Millennial-scale paleoceanography in Okinawa Trough during Late Quaternaryperiod

Based on the analyses of foraminifer and accelerator mass spectrometer radi ocarbon dating in DGKS9603 core from mid-Okinawa Trough close to bottom, os cillation curve, which expressed the relation between the surface water tem perature and the depth, has been obtained by using foraminifer analysis and calculation of FP-12E transfer function. The whole core indicated seven co ld phases and eight warm phases. Obvious expression of low temperature even t during Middle and Late Holocene, YD,H1,H2,H3 and H4 events, as well as th e short cold phase during the middle last glacial period, implied that shor t shifts since 50 kaBP would have been global significance. Sedimentation r ate during cold phases is usually faster than that in warm stages, with the lowest rate in Holocene, which may be connected with rising sea level and principal axial of Kuroshio Current moving to west. Volcanic activities hig hly developed in Okinawa Trough during the Quaternary period, thus abundant volcanic glass and pumice were well preserved.