Onshore Calcareous Nannofossil Biostratigraphy of Atlantic Margin Cretaceous and Paleogene: ABSTRACT

Abstract

Calcareous nannofossils in onshore marine samples from 19 outcrops, 9 cores, and 23 drilled wells permit correlation of surface and subsurface units from New Jersey (NJ) to South Carolina (SC) with the exception of the Delaware-Virginia (DEL-VA) area where the Cretaceous is nonmarine. Cenomanian (nannofossil Cretaceous zone nc II) sediments are present in North Carolina (NC) and SC but not northward. Turonian (~nc 12-14) sediments are present in NJ, NC, and SC but the Coniacian-Santonian (~nc 15-17) interval is well represented only in NC, being either very thin, absent, or nonfossiliferous on the north and south. A thick laterally persistent Campanian (~nc 18-20) sequence occurs in SC, NC, and NJ and is overlain by a thinner Maestrichtian (~nc 20-23) layer. Upper Maestri htian is present in NJ but absent in NC and SC. The Cretaceous-Tertiary boundary is paleontologically unconformable along the Atlantic margin with lower to upper Paleocene resting on lower to upper Maestrichtian. The Paleogene is thinner than the Cretaceous owing to decreased thermal subsidence of the aging Atlantic margin coupled with general marine regression. Lower (~NP 1-2) and Upper (~NP 5-9) Paleocene strata are laterally persistent from NJ to NC (including DEL-VA) but are not yet studied in SC. Lower to middle Eocene sediments (NP 10-15) are persistent throughout the Atlantic Coastal Plain but middle to upper Eocene units (NP 16-20) are absent north of VA. Lower Oligocene strata (NP 21-22) are present only in NC whereas upper Oligocene (NP 23-24) sediments extend from NJ to VA but not southward. Overall, a sequence of transg essive-regressive facies is recognizable but is strongly overprinted locally by structural complications. End_of_Article - Last_Page 1673------------