Tabb Formation; Sedgefield Member

Sedgefield Member (Johnson, 1976). Pebbly to bouldery, clayey sand and fine to medium, shelly sand that grades upward into sandy and clayey silt; locally channel fill at base of unit includes as much as 50 feet of fine to coarse, cross-bedded sand and clayey silt and peat containing in-situ tree stumps. Sandy bay facies commonly contains Crassostrea biostromes, Mercenaria, Anadara, Polynices, Ensis, and other mollusks. Specimens of the coral Astrangia have yielded estimated uranium-series ages averaging 71,000 ± 7,000 yrs B.P. (Mixon and others, 1982). Unit constitutes surficial deposit to river and coast-parallel plains (altitude 20-30 feet) bounded on landward side by Suffolk and Harpersville scarps. Thickness is 0 to 50 feet.
State Virginia
Name Tabb Formation; Sedgefield Member
Geologic age Quaternary
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand
Comments Coastal Plain
References

Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000.

Virginia Division of Mineral Resources, 2003, Digital Representation of the 1993 Geologic Map of Virginia, Publication 174, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, scale 1:500,000.

NGMDB product
Counties Caroline - Charles City - Chesterfield - Essex - Gloucester - Hanover - Henrico - Isle of Wight - James City - King and Queen - King George - King William - Lancaster - Mathews - Middlesex - New Kent - Northumberland - Prince George - Richmond - Southampton - Sussex - Westmoreland - York - Chesapeake - Franklin - Hampton - Newport News - Norfolk - Portsmouth - Richmond - Suffolk - Virginia Beach