Southeastern Section–56th Annual Meeting (29–30 March 2007)

Paper No. 6
Presentation Time: 3:00 PM


PARHAM, Peter R.1, RIGGS, Stanley R.2 and MALLINSON, David J.1, (1)Department of Geological Sciences, East Carolina University, Greenville, NC 27858, (2)Department of Geological Sciences, East Carolina Univ, Greenville, NC 27858,

The north-south trending Suffolk Shoreline (SS) is considered to be the product of possibly several sea-level highstands that occurred during MIS 5. LiDAR imagery reveals that the paleo-feature is split into two roughly parallel sand ridges in some areas. Corresponding highstand facies should occur in the subsurface to the east as marine deposits and extend up drainages to the west as estuarine deposits. This study seeks to characterize SS deposits and correlate them with contemporary facies in the subsurface using ground penetrating radar and a combination of optically stimulated luminesence, U-series, and amino acid racemization age dating techniques. Eighteen Geoprobe cores, ranging in depth from 7 m to 15 m, have been obtained along three 10 km to 40 km transects across the SS on both the Pamlico/Neuse and Albemarle/Pamlico Peninsulas, northeastern North Carolina. Most cores terminate in the Pliocene Yorktown Formation. Three similar transects will be conducted between Albemarle Sound and the James River, southeastern Virginia. Ground penetrating radar surveys will facilitate stratigraphic correlation between cores. Preliminary lithologic analysis indicates that depositional sequences in the study area are bounded by soil profiles and typically grade up section from wood and plant detritus-rich, muddy swamp forest deposits to laminated mud and sand estuarine deposits to mollusk shell-rich, marine muddy sand. Where preserved along the SS, paleo-shoreline deposits typically consist of up to 5 m of humate-rich sand to muddy sand overlying laminated estuarine deposits. Mollusk shell-rich sediments are considered to represent highstand deposition and occur above the Yorktown Formation both west and east of the SS. The inter-relationship between these shell-rich sediments and their chronologic relationship with SS deposits is yet to be established.