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对取自热带西太平洋暖池核心区的WP7岩心进行了底栖有孔虫和钙质超微化石研究。在利用氧同位素曲线对比和AMS14C测年数据进行地层划分的基础上,依据底栖有孔虫和钙质超微化石指标,分析了距今近250ka以来区域生产力和上层海水结构的演变特征,探讨了其控制因素和所指示的古海洋学意义。计算结果显示WP7岩心所在的暖池核心区约在距今250ka以来初级生产力在冰期(MIS6期、4期和2期)高,在间冰期(MIS7期、5期、3期和1期)低,表明该区古生产力在长的轨道时间尺度上受北半球高纬度冰量变动的影响。钙质超微化石下透光带属种Flori-sphaera profunda百分含量指示的温跃层深度变化表明冰期温跃层浅、间冰期温跃层加深,这说明类ENSO式变化导致的冰期—间冰期温跃层深度波动可能是MIS7期以来暖池核心区古生产力在冰期高而在间冰期显著降低的直接控制因素。
Benthic foraminifera and calcareous microfossils were studied on WP7 cores taken from the core of the tropical western Pacific warm pool. Based on the stratigraphic division of oxygen isotope curves and AMS14C dating data, the characteristics of regional productivity and the evolution of the upper seawater structure since the last 250 ka are analyzed based on the benthic foraminifera and calcareous nanofossil indicators Its controlling factors and the paleo-oceanographic significance indicated. The calculated results show that the core area of the warm pool where WP7 core is located is about high in the glacial (MIS6, 4 and 2) since about 250 ka, and low in interglacials (MIS7, 5, 3 and 1) , Indicating that the ancient productivity of the area is affected by the change of ice volume in the high latitudes of the northern hemisphere over a long orbital time scale. The changes of the thermocline depth indicated by Flori-sphaera profunda percentage in calcareous microfossils indicate that the glacial thermocline is shallow and the interglacial thermocline deepens, indicating that the ENSO-like changes in glacial-intergranular The temperature fluctuation of the glacial thermocline may be the direct control factor for the paleoclimate productivity in the core area of the Warm Pool during MIS7 since it was high in glacial period and significantly decreased in inter-glacial period.