METHODS

For this preliminary study a 20-cm3 sample was collected from every core section, plus (larger) core catcher samples, with an additional subsequent 20-cm3 sample from sections where foraminifers were identified by the sedimentological description. The wet samples were processed aboard ship.The samples were soaked in distilled water and agitated for an hour to assist in disaggregation then were wet-sieved at 63 µm. The washed residue was dried under a heat lamp, and the temperature was monitored so as not to exceed 50°C. Samples were dry sieved at 150 µm, and all planktonic foraminifers were picked from the sample. In foraminifer-rich samples, a maximum of 50 foraminifers was picked. All samples measured were the quadrate form of N. pachyderma (s) (the "encrusted" form of Kohfeld et al., 1996).

For isotopic analysis (at the Godwin Laboratory, University Cambridge, United Kingdom), the foraminifer samples were picked into glass vials, crushed, and soaked in a 3% solution of hydrogen peroxide for 30 min. Acetone was added, the sample was ultrasonicated for 30 s, and the liquid was carefully decanted using a tissue. The samples were then dried in an oven at 50°C overnight. The smaller samples ("M" in the tables) were transferred to larger glass vials that were sealed with a septa and cap and analyzed using a Micromass Multicarb sample preparation system attached to a PRISM mass spectrometer. The larger samples ("S") were transferred to smaller glass containers and analyzed using a Micromass Autocarb common acid bath system attached to a SIRA mass spectrometer. A series of calibration and check carbonates were analyzed with every batch of samples. Results are reported with reference to the international standard Vienna Peedee belemnite (VPDB), and the precision is better than ±0.06 ppm for 13C and ±0.08 ppm for 18O.

Measurements from both sites are listed in Tables T1 and T2 and displayed against depth in Figure F1. Ages were attributed to samples assuming uniform sedimentation rates between shipboard-identified magnetic reversals.

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