The Zhejiang-Fujian mud area has been the sink of sediments since the formation of Holocene high sea level.Under the influence of the East Asian monsoon, the variation of ZhejiangFujian Coastal Current and Taiwan Warm Current is characterized by seasonality, the sediment transport pattern"trapped in summer and transported in winter"in the Yangtze River mouth plays a key role in the formation of the East China Sea inner-shelf mud area.The potential sources of the ZhejiangFujian mud area are the Yangtze River, Zhejiang-Fujian rivers and western Taiwan mountain rivers, and the Yangtze River materials are the main source.Through the analysis on clay minerals, rare earth elements, Sr Nd isotopes and environmental magnetism, the Yangtze River is dominated by illite, followed by kaolinite and chlorite, with less smectite.In the rivers of western Taiwan, illite and chlorite are the main clay materials, with no smectite.Pyrrhotite is a unique magnetic mineral of Taiwan river sediments, and can be used as an indicator of the source identification of sediments from rivers in mainland or Taiwan.The mud area is located in the East Asian monsoon region.Under the combined influence of the tropical processes in the low latitude and high latitude atmospheric circulation, the climate change is fluctuating.The changes in the East Asian Winter Monsoon (EAWM) reflected in sediment-sensitive grain size only record the climate changes since the formation of the muddy area, and cannot represent the entire Holocene.Influenced by the Taiwan Warm Current and Zhejiang-Fujian Coastal Current, the sensitive grain size needs to be further studied as an indicator of EAWM evolution.%浙闽泥质区是全新世高海平面以来沉积物的汇.受东亚季风影响,浙闽沿岸流和台湾暖流具有季节性变化,长江口"夏储冬输"的沉积物输运模式对东海内陆架泥质区的形成有关键作用.浙闽泥质区的潜在物源主要有长江、浙闽河流以及台湾西部山地河流,以长江物质为主.黏土矿物、稀土元素、Sr-Nd同位素、环境磁学等方法是物源研究的重要手段.长江物质以伊利石为主,蒙脱石含量较少,高岭石和绿泥石含量中等;而台湾物质以伊利石和绿泥石为主,没有蒙脱石.磁黄铁矿是台湾河流沉积物特有的磁性矿物,可作为大陆河流与台湾河流物源识别的指标.泥质区位于东亚季风区,受低纬热带过程和高纬大气环流的影响,气候变化具有波动性.沉积物敏感粒级反演的东亚冬季风(EAWM)只记录了泥质区形成以来的气候变化,不能代表整个全新世.受台湾暖流和浙闽沿岸流的双重影响,敏感粒级作为EAWM演化的指标需进一步深入研究.
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