Neogene Benthic Foraminifers from DSDP Sites 360 and 362, Southeastern Atlantic

Abstract

Miocene to Quaternary benthic foraminifers have been examined from the South Atlantic Sites 360 and 362 (Figure 1). Site 360 is situated midway down the continental rise off Southwest Africa, at latitude 35°51'S, longitude 18°O5'E, in a water depth of 2977 meters. Site 362 is situated on the Abutment Plateau of the Frio Ridge segment of the Walvis Ridge, at latitude 19°45'S, longitude 10°32'E, in a water depth of 1325 meters. The portions examined are: Site 360, Cores 1-25 (lower Pliocene-lower Miocene); Site 362, Cores 1-38 (Pleistocene-lower Miocene). Most of the material examined consists of foraminifer-or diatom-rich nannofossil ooze and chalks. The benthic foraminifers are sparse, and in many instances only 1-2 specimens were found for each species present (Tables 1 and 2). The benthics appear as a very small portion of the total foraminifer fauna, in most cases less than 1% of the sample provided. The benthic faunas are dominated by long-ranging, moderate to deep-water species, not particularly suitable for biostratigraphic subdivision. Miliolids, mainly Quinqueloculina, and Biloculina are persistent throughout Sites 360 and 362. Arenaceous forms were found with six species present at Site 360, and nine at Site 362. From the range charts (Tables 1 and 2) it can be seen that the dominant and persistent forms are: