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For diatom analyses, 189 samples from Sites U1325–U1329 were analyzed during the expedition, and 134 samples from Holes U1328B and U1328C were examined after the expedition. About 0.5 g of each wet sample was processed, and the methods of sample preparation, counting, and other procedures basically followed those of Akiba (1986) with a minor modification. Diatom abundance is expressed as an approximate number of diatom valves per slide (18 mm x 18 mm coverslip) calculated using the length of scanning lines needed to count 100 diatom valves. Resting spores of shallow-marine diatom genus Chaetoceros, which have generally been ignored in diatom analysis, were counted separately during the count of usual diatoms. In diatom biostratigraphic assignments, the Neogene diatom zonation and code numbers of the North Pacific Diatom Zone (NPD) by Akiba (1986) and Yanagisawa and Akiba (1998) were used. Ages for bioevents that define zones or characterize certain horizons are based on Yanagisawa and Akiba (1998). Specific occurrences of shipboard diatom analyses can be found in the site chapters, and only the occurrence of diatoms in Holes U1328B and U1328C is tabulated in this report.
For foraminifer analyses, 34 core catcher samples from Holes U1328B and U1328C were examined. The amount of material examined was 10 g for each sample, and the methods of preparation, counting, and other procedures followed those by Inoue (1989).