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A total of 309 sediment samples from Sites U1325–U1329 were dried and crushed in an agate mortar. After adding a 1:5 ratio of corundum as an internal standard, the sample was homogenized with acetone and prepared as randomly oriented powder slides. X-ray diffraction (XRD) analyses were performed using a Philips PW 1710 instrument (CoKα) at the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven (Germany) with 40 kV accelerator voltage and 40 mA current. Scans were run from 3° to 100°2θ at a scanning speed of 0.02°/s. The interpretation was done using the MacDiff 4.2.2 program by Rainer Petschik ( The calcite content (in weight percent) was estimated using calibration curves for the calcite/corundum ratio. The MgCO3 content of calcite (in molar percent) was determined using the shift in the d(104) peak (Lumsden, 1979). The results for the mineral abundances are given in a qualitative way (modified after Vogt, 1997) as peak intensity (I) or integrated peak area (A) relative to I or A of the corundum standard (reflection at 2.085 Å [113]).