Geology of the Black Mingo Group (Paleocene) in the Kingstree and St. Stephen Areas of South Carolina

Abstract

PALEOCENE VERTEBRATE REMAINS from the areas of Kingstree and St. Stephen, South Carolina, come from the Rhems and Williamsburg formations of the Black Mingo Group. Sedimentary textures and fossils indicate that both units accumulated in shallow, nearshore marine, lagoonal, and deltaic depositional environments. Calcareous nannofossils and dinoflagellates indicate that the vertebrate-bearing portions of the Williamsburg Formation near St. Stephen belong within calcareous nannoplankton Zones NP 3-5 (Lower Bridge Member) and within calcareous nannoplankton zones NP 8-9 (Chicora Member). Paleocene vertibrate remains from Kingstree probably all come from near the base of the Rhems Formation. Introduction The towns of Kingstree and St. Stephen, located in the east-central part of the South Carolina Coastal Plain (Figure 1), lie within the outcrop belt of the richly fossiliferous Black Mingo Group. This group is composed of the Rhems Formation (lower Paleocene), the Williamsburg Formation (lower? and upper Paleocene), and the Fishburne Formation (lower Eocene) (Gohn et al., 1983). During the last two decades, numerous vertebrate fossils have been recovered from the vicinity of both towns. Remains that are of Paleocene age are the focus of this volume. Kingstree area In and near Kingstree, especially in Clapp Creek within the town limits (Erickson, 1998, this volume), vertebrate remains have been recovered largely by digging in small pits or ditches. These excavations have yielded a wide variety of fossils ranging from Late Cretaceous to Pliocene and/or Pleistocene in age. The stratigraphy in the immediate vicinity of these pits is poorly known. However, the abundant presence of phosphate pebbles and the generally worn and abraded appearance of most of the fossils strongly indicate that most of these