晚第四纪来东亚季风和ENSO交织影响下的古海洋学响应：以黑潮源区为例

The Kuroshio source region is a key area for researching evolutions of the low-latitude processes (East Asian monsoon and ENSO), and thus can provide good materials for discussing the tropical forcing mechanism of global climate cycle. Nevertheless, the comprehensive research on their long-term changes in the study area remains unsolved. Based on two high-quality long sediment cores including MD06-3047 and MD06-3052 collected during a Chinese-French joint cruise, together with some modern-formed surface sediments, in the study area, the terrigenous sediment provenance as well as the alteration degree will be (semi-quantitatively) quantitatively constrained by clay minerals as well as geochemical elements and Sr-Nd isotopes of terrigenous detrital fraction in the context of accurate chronology got from the previous work of the National Basic Research Program of China (No.2007CB815903). And then these changes can be discussed in the context of East Asian winter monsoon and East Asian summer monsoon evolutions. Besides, we will use foraminifer and calcareous nannofossil community, carbon isotope of typical foraminifer species, and organic carbon content to (semi-quantitatively) quantitatively calculate the depth of thermocline (nutricline), ENSO cycle, and primary productivity level. And then we can constrain evolutions of the low-latitude processes, the relationship between each composition, and their paleoceanography effects (e.g., sediment source-to-sink process, upper water structure, and nutrient level) in the study area over orbital-millennial time scales.

黑潮源区是研究低纬过程（东亚季风和ENSO）演化的理想靶区，进而可为全球气候变化的热带驱动机制探索提供良好素材，但其长期、综合性演化记录追溯迄今未见。本项目利用黑潮源区2根中-法合作高质量长岩芯及现代沉积物样品，基于前期973项目中建立的准确年龄框架，通过粘土矿物及陆源碎屑态元素和锶、钕同位素来（半）定量识别大陆物质贡献及其风化程度进而反演东亚冬、夏季风强度，根据有孔虫和钙质超微化石群落结构及其特征属种碳同位素和有机质含量来（半）定量估算温（营养）跃层深度、ENSO过程及初级生产力水平，进而查明研究区晚第四纪来轨道-千年时间尺度上低纬过程的演化历史、各组分间联系及其古海洋学响应过程（如沉积物源-汇过程、上层水体结构及营养水平）。

黑潮源区是研究低纬过程（东亚季风和厄尔尼诺-南方涛动）演化的理想靶区，进而可为全球气候变化的热带驱动机制探索提供良好素材，但其长期、综合性演化记录追溯迄今未见。本项目利用黑潮源区4根中-法合作高质量长岩芯及现代沉积物捕获器样品，基于前期973项目中建立的准确年龄框架，通过粘土矿物及陆源碎屑态元素和Sr-Nd同位素来定量识别了不同来源陆源物质贡献及其风化程度进而反演了东亚冬、夏季风强度，根据有孔虫和钙质超微化石群落结构及其特征属种碳同位素和有机质含量来定量估算了温（营养）跃层深度、厄尔尼诺-南方涛动过程及初级生产力水平，进而查明了研究区第四纪来构造-轨道-千年-百年时间尺度上低纬过程的演化历史、各组分间联系及其古海洋学响应过程（如沉积物源-汇过程、上层水体结构及营养水平），并探讨了冰期低海平面时期吕宋岛周边出露的松散陆架沉积物的硅酸盐风化作用及其全球碳循环效应。

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