| Core IODP 315-C0002D retrieved from the South Japan Sea, has been used to reconstruct the sea surface paleotemperature (SST) recrord with the long-chain alkenones and alkyl alkenoates back to ca. 0.84 Ma, and analysed on planktonic foraminiferal faunas, to study the paleoceanography to study the variations of the paleoceanography condition and the paleo-Kuroshio Current in the Nankai Trough since the last 1 Ma. The core yielding a long time scale of the U37k'-derived temperature and planktonic foraminiferal assemble records in the Nankai Trough is good for studying the paleo-Kuroshio Current since the last 1 Ma, especially before the last glacial period.The U37k' -derived SST corresponds well with the glacial/interglacial cycles with some subordinate variations. Thirty-four species of planktonic foraminifera were identified in the core, and the faunas is dominant by Neogloboquadrina dutertrei, Turborotalia inflata and Neogloboquadrina pachyderma (dex).The temperate and sub-tropic groups are chiefly important to the planktonic foraminifera assemble,the tropic group is rather rare.The changes of the maxima species and ecological groups of the planktonic foraminiferal faunas respond well to the glacial/interglacial cycles. The U37k' -SST and the planktonic foraminifera assemble show that the marine condition in the study area was quite complex and inconstant. The upwelling and the Pacific Central Water Mass may be important to the area in addition to the Kuroshio Current.Strong impacts of the Kuroshio Current mainly concentrated in the interglacial periods, the study area was under the Kuroshio domain during the periods MIS17,MIS13,MIS7,MIS5-4 and MIS1. Nevertheless, the marine environment was controlled by the Pacific Central Water Mass ranther than the Kuroshio over the periods MIS19, and the Kuroshio domain may not been in the the study area during MIS15 and the interglacial periods berore MIS21.
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