Samples were prepared using standard nannofossil smear slide techniques. Unprocessed sediment was smeared on a glass coverslip, dried, and then mounted on a glass slide using Norland optical adhesive mounting media. The nannofossil biostratigraphy presented here is based on examination of one to two samples per section using a Zeiss Axioscope under 625x-1560x magnification, employing phase-contrast, differential-interference contrast, and cross-polarized light. Core catcher samples were not examined for this study, but shipboard data from these samples were included to determine the depth of some biostratigraphic events. Semiquantitative abundance of each nannofossil species was recorded based on at least 300 nannofossils randomly encountered on the smear slide. Relative overall abundance of nannofossils in the samples is represented by the following abbreviations:
Preservation of the calcareous nannofossil assemblage was determined as follows:
Range charts presented herein as Tables T1, T2, T3, T4, and T5. were created with BugWin software (Bugware, Inc.) using these measurements. Calcareous nannofossil species considered in this paper are listed in the "Appendix," where they are arranged alphabetically by generic epithet. Additional notes clarifying species concepts are also included in the "Appendix". Key marker species were photographed for taxonomic clarity (Plate P1). Bibliographic references for these taxa can be found in Perch-Nielsen (1985) and Bown (1998).