(Table 1) Calcareous nannofossil distribution at ODP Site 180-1109 from the Solomon Sea, western Pacific

Oxygen isotope ratios in tests of the planktonic foraminifer Globigerinoides ruber allow us to assign the cores to oxygen isotope stages 7-1.Past sea-surface temperatures (SST) were estimated qualitatively using the composition of three Gephyrocapsa coccolith morphotypes; the high-, intermediate- and low-angel types that are classified based on the bridge angle of coccolith, can be used as proxies for warm, intermediate and cold temperature, respectively.

Abundance of the high-angel type coccoliths increased and decreased during the interglacial and glacial periods, respectively. This tendency is consistent with the expected change of the Western Pacific Warm Pool (WPWP) development. However, a large shift in the abundance of the high-angle type coccolith recorded during early stage 3 did not correspond to the oxygen isotope record.