 % of this area

tan to orange clay, silt, and sand with a large amount of basal gravels. Overlain by 1-9 meters of loess.

Lithology: clay or mud; silt; sand; gravel

Chenier Plain, Saline Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 2 % of this area

gray to brown to black clay and silt of moderate organic content.

Lithology: clay or mud; silt

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

light gray to brown liginitic clays with thin interbeds of limonitic sands or lignite; near base,calcareous, glauconitic, and fossiliferous beds may weather to black soil. Overlain by 1-9 meters of loess.

Lithology: clay or mud; sand; coal

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

fossiliferous limestone and marl

Lithology: limestone; unconsolidated deposit

Sparta Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 1 % 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

Deweyville Terrace (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 0.7 % of this area

gray mixed with brown-to-red clay and silty clay; some sand and gravel locally.

Lithology: clay or mud; sand; gravel

Deweyville Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene (?)) at surface, covers < 0.1 % of this area

Deweyville Formation

Lithology: sand; silt; clay or mud

Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 1 % of this area

light gray, tan and brown fine to coarse sand; some clay silt and gravel. Overlain by 1-9 meters of loess.

Lithology: sand; clay or mud; silt; gravel

Catahoula Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.5 % of this area

gray to white sandstones; loose quartz sand, tuffaceous sandstone, volcanic ash, and brown sandy clays; petrified wood locally.

Lithology: sandstone; sand; volcanic ash

Jackson Group (undifferentiated) (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.5 % of this area

light gray to brown liginitic clays with thin interbeds of limonitic sands or lignite; near base,calcareous, glauconitic, and fossiliferous beds may weather to black soil.

Lithology: clay or mud; sand; coal

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers < 0.1 % of this area

Terrace deposits - Alluvial deposits on one or more terrace levels

Lithology: alluvial terrace

Reklaw Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Reklaw Formation

Lithology: sandstone; clay or mud

Claibourne Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers < 0.1 % of this area

Claibourne Group

Lithology: sand; clay or mud; coal

Chenier Plain, Fresh Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 2 % of this area

gray to brown to black clay and silt of high organic content.

Lithology: clay or mud; silt

Vicksburg Group (undifferentiated) (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.2 % of this area

brown to gray liginitic clays with thin interbeds of lignite or micaceous sands; calcareous shale, petrified wood, and bluish fossilferous clay locally.

Lithology: clay or mud; coal; sand; shale

Pascagoula and Hattiesburg formation (Miocene) at surface, covers < 0.1 % of this area

Pascagoula and Hattiesburg formation - Green and bluish-green clay, sandy clay, and sand; gray siltstone and sand; locally fossiliferous.

Lithology: clay or mud; sand; siltstone

Dough Hills Member (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 0.2 % of this area

gray to yellow silty clays; light gray calcareous clays which may weather to black soil; some siliceous silt and volcanic ash beds.

Lithology: clay or mud; silt; volcanic ash

alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

alluvium

Lithology: sand; silt; clay or mud; gravel

Williamson Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 0.2 % of this area

white to gray silts, siltstones, silty clays, and sand beds; some lenses of black chert gravel.

Lithology: silt; siltstone; clay or mud; sand; gravel

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

sand, silt, clay, and gravel. locally indurated with calcium carbonate (caliche); includes point bar, natural levee, stream channel, sand dune, terrace, alluvial fan, landslide bolson and playa deposits

Lithology: sand ; silt ; clay or mud; gravel; carbonate

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers < 0.1 % of this area

Terrace deposits

Lithology: terrace; sand; gravel; silt; clay or mud

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

dark gray to black shale

Lithology: shale

Blounts Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene Pliocene) at surface, covers 0.2 % of this area

gray to green silty clays, siltstones, and silts with abundant sand beds; some lignite and lenses of black chert gravel.

Lithology: mudstone; sand; coal; gravel

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

brown to gray liginitic clays with thin interbeds of lignite or micaceous sands; calcareous shale, petrified wood, and bluish fossilferous clay locally. Overlain by 1-9 meters of loess.

Lithology: clay or mud; coal; sand; shale

Queen City Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Queen City Sand

Lithology: sandstone; siltstone; 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

Castor Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 0.3 % of this area

gray to dark gray calcareous clays which may weather to black soil; lignitic clays and noncalcreous clayey silts

Lithology: clay or mud; silt

Wilcox Group, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers < 0.1 % of this area

Wilcox Group, undivided

Lithology: fine-grained mixed clastic; coal; sand; clay or mud

Alluvium - Alluvial deposits in major stream channels or in mappable meanders of major streams (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvial deposits in major stream channels or in mappable meanders of major streams - Includes alluvial deposits in natural levees in some areas.

Lithology: alluvium

Catahoula formation (Miocene) at surface, covers < 0.1 % of this area

Catahoula formation - Irregularly bedded gray sand and sandstone; mottled red and gray, green, and chocolate-colored clay; some quartzite, and some gravel; the Paynes Hammock sand, sandy limestone cross-bedded fine green sand, and thin-bedded sand and clay, is mapped with the underlying Chickasawhay limestone in eastern MS.

Lithology: sand; sandstone; clay or mud; quartzite; gravel

Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 0.5 % of this area

light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally. Overlain by 1-9 meters of loess.

Lithology: clay or mud; silt; sand; gravel

Vicksburg group and Chickasawhay limestone (Oligocene) at surface, covers < 0.1 % of this area

Vicksburg group and Chickasawhay limestone - Chickasawhay limestone, sandy limestone, and sand, present only in eastern MS (mapped with it is the overlying Paynes Hammock sand of Miocene age); Vicksburg group, predominantly limestone and marl, but contains some bentonite and near the top, chocolate-colored clay and some sand.

Lithology: limestone; sand; bentonite; clay or mud

Coastal deposits (Holocene) at surface, covers < 0.1 % of this area

Coastal deposits - Loam, sand, gravel and clay.

Lithology: sand; gravel; clay or mud

fill and spoil (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

fill and spoil

Lithology: sand; silt; clay or mud

Beaumont Formation, areas predominantly clay (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers < 0.1 % of this area

Beaumont Formation, areas predominantly clay

Lithology: clay or mud; silt

Fleming Formation (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

Fleming Formation

Lithology: clay or mud; sandstone

Beaumont Formation, areas predominantly sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers < 0.1 % of this area

Beaumont Formation, areas predominantly sand

Lithology: sand; silt; clay or mud; gravel

Catahoula Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.1 % of this area

gray to white sandstones; loose quartz sand, tuffaceous sandstone, volcanic ash, and brown sandy clays; petrified wood locally. Overlain by 1-9 meters of loess.

Lithology: sandstone; sand; volcanic ash

Carizzo Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Carizzo Sand

Lithology: sandstone