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以冲绳海槽DGKS9603孔沉积物为研究对象,利用长链不饱和酮分子的不饱和指数U_(37)~K和沉积颗粒有机碳的δ~(13)C及浮游有孔虫(G.Sacculifer)的δ~(13)C重建冲绳海槽全新世表层海水温度和大气P_(CO_2)的演化历史;结合浮游有孔虫δ~(18)O,恢复了全新世海水表层盐度相对变化(ΔS).识别出了3次降温事件(E_1～E_3),其发生的时间分别为1.7～1.6,5.1～4.8和8.1～7.4 kaBP(cal).其中E_2和E_3事件具有全球可比性,其发生机制是在中全新世北半球日照强度增大、副热带高压增强,驱动西北太平洋环流加强,导致黑潮主流轴东移;E_1事件相当于1550～1850年间小冰期事件,在海槽区E_1事件可能与强盛冬季风导致的黑潮主流轴东移有关.
Taking the sediment of DGKS9603 in the Okinawa Trough as the research object, the unsaturated index of the long-chain unsaturated ketone U_ (37) ~ K and δ ~ (13) C of the sedimentary organic carbon and the distribution of planktonic foraminifera (G.Sacculifer ) Δ ~ (13) C reconstruction of the Okinawa Trough Holocene surface seawater temperature and atmospheric P_ (CO_2) evolution history; combined with planktonic foraminiferal δ ~ (18) O, to restore the seawater salinity relative changes in the Holocene ΔS). Three cooling events (E_1 ~ E_3) were identified and their occurrence time was 1.7 ~ 1.6, 5.1 ~ 4.8 and 8.1 ~ 7.4 kaBP, respectively, of which E_2 and E_3 events were globally comparable The mechanism is that in the mid-Holocene, the intensity of sunshine increases, the subtropical high increases and the northwest Pacific circulates, which leads to the eastward movement of the main stream of the Kuroshio. The E_1 event is equivalent to the Little Ice Age event from 1550 to 1850, and the E_1 event in the trough area may be related to Strong winter monsoon caused by the mainstream of the mainstream of the Kuroshio eastbound.