Coastal Plain - Primarily Subsurface Unit
The following description was published in GM13 Geologic Map of New Castle County, Delaware, Ramsey, K.W., 2005:
Reddish-brown to brown, medium to very coarse, poorly sorted sand to silty quartz sand containing scattered gravel beds. Less than 15 ft thick and underlies a relict terrace flat that has elevations between 170 ft and 180 ft and parallels the present Delaware River. More extensive to the north in Pennsylvania (Owens, 1999; Berg et al., 1980).
Berg, T.M., Edmunds, W.E., Geyer, A.R., and others, compilers, 1980, Geologic map of Pennsylvania: Pennsylvania Geological Survey, 4th ser., Map 1, scale 1:250,000, 3 sheets.
Owens, J.P., 1999, Cretaceous and Tertialy, <em>in</em> Shultz, C.H., editor, The Geology of Pennsylvania: Pennsylvania Geological Survey Special Publication No. 1, p. 219-223.