PALEOECOLOGY OF FORAMINIFERAL ASSEMBLAGES FROM PLIO-PLEISTOCENE LOCALITIES IN NORTH CAROLINA
Six bulk samples were collected from five localities in NC and processed for microfossils. Samples representing the Duplin Formation (Pliocene) were obtained from Tar Heel and along the Lumber River near Lumberton. The other four samples belong to the lower Waccamaw Formation (Pleistocene) and were collected at Acme, Holloman Pit in Whiteville, and a lower and upper bed at Register Quarry near Old Dock. Over 300 foraminifers were picked from each sample and identification of all foraminifers to genus level is near complete.
Foraminiferal suborders observed include Rotaliina, Miliolina, Textulariina, Lagenina, Globigerinina, and Spirillinina. Rotaliids dominate samples from Tar Heel (98%), Lumber River (91%), Acme (74%), and the lower (84%) and upper (92%) beds at Register Quarry. Miliolids (52%) are slightly more abundant than rotaliids (46%) at Holloman Pit. The Tar Heel sample is composed almost entirely of the rotaliid Amphistegina; Lumber River material is dominated by the rotaliid Cibicides. All Waccamaw samples are characterized primarily by Amphistegina, but the miliolid Quinqueloculina is also abundant at Acme and Holloman Pit.
These foraminiferal assemblages indicate warm, shallow, normal marine, inner- to middle-shelf environments, in part based on the literature of microfossils from these units in the Carolinas (e.g., Howard, 1974). Previous REU work on microfossils from these and other Plio-Pleistocene localities in NC and SC yielded similar results (e.g., Parnell et al., 2009; Borges-Farfan et al., 2010; Thornberg et al., 2011). Identification of foraminifers is ongoing, and forthcoming paleoecological data from both foraminifers and ostracods will be combined to refine paleoenvironmental reconstructions.