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

Geologic units in Beaufort county, South Carolina

Chenier plain and deltas of Suwannee & Chattahoochie Rivers (Holocene) at surface, covers 29 % of this area

Chenier plain and deltas of Suwannee & Chattahoochie Rivers

Lithology: unconsolidated deposit

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

Waccamaw Formation: Another Carolina costalized terrace of early-middle Pleistocene age. Deeply weathered.

Lithology: sand; limestone

Alluvial Valley Swamp (Quaternary) at surface, covers 2 % 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

Socastee Formation (Pleistocene) at surface, covers 18 % of this area

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

Lithology: sand; clay or mud

Tidal Marsh (Quaternary) at surface, covers 47 % of this area

Tidal Marsh: Peat and muck deposits along tidal margins of esturaries and back bays. Deposits range from a few feet to 60+ feet deep. Locally include silt and fine sand and clay as levees on tidal channels. At depth peaty material may be accumulated from fresh water plants. Peat at the surface dominated by spartina and other salt tolerant species.

Lithology: peat; silt; sand; clay or mud

Beach (Holocene) at surface, covers 2 % of this area

Beach: Holocene beach complex sediments. Sands and gravels of littoral zone, dune system, barrier system.

Lithology: sand; gravel