奄美三角盆地风尘记录的研究，对于揭示东亚大陆季风和西风环流，以及干旱气候的形成和演化具有重要意义。本项目拟使用IODP 351航次采集的高质量岩芯U1438B孔沉积物，通过多种物源示踪指标（如：粒度、粘土矿物、石英、Sr和Nd同位素等）的综合分析，以及和可能源区的对比研究，识别奄美三角盆地中新世以来风尘组分和判别风尘源区，提取具有西风和季风指示意义的指标。通过与东亚大陆和北太平洋风尘的对比研究，揭示中新世以来大气环流的形成和演化；通过U1438B孔碎屑组分粒度分布函数和Sr同位素端元混合模型研究，获得奄美三角盆地中新世以来可供区域和全球对比的可靠风尘通量。依据风尘通量的变化规律与陆地风尘和北太平洋风尘通量开展对比研究，揭示东亚大陆中新世以来的干旱历史。通过构造尺度风尘古气候记录的变化，与中新世以来全球变冷，两极冰盖发育，青藏高原隆升等重大地质事件的对比研究，探讨东亚大陆古气候演化机制。

The study on eolian dust in the sediment of Amami Sankaku Basin is useful to reconstruct the formation and evolution of atmospheric circulation system (East Asian Monsoon and prevailing westerly) and aridity history of East Asia continent. This proposal is designed to study the eolian dust record in an Advanced Piston Core U1438B recovered from Amami Sankaku Basin during IODP expedition 351. Multi-proxies (e.g. grain size, clay minerals, quartz, Sr and Nd isotope compositions) in the detrital sediment will be used to identify eolian dust signature and to trace dust source area since Miocene. The indicators of paleoclimate for Eat Asia will be obtained based on the study of multi-proxies. By comparing the dust record in APC core U1438B with the eolian record in East Asia continent and central North Pacific, we will try to clarify the onset and evolution East Asia Monsoon and westerly since Miocene. Two different methods (Weibull function of grain size distribution and two end-member mixing model of Sr isotope) will be used to separate eolian dust from volcanic materials quantatively, and to obtain the reliable dust flux which can be compared with local and global dust flux. By comparing the variation of dust flux in Amami Sankaku Basin with that in East Asia continent and central north Pacific, we try to disclose the aridity history of East Asia continent. According to the coupling on tectonic time-scale between the dust records and the significant tectonic events (e.g. global cooling, the formation of ice sheet, the uplift of Tibetan Plateau) since Miocene, the constrained mechanism of paleoclimate of East Asia will be studied.