Geologic units in Chesterfield county, South Carolina

Peedee Formation - Black Creek Group, undivided (Cretaceous) at surface, covers 62 % of this area

Peedee Formation - Black Creek Group, undivided

Cape Fear/Eutaw Formations (Cretaceous) at surface, covers 10 % of this area

Poorly sorted clayey sand and gravel deposited in delta-dominated fluvial- and restricted marine environments. Unit is characterized by an abundance of smoky quartz gravel, feldspar, monazite, and garnet typically concentrated in placer deposits. Generally non-marine from North Carolina to central Georgia but contains shallow-water delta-front deposits in western Georgia.

Persimmon Fork Formation (Cambrian to Neoproterozoic) at surface, covers 8 % of this area

Predominately metatuff

Alluvial Valley Swamp (Quaternary) at surface, covers 5 % of this area

Unconformable on all underlying units, fluvial sand and gravel at base, grading upwards into fine sands and silts, local peat. May be overrun with recent sediments from forest cutting and agriculture.

Cid Formation, Mudstone Member (Ordovician to Late Cambrian) at surface, covers 4 % of this area

Thin bedded tuffaceous metasiltstone

Richtex Formation (Ordovician to Middle Cambrian) at surface, covers 4 % of this area

Laminated metamudstone; contains Middle Cambrian or younger sponge spicules

Duplin Formation (Pliocene) at surface, covers 2 % of this area

Coastal terrace of Carolinas. Pliocene equivalent to Yorktown. Deeply weathered.

Brandywine Formation (Miocene) at surface, covers 1.0 % of this area

Upland gravel similar to Columbia group mapped in the uplands of southern Maryland southeast of DC. 10-40 ft thick. Extensive sand and gravel resources.

Chatham Group, undivided (Triassic) at surface, covers 1.0 % of this area

Conglomerate, sandstone and mudstone

Flat Swamp Formation (AKA Flat Swamp Member of Cid Formation) (Ordovician to Neoproterozoic) at surface, covers 0.9 % of this area

Crystal and lithic metatuff of rhyolite to rhyodacite composition

Granite - Pageland pluton (Carboniferous to Permian) at surface, covers 0.9 % of this area

Granite - Pageland pluton

Penholoway Formation (Pleistocene) at surface, covers 0.9 % of this area

Similar to Cape May, broad lateral extent underlying terraces in the Carolinas; swamps and ridges on terrace surface were originally barrier islands and back bays. Superimposed on these landforms are swarms of Carolina bays.

Socastee Formation (Pleistocene) at surface, covers 0.5 % of this area

Low coastal formation in Carolinas like Penholoway but younger and lower in altitude.

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

Sand, sandstone, and mudstone, gray to pale gray with an orange cast, mottled; clay balls and iron-cemented concretions common, beds laterally discontinuous, cross-bedding common.

Metamudstone and Meta-Argillite (Cambrian/Late Proterozoic) at surface, covers < 0.1 % of this area

Thin to thick bedded; bedding plane and axial-planar cleavage common; interbedded with metasandstone, metaconglomerate, and metavolcanic rock.

Granite (Carboniferous to Permian) at surface, covers < 0.1 % of this area

Granite