Distribution of Foraminifera on the North Carolina Continental Shelf

Abstract

The quantitative distribution of one hundred and sixty-four species of foraminifera has been studied from eighty-six equal volume samples from the continental shelf of North Carolina. The area is strongly influenced by the Gulf Stream which follows the edge of the continental shelf north to Cape Hatteras from where it flows into the open ocean. A major faunal boundary exists at the latitude of Cape Hatteras, separating faunas which are characteristic for the central and northern Atlantic coasts of the U.S. from faunas which are similar to those from Florida and the Gulf of Mexico. It is possible to distinguish a syn-thanatotope of the central shelf with a lower boundary of about sixty meters and a syn-thanatotope of the shelf edge. The total number of both, benthonic and planktonic specimens, increases with increasing depth. A relict fauna is present on the outer portions of the central shelf and shelf edge which indicates a rise in sea level of about sixty meters since the last Pleistocene glaciation stage. Faunal diversity is higher south of Cape Hatteras which signifies the stabilizing influence of the Gulf Stream in this area.