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Mineral Resources > Online Spatial Data > Geology > by state > North Carolina Geology

Geologic units in Brunswick county, North Carolina

Socastee Formation (Pleistocene) at surface, covers < 0.1 % of this area

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

Lithology: sand; clay or mud

Alluvial Valley Swamp (Quaternary) at surface, covers < 0.1 % of this area

Alluvial Valley Swamp: 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.

Lithology: sand; gravel; silt; peat

Surficial Deposits, Undivided (Quaternary) at surface, covers 4 % of this area

Surficial Deposits, Undivided - sand, clay, gravel, and peat deposited in marine, fluvial, eolian, and lacustrine environments. Quaternary deposits not shown at altitudes greater than approx. 205 feet above mean sea level (Suffolk Scarp, in part).

Lithology: lake or marine deposit (non-glacial); eolian; sand; clay or mud; gravel; peat

Peedee Formation (Cretaceous) at surface, covers 43 % of this area

Peedee Formation - sand, clayey sand, and clay, greenish gray to olive black, massive, glauconitic, locally fossiliferous and calcareous. Patches of sandy molluscan-mold limestone in upper part.

Lithology: sand; clay or mud; limestone

Waccamaw Formation (Tertiary) at surface, covers 50 % of this area

Waccamaw Formation - fossiliferous sand with silt and clay, bluish-gray to tan, loosely consolidated. Straddles Pleistocene-Pliocene boundary.

Lithology: sand; silt; clay or mud

Castle Hayne Formation; Comfort Member and New Hanover Member, undivided (Tertiary) at surface, covers 3 % of this area

Comfort Member and New Hanover Member, undivided - Comfort Member: bryozoan-echinoid skeletal limestone, locally dolomitized, solution cavities common. New Hanover Member: phosphate-pebble conglomerate, micritic, thin; restricted to basal part of Castle Hayne Formation in southeastern counties.

Lithology: limestone; dolostone (dolomite); conglomerate