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“太阳号”17954站位于南海西部越南岸外夏季上升流区,沉积物记录了东亚夏季风的变化.本次研究在AMS14C测年基础上建立了严格的年龄框架,利用浮游有孔虫Globigerinoides ruber(white s.s.)的Mg/Ca-古海水温度计,对17954柱状样氧同位素三期(MIS3)表层海水古温度和盐度进行估算,并结合温跃层以及有孔虫初级生产力的变化探讨东亚夏季风在MIS3期的变化.研究表明,17954站G.ruber氧同位素与NGRIP冰芯以及葫芦洞石笋的氧同位素一样,存在显著的千年尺度的波动,显示了该海区表层环境变化与北半球高纬地区以及东亚夏季风变化的内在联系.17954站在MIS3期中记录了5个明显的温跃层变浅时期S1～S5,其中S1～S4时期均有表层海水温度和盐度降低、生产力增加的状况,表明在这些时期内有明显的上升流的存在,指示了较强的东亚夏季风,同时盐度的降低与夏季风带来较强的降水有关.
“Sun No. ” 17954 station is located in the rising summer flow area of summer in the west of South China Sea, the sediment records the change of East Asian summer monsoon.This study established a strict age framework based on the AMS14C dating, using planktonic foraminifera The ancient seawater temperature and salinity of the 17954 columnar sample oxygen isotope (MIS3) surface seawater were estimated by using the Mg / Ca-paleo seawater thermometer from Globigerinoides ruber (white ss), combining with the thermocline and the primary productivity of foraminifer East Asia summer monsoon change in MIS3 period.The results show that the G.ruber oxygen isotope at station 17954 has the same millennium-scale fluctuation as the NGRIP ice core and the oxygen isotope of the stalagmite of the gourd hole, indicating that the surface environmental change in this area is similar to that of the northern hemisphere Latitude and East Asia summer monsoon changes .In the MIS3 period, 17954 stations recorded five distinct periods S1 ~ S5 during the shallowening of the thermocline, in which the surface seawater temperature and salinity decreased from S1 to S4, and the productivity increased This indicates that there is a clear updraft in these periods, indicating strong East Asian summer monsoon, while the salinity reduction is related to the strong precipitation brought by the summer monsoon.