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

Geologic units in Caroline county, Virginia

[Additional scientific data in this geographic area]

Granite Gneiss (Proterozoic Y-Pennsylvanian) at surface, covers 0.4 % of this area

Granite gneiss.

Lithology: granitic gneiss

Newark Supergroup; Conglomerate, mixed clasts (Upper Triassic) at surface, covers 0.1 % of this area

Conglomerate, mixed clasts

Lithology: conglomerate

Pliocene Sand and Gravel (Tertiary) at surface, covers 30 % of this area

Pliocene Sand and Gravel - Sandy gravel, gravelly sand, poorly to well-sorted sands, and thin- to medium-beds of clay and silt, at altitudes from 170-320 ft. (top of unit).

Lithology: gravel; sand; clay or mud; silt

Chesapeake Group (Tertiary) at surface, covers 44 % of this area

Chesapeake Group - Fine- to coarse-grained sand, silt, clay; variably shelly and diatomaceous

Lithology: sand; silt; clay or mud

Alluvium (Quaternary) at surface, covers 3 % of this area

Alluvium - Poorly sorted organic material, clay, sand, and rounded pebbles and cobbles

Lithology: alluvium; clay or mud; sand

Potomac Formation (Cretaceous) at surface, covers 0.1 % of this area

Potomac Formation - Pebbly, poorly sorted quartzo-feldspathic sand interbedded with sandy clay and silt; minor organic-rich clay and silt

Lithology: sand; clay or mud; silt

Mylonite, Mylonite Gneiss, and Cataclastic Rocks (Proterozoic - Paleozoic ?) at surface, covers 0.1 % of this area

Mylonite, mylonite gneiss, and cataclastic rocks.

Lithology: mylonite; gneiss; cataclastite

State Farm Gneiss (Proterozoic Y) at surface, covers < 0.1 % of this area

State Farm Gneiss - Hornblende-biotite granite gneiss

Lithology: gneiss

Chuckatuck Formation (Quaternary) at surface, covers 0.3 % of this area

Chuckatuck Formation - Interbedded gravel, sand, silt, clay, and minor peat; at altitudes to 50-60 ft. (top of unit).

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

Lower Tertiary Deposits (Tertiary) at surface, covers 6 % of this area

Lower Tertiary Deposits - Glauconitic quartz sand and clay-silt, shelly in part, minor sandy limestone and limey sand; may include the following formations: Brightseat, Aquia, Marlboro, Nanjemay, and Piney Point (Pamunkey Group); and Old Church.

Lithology: sand; silt; limestone

Charles City Formation (Quaternary) at surface, covers 1 % of this area

Charles City Formation - Interbedded sand, silt, clay and minor gravel; at altitudes to 70-80 ft. (top of unit).

Lithology: sand; silt; clay or mud; gravel

Tabb Formation: Lynnhaven and Poquoson Members (Quaternary) at surface, covers 0.1 % of this area

Tabb Formation: Lynnhaven and Poquoson Members - Undifferentiated Qtl, Qts.

Lithology: sand; silt

Tabb Formation; Sedgefield Member (Quaternary) at surface, covers 0.3 % of this area

Tabb Formation; Sedgefield Member - Pebbly to bouldery, clayey sand and shelly sand, at altitudes to 30 ft. (top of unit).

Lithology: sand

Quartzofeldspathic Gneiss (Proterozoic Y-Pennsylvanian) at surface, covers 0.1 % of this area

Quartzofeldspathic gneiss

Lithology: felsic gneiss

Quaternary and Tertiary Deposits (Tertiary-Quaternary) at surface, covers 3 % of this area

Quaternary and Tertiary Deposits - Tabb through Windsor Formations and alluvial/tidal prism deposits.

Lithology: sand; gravel; silt; clay or mud; peat; alluvium

Newark Supergroup; Triassic Sandstone, Siltstone, and Shale (Upper Triassic) at surface, covers 0.2 % of this area

Interbedded sandstone, siltstone, and shale

Lithology: sandstone; siltstone; shale

Shirley Formation (Quaternary) at surface, covers 3 % of this area

Shirley Formation - Interbedded gravel, sand, silt, clay, and peat; at altitudes to 35-45 ft. (top of unit).

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

Bacons Castle Formation (Tertiary) at surface, covers 0.3 % of this area

Bacons Castle Formation - Gravel grading upward into sand and sandy clayey silt

Lithology: gravel; sand; silt; clay or mud

Miocene Sand and Gravel (Tertiary) at surface, covers 3 % of this area

Miocene Sand and Gravel - Sandy gravel, sand, silt, and clay.

Lithology: gravel; sand; silt; clay or mud

Porphyroblastic Garnet-Biotite Gneiss (Proterozoic Y) at surface, covers 4 % of this area

Porphyroblastic garnet-biotite gneiss.

Lithology: biotite gneiss

Tabb Formation (Quaternary) at surface, covers < 0.1 % of this area

Tabb Formation - Undifferentiated. Includes the Poquoson Member (Qtp), Lynnhaven Member ( Qtl) and Sedgefield Member (Qts).

Lithology: sand; silt; peat

Windsor Formation (Tertiary-Quaternary) at surface, covers 0.7 % of this area

Windsor Formation - Interbedded gravel, sand, silt, and clay; at altitudes to 85-95 ft. (top of unit).

Lithology: gravel; sand; silt; clay or mud