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对冲绳海槽南部ODP12 0 2站 16 5个沉积物样品进行了CaCO3 含量测定和 4 7个样品以浮游有孔虫为主的微体化石定量分析。应用CaCO3 含量变化与δ18O曲线的对应关系 ,初步将 12 0 2站岩心划分为MIS 1— 5期的沉积。根据浮游有孔虫中暖水、凉水、浅水和深水等生态组合丰度变化 ,推测冲绳海槽南部晚更新世末次间冰期以来 ,温跃层呈逐步加深和表层海水温度逐渐升高的趋势。MIS 5期以较浅温跃层和较低表层海水温度为特征 ,推测与研究区末次间冰期存在上升流有关。末次冰期 (MIS 4— 2期 )时 ,Pulleniatinaobliquiloculata在整个冲绳海槽中普遍以低丰度值出现 ,标志黑潮主流轴可能迁移出冲绳海槽
The sediment samples from 16 sediment samples from ODP12 0 2 station in the southern Okinawa Trough were measured for CaCO 3 content and 47 samples for quantitative analysis of fossils of planktonic foraminifera. According to the correspondence between the change of CaCO3 content and δ18O curve, the core of 12 0 2 station is initially divided into the MIS 1-5 deposition. According to the abundance of warm water, cold water, shallow water and deep water in planktonic foraminifera, it is inferred that the thermocline gradually deepens and the surface seawater temperature gradually increases since the late Pleistocene in the southern Okinawa Trough. MIS 5 is characterized by a relatively shallow thermocline and lower surface seawater temperature, suggesting that it is related to the upwelling of the last interglacial period in the study area. Pulleniatina obliquiloculata generally occurs at low abundance throughout the Okinawa Trough at the end of the Ice Age (MIS 4- 2), indicating that the mainstream Kuroshio axis may migrate out of the Okinawa Trough